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+*** START OF THE PROJECT GUTENBERG EBOOK 42968 ***
+
+    Transcriber's Note:
+
+    Every effort has been made to replicate this text as faithfully as
+    possible, including inconsistencies in hyphenation. It seems that
+    the italic typeface used in this book did not have an ae ligature.
+    Names of genera and higher taxonomic groups are not capitalized in
+    the printed book: they have bee left unchanged. Some changes have
+    been made. They are listed at the end of the text.
+
+    Italic text has been marked with _underscores_.
+    OE ligatures have been expanded.
+
+
+
+
+THE RIDDLE OF THE UNIVERSE
+
+
+[Illustration: ERNST HAECKEL]
+
+
+
+
+                               THE RIDDLE
+                            OF THE UNIVERSE
+
+                            _AT THE CLOSE OF
+                        THE NINETEENTH CENTURY_
+
+                                   BY
+
+                             ERNST HAECKEL
+
+            (Ph.D., M.D., LL.D., Sc.D., and Professor at the
+                          University of Jena)
+
+                  AUTHOR OF "THE HISTORY OF CREATION"
+                      "THE EVOLUTION OF MAN" ETC.
+
+                             TRANSLATED BY
+
+                             JOSEPH McCABE
+
+                             [Illustration]
+
+                      HARPER & BROTHERS PUBLISHERS
+                          NEW YORK AND LONDON
+                                  1905
+
+
+
+
+                 Copyright, 1900, by HARPER & BROTHERS.
+
+                         _All rights reserved._
+
+
+
+
+CONTENTS
+
+
+                                       PAGE
+
+    AUTHOR'S PREFACE                      v
+
+    TRANSLATOR'S PREFACE                 xi
+
+    CHAPTER I
+    THE NATURE OF THE PROBLEM             1
+
+    CHAPTER II
+    OUR BODILY FRAME                     22
+
+    CHAPTER III
+    OUR LIFE                             39
+
+    CHAPTER IV
+    OUR EMBRYONIC DEVELOPMENT            53
+
+    CHAPTER V
+    THE HISTORY OF OUR SPECIES           71
+
+    CHAPTER VI
+    THE NATURE OF THE SOUL               88
+
+    CHAPTER VII
+    PSYCHIC GRADATIONS                  108
+
+    CHAPTER VIII
+    THE EMBRYOLOGY OF THE SOUL          132
+
+    CHAPTER IX
+    THE PHYLOGENY OF THE SOUL           148
+
+    CHAPTER X
+    CONSCIOUSNESS                       170
+
+    CHAPTER XI
+    THE IMMORTALITY OF THE SOUL         188
+
+    CHAPTER XII
+    THE LAW OF SUBSTANCE                211
+
+    CHAPTER XIII
+    THE EVOLUTION OF THE WORLD          233
+
+    CHAPTER XIV
+    THE UNITY OF NATURE                 254
+
+    CHAPTER XV
+    GOD AND THE WORLD                   275
+
+    CHAPTER XVI
+    KNOWLEDGE AND BELIEF                292
+
+    CHAPTER XVII
+    SCIENCE AND CHRISTIANITY            308
+
+    CHAPTER XVIII
+    OUR MONISTIC RELIGION               331
+
+    CHAPTER XIX
+    OUR MONISTIC ETHICS                 347
+
+    CHAPTER XX
+    SOLUTION OF THE WORLD-PROBLEMS      365
+
+    CONCLUSION                          380
+
+    INDEX                               385
+
+
+
+
+AUTHOR'S PREFACE
+
+
+The present study of the monistic philosophy is intended for thoughtful
+readers of every condition who are united in an honest search for the
+truth. An intensification of this effort of man to attain a knowledge
+of the truth is one of the most salient features of the nineteenth
+century. That is easily explained, in the first place, by the immense
+progress of science, especially in its most important branch, the
+history of humanity; it is due, in the second place, to the open
+contradiction that has developed during the century between science
+and the traditional "Revelation"; and, finally, it arises from the
+inevitable extension and deepening of the rational demand for an
+elucidation of the innumerable facts that have been recently brought to
+light, and for a fuller knowledge of their causes.
+
+Unfortunately, this vast progress of empirical knowledge in our
+"Century of Science" has not been accompanied by a corresponding
+advancement of its theoretical interpretation--that higher knowledge of
+the causal nexus of individual phenomena which we call philosophy. We
+find, on the contrary, that the abstract and almost wholly metaphysical
+science which has been taught in our universities for the last hundred
+years under the name of "philosophy" is far from assimilating our
+hard-earned treasures of experimental research. On the other hand, we
+have to admit, with equal regret, that most of the representatives
+of what is called "exact science" are content with the special care
+of their own narrow branches of observation and experiment, and
+deem superfluous the deeper study of the universal connection of
+the phenomena they observe--that is, philosophy. While these pure
+empiricists "do not see the wood for the trees," the metaphysicians, on
+the other hand, are satisfied with the mere picture of the wood, and
+trouble not about its individual trees. The idea of a "philosophy of
+nature," to which both those methods of research, the empirical and the
+speculative, naturally converge, is even yet contemptuously rejected by
+large numbers of representatives of both tendencies.
+
+This unnatural and fatal opposition between science and philosophy,
+between the results of experience and of thought, is undoubtedly
+becoming more and more onerous and painful to thoughtful people. That
+is easily proved by the increasing spread of the immense popular
+literature of "natural philosophy" which has sprung up in the course
+of the last half-century. It is seen, too, in the welcome fact that,
+in spite of the mutual aversion of the scientific observer and the
+speculative philosopher, nevertheless eminent thinkers from both
+camps league themselves in a united effort to attain the solution
+of that highest object of inquiry which we briefly denominate the
+"world-riddles." The studies of these "world-riddles" which I offer in
+the present work cannot reasonably claim to give a perfect solution of
+them; they merely offer to a wide circle of readers a critical inquiry
+into the problem, and seek to answer the question as to how nearly we
+have approached that solution at the present day. What stage in the
+attainment of truth have we actually arrived at in this closing year of
+the nineteenth century? What progress have we really made during its
+course towards that immeasurably distant goal?
+
+The answer which I give to these great questions must, naturally, be
+merely subjective and only partly correct; for my knowledge of nature
+and my ability to interpret its objective reality are limited, as are
+those of every man. The one point that I can claim for it, and which,
+indeed, I must ask of my strongest opponents, is that my Monistic
+Philosophy is sincere from beginning to end--it is the complete
+expression of the conviction that has come to me, after many years of
+ardent research into Nature and unceasing reflection, as to the true
+basis of its phenomena. For fully half a century has my mind's work
+proceeded, and I now, in my sixty-sixth year, may venture to claim
+that it is mature; I am fully convinced that this "ripe fruit" of the
+tree of knowledge will receive no important addition and suffer no
+substantial modification during the brief spell of life that remains to
+me.
+
+I presented all the essential and distinctive elements of my monistic
+and genetic philosophy thirty-three years ago, in my _General
+Morphology of Organisms_, a large and laborious work, which has had but
+a limited circulation. It was the first attempt to apply in detail the
+newly established theory of evolution to the whole science of organic
+forms. In order to secure the acceptance of at least one part of the
+new thought which it contained, and to kindle a wider interest in the
+greatest advancement of knowledge that our century has witnessed, I
+published my _Natural History of Creation_ two years afterwards.
+As this less complicated work, in spite of its great defects, ran
+into nine large editions and twelve different translations, it has
+contributed not a little to the spread of monistic views. The same
+may be said of the less known _Anthropogeny_[1] (1874), in which I
+set myself the difficult task of rendering the most important facts
+of the theory of man's descent accessible and intelligible to the
+general reader; the fourth, enlarged, edition of that work appeared in
+1891. In the paper which I read at the fourth International Congress
+of Zoology at Cambridge, in 1898, on "Our Present Knowledge of the
+Descent of Man"[2] (a seventh edition of which appeared in 1899), I
+treated certain significant and particularly valuable advances which
+this important branch of anthropology has recently made. Other isolated
+questions of our modern natural philosophy, which are peculiarly
+interesting, have been dealt with in my _Collected Popular Lectures on
+the Subject of Evolution_ (1878). Finally, I have briefly presented
+the broad principles of my monistic philosophy and its relation to the
+dominant faith in my _Confession of Faith of a Man of Science: Monism
+as a Connecting Link between Religion and Science_[3] (1892, eighth
+edition, 1899).
+
+The present work on _The Riddle of the Universe_ is the continuation,
+confirmation, and integration of the views which I have urged for a
+generation in the aforesaid volumes. It marks the close of my studies
+on the monistic conception of the universe. The earlier plan, which
+I projected many years ago, of constructing a complete "System of
+Monistic Philosophy" on the basis of evolution will never be carried
+into effect now. My strength is no longer equal to the task, and many
+warnings of approaching age urge me to desist. Indeed, I am wholly a
+child of the nineteenth century, and with its close I draw the line
+under my life's work.
+
+The vast extension of human knowledge which has taken place during
+the present century, owing to a happy division of labor, makes
+it impossible to-day to range over all its branches with equal
+thoroughness, and to show their essential unity and connection.
+Even a genius of the highest type, having an equal command of every
+branch of science, and largely endowed with the artistic faculty of
+comprehensive presentation, would be incapable of setting forth a
+complete view of the cosmos in the space of a moderate volume. My own
+command of the various branches of science is uneven and defective,
+so that I can attempt no more than to sketch the general plan of such
+a world-picture, and point out the pervading unity of its parts,
+however imperfect be the execution. Thus it is that this work on the
+world-enigma has something of the character of a sketch-book, in which
+studies of unequal value are associated. As the material of the book
+was partly written many years ago, and partly produced for the first
+time during the last few years, the composition is, unfortunately,
+uneven at times; repetitions, too, have proved unavoidable. I trust
+those defects will be overlooked.
+
+In taking leave of my readers, I venture the hope that, through my
+sincere and conscientious work--in spite of its faults, of which I am
+not unconscious--I have contributed a little towards the solution
+of the great enigma. Amid the clash of theories, I trust that I have
+indicated to many a reader who is absorbed in the zealous pursuit of
+purely rational knowledge that path which, it is my firm conviction,
+alone leads to the truth--the path of empirical investigation and of
+the Monistic Philosophy which is based upon it.
+
+                                                          ERNST HAECKEL.
+
+JENA, GERMANY.
+
+
+
+
+PREFACE
+
+
+The hour is close upon us when we shall commence our retrospect of one
+of the most wonderful sections of time that was ever measured by the
+sweep of the earth. Already the expert is at work, dissecting out and
+studying his particular phase of that vast world of thought and action
+we call the nineteenth century. Art, literature, commerce, industry,
+politics, ethics--all have their high interpreters among us; but in
+the chance of life it has fallen out that there is none to read aright
+for us, in historic retrospect, what after ages will probably regard
+as the most salient feature of the nineteenth century--the conflict
+of theology with philosophy and science. The pens of our Huxleys,
+and Tyndalls, and Darwins lie where they fell; there is none left in
+strength among us to sum up the issues of that struggle with knowledge
+and sympathy.
+
+In these circumstances it has been thought fitting that we should
+introduce to English readers the latest work of Professor Haeckel.
+Germany, as the reader will quickly perceive, is witnessing the same
+strange reaction of thought that we see about us here in England,
+yet _Die Welträthsel_ found an immediate and very extensive circle
+of readers. One of the most prominent zoologists of the century,
+Professor Haeckel, has a unique claim to pronounce with authority, from
+the scientific side, on what is known as "the conflict of science and
+religion." In the contradictory estimates that are urged on us--for
+the modern ecclesiastic is as emphatic in his assurance that the
+conflict has ended favorably to theology as the rationalist is with his
+counter-assertion--the last words of one of the leading combatants of
+the second half of the century, still, happily, in full vigor of mind,
+will be heard with respect and close attention.
+
+A glance at the index of the work suffices to indicate its comprehensive
+character. The judgment of the distinguished scientist cannot fail
+to have weight on all the topics included; yet the reader will soon
+discover a vein of exceptionally interesting thought in the chapters
+on evolution. The evolution of the human body is no longer a matter
+of serious dispute. It has passed the first two tribunals--those of
+theology and of an _à priori_ philosophy--and is only challenged at the
+third and last--that of empirical proof--by the decorative heads of
+scientific bodies and a few isolated thinkers.
+
+    "_Apparent rari nantes in gurgite vasto._"
+
+But the question of the evolution of the human mind, or soul, has been
+successfully divorced from that of the body. Roman Catholic advanced
+theologians, whose precise terminology demanded a clear position, admit
+the latter and deny the former categorically. Other theologians, and
+many philosophers, have still a vague notion that the evidence for
+the one does not impair their sentimental objection to the other. Dr.
+Haeckel's work summarizes the evidence for the evolution of mind in
+a masterly and profoundly interesting fashion. It seems impossible to
+follow his broad survey of the psychic world, from protist to man,
+without bearing away a conviction of the natural origin of every power
+and content of the human soul.
+
+                                                             TRANSLATOR.
+
+_October, 1900._
+
+
+
+
+THE RIDDLE OF THE UNIVERSE
+
+
+
+
+CHAPTER I
+
+THE NATURE OF THE PROBLEM
+
+    The Condition of Civilization and of Thought at the Close of
+    the Nineteenth Century--Progress of Our Knowledge of Nature,
+    of the Organic and Inorganic Sciences--The Law of Substance
+    and the Law of Evolution--Progress of Technical Science and
+    of Applied Chemistry--Stagnancy in other Departments of
+    Life: Legal and Political Administration, Education, and the
+    Church--Conflict of Reason and Dogma--Anthropism--Cosmological
+    Perspective--Cosmological Theorems--Refutation of the Delusion
+    of Man's Importance--Number of "World-Riddles"--Criticism of
+    the "Seven" Enigmas--The Way to Solve Them--Function of the
+    Senses and of the Brain--Induction and Deduction--Reason,
+    Sentiment, and Revelation--Philosophy and Science--Experience and
+    Speculation--Dualism and Monism
+
+
+The close of the nineteenth century offers one of the most remarkable
+spectacles to the thoughtful observer. All educated people are
+agreed that it has in many respects immeasurably outstripped its
+predecessors, and has achieved tasks that were deemed impracticable at
+its commencement. An entirely new character has been given to the whole
+of our modern civilization, not only by our astounding theoretical
+progress in sound knowledge of nature, but also by the remarkably
+fertile practical application of that knowledge in technical science,
+industry, commerce, and so forth. On the other hand, however, we have
+made little or no progress in moral and social life, in comparison with
+earlier centuries; at times there has been serious reaction. And from
+this obvious conflict there have arisen, not only an uneasy sense of
+dismemberment and falseness, but even the danger of grave catastrophes
+in the political and social world. It is, then, not merely the right,
+but the sacred duty, of every honorable and humanitarian thinker to
+devote himself conscientiously to the settlement of that conflict,
+and to warding off the dangers that it brings in its train. In our
+conviction this can only be done by a courageous effort to attain the
+truth, and by the formation of a clear view of the world--a view that
+shall be based on truth and conformity to reality.
+
+If we recall to mind the imperfect condition of science at the
+beginning of the century, and compare this with the magnificent
+structure of its closing years, we are compelled to admit that
+marvellous progress has been made during its course. Every single
+branch of science can boast that it has, especially during the latter
+half of the century, made numerous acquisitions of the utmost value.
+Both in our microscopic knowledge of the little and in our telescopic
+investigation of the great we have attained an invaluable insight
+that seemed inconceivable a hundred years ago. Improved methods of
+microscopic and biological research have not only revealed to us an
+invisible world of living things in the kingdom of the protists, full
+of an infinite wealth of forms, but they have taught us to recognize in
+the tiny cell the all-pervading "elementary organism" of whose social
+communities--the tissues--the body of every multicellular plant and
+animal, even that of man, is composed. This anatomical knowledge is
+of extreme importance; and it is supplemented by the embryological
+discovery that each of the higher multicellular organisms is developed
+out of one simple cell, the impregnated ovum. The "cellular theory,"
+which has been founded on that discovery, has given us the first true
+interpretation of the physical, chemical, and even the psychological
+processes of life--those mysterious phenomena for whose explanation
+it had been customary to postulate a supernatural "vital force" or
+"immortal soul." Moreover, the true character of disease has been made
+clear and intelligible to the physician for the first time by the
+cognate science of Cellular Pathology.
+
+The discoveries of the nineteenth century in the inorganic world are no
+less important. Physics has made astounding progress in every section
+of its province--in optics and acoustics, in magnetism and electricity,
+in mechanics and thermo-dynamics; and, what is still more important,
+it has proved the unity of the forces of the entire universe. The
+mechanical theory of heat has shown how intimately they are connected,
+and how each can, in certain conditions, transform itself directly
+into another. Spectral analysis has taught us that the same matter
+which enters into the composition of all bodies on earth, including
+its living inhabitants, builds up the rest of the planets, the sun,
+and the most distant stars. Astro-physics has considerably enlarged
+our cosmic perspective in revealing to us, in the immeasurable depths
+of space, millions of circling spheres larger than our earth, and,
+like it, in endless transformation, in an eternal rhythm of life and
+death. Chemistry has introduced us to a multitude of new substances,
+all of which arise from the combination of a few (about seventy)
+elements that are incapable of further analysis; some of them play a
+most important part in every branch of life. It has been shown that one
+of these elements--carbon--is the remarkable substance that effects
+the endless variety of organic syntheses, and thus may be considered
+"the chemical basis of life." All the particular advances, however, of
+physics and chemistry yield in theoretical importance to the discovery
+of the great law which brings them all to one common focus, the "Law
+of Substance." As this fundamental cosmic law establishes the eternal
+persistence of matter and force, their unvarying constancy throughout
+the entire universe, it has become the pole-star that guides our
+Monistic Philosophy through the mighty labyrinth to a solution of the
+world-problem.
+
+Since we intend to make a general survey of the actual condition of
+our knowledge of nature and its progress during the present century in
+the following chapters, we shall delay no longer with the review of
+its particular branches. We would only mention one important advance,
+which was contemporary with the discovery of the law of substance, and
+which supplements it--the establishment of the theory of evolution.
+It is true that there were philosophers who spoke of the evolution
+of things a thousand years ago; but the recognition that such a law
+dominates the entire universe, and that the world is nothing else than
+an eternal "evolution of substance," is a fruit of the nineteenth
+century. It was not until the second half of this century that it
+attained to perfect clearness and a universal application. The immortal
+merit of establishing the doctrine on an empirical basis, and pointing
+out its world-wide application, belongs to the great scientist Charles
+Darwin; he it was who, in 1859, supplied a solid foundation for the
+theory of descent, which the able French naturalist Jean Lamarck had
+already sketched in its broad outlines in 1809, and the fundamental
+idea of which had been almost prophetically enunciated in 1799 by
+Germany's greatest poet and thinker, Wolfgang Goethe. In that theory we
+have the key to "the question of all questions," to the great enigma
+of "the place of man in nature," and of his natural development. If we
+are in a position to-day to recognize the sovereignty of the law of
+evolution--and, indeed, of a monistic evolution--in every province of
+nature, and to use it, in conjunction with the law of substance, for a
+simple interpretation of all natural phenomena, we owe it chiefly to
+those three distinguished naturalists; they shine as three stars of the
+first magnitude amid all the great men of the century.
+
+This marvellous progress in a theoretical knowledge of nature has
+been followed by a manifold practical application in every branch
+of civilized life. If we are to-day in the "age of commerce," if
+international trade and communication have attained dimensions beyond
+the conception of any previous age, if we have transcended the limits
+of space and time by our telegraph and telephone, we owe it, in the
+first place, to the technical advancement of physics, especially in
+the application of steam and electricity. If, in photography, we can,
+with the utmost ease, compel the sunbeam to create for us in a moment's
+time a correct picture of any object we like; if we have made enormous
+progress in agriculture, and in a variety of other pursuits; if, in
+surgery, we have brought an infinite relief to human pain by our
+chloroform and morphia, our antiseptics and serous therapeutics, we
+owe it all to applied chemistry. But it is so well known how much we
+have surpassed all earlier centuries through these and other scientific
+discoveries that we need linger over the question no longer.
+
+While we look back with a just pride on the immense progress of the
+nineteenth century in a knowledge of nature and in its practical
+application, we find, unfortunately, a very different and far from
+agreeable picture when we turn to another and not less important
+province of modern life. To our great regret we must endorse the words
+of Alfred Wallace: "Compared with our astounding progress in physical
+science and its practical application, our system of government, of
+administrative justice, and of national education, and our entire
+social and moral organization, remain in a state of barbarism." To
+convince ourselves of the truth of this grave indictment we need only
+cast an unprejudiced glance at our public life, or look into the mirror
+that is daily offered to us by the press, the organ of public sentiment.
+
+We begin our review with justice, the _fundamentum regnorum_. No one
+can maintain that its condition to-day is in harmony with our advanced
+knowledge of man and the world. Not a week passes in which we do not
+read of judicial decisions over which every thoughtful man shakes his
+head in despair; many of the decisions of our higher and lower courts
+are simply unintelligible. We are not referring in the treatment of
+this particular "world-problem" to the fact that many modern states, in
+spite of their paper constitutions, are really governed with absolute
+despotism, and that many who occupy the bench give judgment less in
+accordance with their sincere conviction than with wishes expressed
+in higher quarters. We readily admit that the majority of judges and
+counsel decide conscientiously, and err simply from human frailty.
+Most of their errors, indeed, are due to defective preparation. It is
+popularly supposed that these are just the men of highest education,
+and that on that very account they have the preference in nominations
+to different offices. However, this famed "legal education" is for the
+most part rather of a formal and technical character. They have but a
+superficial acquaintance with that chief and peculiar object of their
+activity, the human organism, and its most important function, the
+mind. That is evident from the curious views as to the liberty of the
+will, responsibility, etc., which we encounter daily. I once told an
+eminent jurist that the tiny spherical ovum from which every man is
+developed is as truly endowed with life as the embryo of two, or seven,
+or even nine months; he laughed incredulously. Most of the students
+of jurisprudence have no acquaintance with anthropology, psychology,
+and the doctrine of evolution--the very first requisites for a correct
+estimate of human nature. They have "no time" for it; their time is
+already too largely bespoken for an exhaustive study of beer and wine
+and for the noble art of fencing. The rest of their valuable study-time
+is required for the purpose of learning some hundreds of paragraphs of
+law books, a knowledge of which is supposed to qualify the jurist for
+any position whatever in our modern civilized community.
+
+We shall touch but lightly on the unfortunate province of politics, for
+the unsatisfactory condition of the modern political world is only too
+familiar. In a great measure its evils are due to the fact that most of
+our officials are jurists--that is, men of high technical education,
+but utterly devoid of that thorough knowledge of human nature which is
+only obtained by the study of comparative anthropology and the monistic
+psychology--men without an acquaintance with those social relations of
+which we find the earlier types in comparative zoology and the theory
+of evolution, in the cellular theory, and the study of the protists. We
+can only arrive at a correct knowledge of the structure and life of the
+social body, the state, through a scientific knowledge of the structure
+and life of the individuals who compose it, and the cells of which they
+are in turn composed. If our political rulers and our "representatives
+of the people" possessed this invaluable biological and anthropological
+knowledge, we should not find our journals so full of the sociological
+blunders and political nonsense which at present are far from adorning
+our parliamentary reports, and even many of our official documents.
+Worst of all is it when the modern state flings itself into the arms
+of the reactionary Church, and when the narrow-minded self-interest
+of parties and the infatuation of short-sighted party-leaders lend
+their support to the hierarchy. Then are witnessed such sad scenes
+as the German Reichstag puts before our eyes even at the close of
+the nineteenth century. We have the spectacle of the educated German
+people in the power of the ultramontane Centre, under the rule of the
+Roman papacy, which is its bitterest and most dangerous enemy. Then
+superstition and stupidity reign instead of right and reason. Never
+will our government improve until it casts off the fetters of the
+Church and raises the views of the citizens on man and the world to a
+higher level by a general scientific education. That does not raise
+the question of any special form of constitution. Whether a monarchy
+or a republic be preferable, whether the constitution should be
+aristocratic or democratic, are subordinate questions in comparison
+with the supreme question: Shall the modern civilized state be
+spiritual or secular? Shall it be _theocratic_--ruled by the irrational
+formulæ of faith and by clerical despotism--or _nomocratic_--under the
+sovereignty of rational laws and civic right? The first task is to
+kindle a rational interest in our youth, and to uplift our citizens
+and free them from superstition. That can only be achieved by a timely
+reform of our schools.
+
+Our education of the young is no more in harmony with modern scientific
+progress than our legal and political world. Physical science, which
+is so much more important than all other sciences, and which, properly
+understood, really embraces all the so-called moral sciences, is still
+regarded as a mere accessory in our schools, if not treated as the
+Cinderella of the curriculum. Most of our teachers still give the
+most prominent place to that dead learning which has come down from
+the cloistral schools of the Middle Ages. In the front rank we have
+grammatical gymnastics and an immense waste of time over a "thorough
+knowledge" of classics and of the history of foreign nations. Ethics,
+the most important object of practical philosophy, is entirely
+neglected, and its place is usurped by the ecclesiastical creed. Faith
+must take precedence over knowledge--not that scientific faith which
+leads to a monistic religion, but the irrational superstition that
+lays the foundation of a perverted Christianity. The valuable teaching
+of modern cosmology and anthropology, of biology and evolution, is
+most inadequately imparted, if not entirely unknown, in our higher
+schools; while the memory is burdened with a mass of philological and
+historical facts which are utterly useless, either from the point of
+view of theoretical education or for the practical purposes of life.
+Moreover, the antiquated arrangements and the distribution of faculties
+in the universities are just as little in harmony with the point we
+have reached in monistic science as the curriculum of the primary and
+secondary schools.
+
+The climax of the opposition to modern education and its foundation,
+advanced natural philosophy, is reached, of course, in the Church. We
+are not speaking here of ultramontane papistry, nor of the orthodox
+evangelical tendencies, which do not fall far short of it in ignorance
+and in the crass superstition of their dogmas. We are imagining
+ourselves for the moment to be in the church of a liberal Protestant
+minister, who has a good average education, and who finds room for
+"the rights of reason" by the side of his faith. There, besides
+excellent moral teaching, which is in perfect harmony with our own
+monistic ethics, and humanitarian discussion of which we cordially
+approve, we hear ideas on the nature of God, of the world, of man, and
+of life which are directly opposed to all scientific experience. It
+is no wonder that physicists and chemists, doctors and philosophers,
+who have made a thorough study of nature, refuse a hearing to such
+preachers. Our theologians and our politicians are just as ignorant
+as our philosophers and our jurists of that elementary knowledge of
+nature which is based on the monistic theory of evolution, and which is
+already far exceeded in the triumph of our modern learning.
+
+From this opposition, which we can only briefly point out at present,
+there arise grave conflicts in our modern life which urgently demand
+a settlement. Our modern education, the outcome of our great advance
+in knowledge, has a claim upon every department of public and private
+life; it would see humanity raised, by the instrumentality of
+reason, to that higher grade of culture, and, consequently, to that
+better path towards happiness which has been opened out to us by the
+progress of modern science. That aim, however, is vigorously opposed
+by the influential parties who would detain the mind in the exploded
+views of the Middle Ages with regard to the most important problems
+of life; they linger in the fold of traditional dogma, and would
+have reason prostrate itself before their "higher revelation." That
+is the condition of things, to a very large extent, in theology and
+philosophy, in sociology and jurisprudence. It is not that the motives
+of the latter are to be attributed, as a rule, to pure self-interest;
+they spring partly from ignorance of the facts, and partly from an
+indolent acquiescence in tradition. The most dangerous of the three
+great enemies of reason and knowledge is not malice; but ignorance, or,
+perhaps, indolence. The gods themselves still strive in vain against
+these two latter influences when they have happily vanquished the first.
+
+One of the main supports of that reactionary system is still what
+we may call "anthropism." I designate by this term "that powerful
+and world-wide group of erroneous opinions which opposes the human
+organism to the whole of the rest of nature, and represents it to be
+the preordained end of the organic creation, an entity essentially
+distinct from it, a godlike being." Closer examination of this group of
+ideas shows it to be made up of three different dogmas, which we may
+distinguish as the _anthropocentric_, the _anthropomorphic_, and the
+_anthropolatrous_.[4]
+
+I. The _anthropocentric_ dogma culminates in the idea that man
+is the preordained centre and aim of all terrestrial life--or, in
+a wider sense, of the whole universe. As this error is extremely
+conducive to man's interest, and as it is intimately connected with the
+creation-myth of the three great Mediterranean religions, and with the
+dogmas of the Mosaic, Christian, and Mohammedan theologies, it still
+dominates the greater part of the civilized world.
+
+II. The _anthropomorphic_ dogma is likewise connected with the
+creation-myth of the three aforesaid religions, and of many others. It
+likens the creation and control of the world by God to the artificial
+creation of a talented engineer or mechanic, and to the administration
+of a wise ruler. God, as creator, sustainer, and ruler of the world,
+is thus represented after a purely human fashion in his thought and
+work. Hence it follows, in turn, that man is godlike. "God made man
+to His own image and likeness." The older, naïve mythology is pure
+"homotheism," attributing human shape, flesh, and blood to the gods.
+It is more intelligible than the modern mystic theosophy that adores
+a personal God as an invisible--properly speaking, gaseous--being,
+yet makes him think, speak, and act in human fashion; it gives us the
+paradoxical picture of a "gaseous vertebrate."
+
+III. The _anthropolatric_ dogma naturally results from this comparison
+of the activity of God and man; it ends in the apotheosis of the human
+organism. A further result is the belief in the personal immortality of
+the soul, and the dualistic dogma of the twofold nature of man, whose
+"immortal soul" is conceived as but the temporary inhabitant of the
+mortal frame. Thus these three anthropistic dogmas, variously adapted
+to the respective professions of the different religions, came at
+length to be vested with an extraordinary importance, and proved the
+source of the most dangerous errors. The anthropistic view of the world
+which springs from them is in irreconcilable opposition to our monistic
+system; indeed, it is at once disproved by our new cosmological
+perspective.
+
+Not only the three anthropistic dogmas, but many other notions of the
+dualistic philosophy and orthodox religion, are found to be untenable
+as soon as we regard them critically from the cosmological perspective
+of our monistic system. We understand by that the comprehensive view
+of the universe which we have from the highest point of our monistic
+interpretation of nature. From that stand-point we see the truth of the
+following "cosmological theorems," most of which, in our opinion, have
+already been amply demonstrated:
+
+(1) The universe, or the cosmos, is eternal, infinite, and illimitable.
+(2) Its substance, with its two attributes (matter and energy), fills
+infinite space, and is in eternal motion. (3) This motion runs on
+through infinite time as an unbroken development, with a periodic
+change from life to death, from evolution to devolution. (4) The
+innumerable bodies which are scattered about the space-filling ether
+all obey the same "law of substance;" while the rotating masses slowly
+move towards their destruction and dissolution in one part of space
+others are springing into new life and development in other quarters
+of the universe. (5) Our sun is one of these unnumbered perishable
+bodies, and our earth is one of the countless transitory planets that
+encircle them. (6) Our earth has gone through a long process of cooling
+before water, in liquid form (the first condition of organic life),
+could settle thereon. (7) The ensuing biogenetic process, the slow
+development and transformation of countless organic forms, must have
+taken many millions of years--considerably over a hundred.[5] (8) Among
+the different kinds of animals which arose in the later stages of the
+biogenetic process on earth the vertebrates have far outstripped all
+other competitors in the evolutionary race. (9) The most important
+branch of the vertebrates, the mammals, were developed later (during
+the triassic period) from the lower amphibia and the reptilia. (10) The
+most perfect and most highly developed branch of the class mammalia is
+the order of primates, which first put in an appearance, by development
+from the lowest prochoriata, at the beginning of the Tertiary
+period--at least three million years ago. (11) The youngest and most
+perfect twig of the branch primates is man, who sprang from a series of
+manlike apes towards the end of the Tertiary period. (12) Consequently,
+the so-called "history of the world"--that is, the brief period of a
+few thousand years which measures the duration of civilization--is an
+evanescently short episode in the long course of organic evolution,
+just as this, in turn, is merely a small portion of the history of
+our planetary system; and as our mother-earth is a mere speck in the
+sunbeam in the illimitable universe, so man himself is but a tiny grain
+of protoplasm in the perishable framework of organic nature.
+
+Nothing seems to me better adapted than this magnificent cosmological
+perspective to give us the proper standard and the broad outlook
+which we need in the solution of the vast enigmas that surround us.
+It not only clearly indicates the true place of man in nature, but it
+dissipates the prevalent illusion of man's supreme importance, and
+the arrogance with which he sets himself apart from the illimitable
+universe, and exalts himself to the position of its most valuable
+element. This boundless presumption of conceited man has misled him
+into making himself "the image of God," claiming an "eternal life" for
+his ephemeral personality, and imagining that he possesses unlimited
+"freedom of will." The ridiculous imperial folly of Caligula is but
+a special form of man's arrogant assumption of divinity. Only when
+we have abandoned this untenable illusion, and taken up the correct
+cosmological perspective, can we hope to reach the solution of the
+"riddles of the universe."
+
+The uneducated member of a civilized community is surrounded with
+countless enigmas at every step, just as truly as the savage. Their
+number, however, decreases with every stride of civilization and of
+science; and the monistic philosophy is ultimately confronted with but
+one simple and comprehensive enigma--the "problem of substance." Still,
+we may find it useful to include a certain number of problems under
+that title. In the famous speech which Emil du Bois-Reymond delivered
+in 1880, in the Leibnitz session of the Berlin Academy of Sciences,
+he distinguished seven world-enigmas, which he enumerated as follows:
+(1) The nature of matter and force. (2) The origin of motion. (3) The
+origin of life. (4) The (apparently preordained) orderly arrangement
+of nature. (5) The origin of simple sensation and consciousness. (6)
+Rational thought, and the origin of the cognate faculty, speech. (7)
+The question of the freedom of the will. Three of these seven enigmas
+are considered by the orator of the Berlin Academy to be entirely
+transcendental and insoluble--they are the first, second, and fifth;
+three others (the third, fourth, and sixth) he considers to be capable
+of solution, though extremely difficult; as to the seventh and last
+"world-enigma," the freedom of the will, which is the one of the
+greatest practical importance, he remains undecided.
+
+As my monism differs materially from that of the Berlin orator, and as
+his idea of the "seven great enigmas" has been very widely accepted,
+it may be useful to indicate their true position at once. In my
+opinion, the three transcendental problems (1, 2, and 5) are settled
+by our conception of substance (_vide_ chap. xii.); the three which
+he considers difficult, though soluble, (3, 4, and 6), are decisively
+answered by our modern theory of evolution; the seventh and last, the
+freedom of the will, is not an object for critical, scientific inquiry
+at all, for it is a pure dogma, based on an illusion, and has no real
+existence.
+
+The means and methods we have chosen for attaining the solution of the
+great enigma do not differ, on the whole, from those of all purely
+scientific investigation--firstly, experience; secondly, inference.
+Scientific experience comes to us by observation and experiment, which
+involve the activity of our sense-organs in the first place, and,
+secondly, of the inner sense-centres in the cortex of the brain. The
+microscopic elementary organs of the former are the sense-cells; of the
+latter, groups of ganglionic cells. The experiences which we derive
+from the outer world by these invaluable instruments of our mental life
+are then moulded into ideas by other parts of the brain, and these,
+in their turn, are united in a chain of reasoning by association. The
+construction of this chain may take place in two different ways, which
+are, in my opinion, equally valuable and indispensable: _induction_
+and _deduction_. The higher cerebral operations, the construction
+of complicated chains of reasoning, abstraction, the formation of
+concepts, the completion of the perceptive faculty by the plastic
+faculty of the imagination--in a word, consciousness, thought, and
+speculation--are functions of the ganglionic cells of the cortex of the
+brain, just like the preceding simpler mental functions. We unite them
+all in the supreme concept of _reason_.[6]
+
+By reason only can we attain to a correct knowledge of the world and a
+solution of its great problems. Reason is man's highest gift, the only
+prerogative that essentially distinguishes him from the lower animals.
+Nevertheless, it has only reached this high position by the progress of
+culture and education, by the development of knowledge. The uneducated
+man and the savage are just as little (or just as much) "rational"
+as our nearest relatives among the mammals (apes, dogs, elephants,
+etc.). Yet the opinion still obtains in many quarters that, besides
+our godlike reason, we have two further (and even surer!) methods of
+receiving knowledge--emotion and revelation. We must at once dispose
+of this dangerous error. Emotion has nothing whatever to do with the
+attainment of truth. That which we prize under the name of "emotion"
+is an elaborate activity of the brain, which consists of feelings of
+like and dislike, motions of assent and dissent, impulses of desire and
+aversion. It may be influenced by the most diverse activities of the
+organism, by the cravings of the senses and the muscles, the stomach,
+the sexual organs, etc. The interests of truth are far from promoted
+by these conditions and vacillations of emotion; on the contrary, such
+circumstances often disturb that reason which alone is adapted to the
+pursuit of truth, and frequently mar its perceptive power. No cosmic
+problem is solved, or even advanced, by the cerebral function we call
+emotion. And the same must be said of the so-called "revelation," and
+of the "truths of faith" which it is supposed to communicate; they are
+based entirely on a deception, consciously or unconsciously, as we
+shall see in the sixteenth chapter.
+
+We must welcome as one of the most fortunate steps in the direction
+of a solution of the great cosmic problems the fact that of recent
+years there is a growing tendency to recognize the two paths which
+alone lead thereto--_experience_ and _thought_, or _speculation_--to
+be of equal value, and mutually complementary. Philosophers have come
+to see that pure speculation--such, for instance, as Plato and Hegel
+employed for the construction of their _idealist_ systems--does not
+lead to knowledge of reality. On the other hand, scientists have been
+convinced that mere experience--such as Bacon and Mill, for example,
+made the basis of their _realist_ systems--is insufficient of itself
+for a complete philosophy. For these two great paths of knowledge,
+sense-experience and rational thought, are two distinct cerebral
+functions; the one is elaborated by the sense-organs and the inner
+sense-centres, the other by the thought-centres, the great "centres
+of association in the cortex of the brain," which lie between the
+sense-centres. (Cf. cc. vii. and x.) True knowledge is only acquired
+by combining the activity of the two. Nevertheless, there are still
+many philosophers who would construct the world out of their own
+inner consciousness, and who reject our empirical science precisely
+because they have no knowledge of the real world. On the other hand,
+there are many scientists who still contend that the sole object of
+science is "the knowledge of facts, the objective investigation of
+isolated phenomena"; that "the age of philosophy" is past, and science
+has taken its place.[7] This one-sided over-estimation of experience
+is as dangerous an error as the converse exaggeration of the value of
+speculation. Both channels of knowledge are mutually indispensable.
+The greatest triumphs of modern science--the cellular theory, the
+dynamic theory of heat, the theory of evolution, and the law of
+substance--are _philosophic achievements_; not, however, the fruit of
+pure speculation, but of an antecedent experience of the widest and
+most searching character.
+
+At the commencement of the nineteenth century the great idealistic
+poet, Schiller, gave his counsel to both groups of combatants, the
+philosophers and the scientists:
+
+    "Does strife divide your efforts--no union bless your toil?
+    Will truth e'er be delivered if ye your forces rend?"
+
+Since then the situation has, happily, been profoundly modified; while
+both schools, in their different paths, have pressed onward towards the
+same high goal, they have recognized their common aspiration, and they
+draw nearer to a knowledge of the truth in mutual covenant. At the end
+of the nineteenth century we have returned to that monistic attitude
+which our greatest realistic poet, Goethe, had recognized from its very
+commencement to be alone correct and fruitful.[8]
+
+All the different philosophical tendencies may, from the point of
+view of modern science, be ranged in two antagonistic groups; they
+represent either a _dualistic_ or a _monistic_ interpretation of
+the cosmos. The former is usually bound up with teleological and
+idealistic dogmas, the latter with mechanical and realistic theories.
+Dualism, in the widest sense, breaks up the universe into two entirely
+distinct substances--the material world and an immaterial God, who
+is represented to be its creator, sustainer, and ruler. Monism, on
+the contrary (likewise taken in its widest sense), recognizes one
+sole substance in the universe, which is at once "God and nature";
+body and spirit (or matter and energy) it holds to be inseparable.
+The extramundane God of dualism leads necessarily to theism; and the
+intra-mundane God of the monist leads to pantheism.
+
+The different ideas of _monism_ and _materialism_, and likewise
+the essentially distinct tendencies of theoretical and practical
+materialism, are still very frequently confused. As this and other
+similar cases of confusion of ideas are very prejudicial, and give rise
+to innumerable errors, we shall make the following brief observations,
+in order to prevent misunderstanding:
+
+I. Pure monism is identical neither with the theoretical materialism
+that denies the existence of spirit, and dissolves the world into a
+heap of dead atoms, nor with the theoretical spiritualism (lately
+entitled "energetic" spiritualism by Ostwald) which rejects the notion
+of matter, and considers the world to be a specially arranged group of
+"energies" or immaterial natural forces.
+
+II. On the contrary, we hold, with Goethe, that "matter cannot exist
+and be operative without spirit, nor spirit without matter." We
+adhere firmly to the pure, unequivocal monism of Spinoza: Matter, or
+infinitely extended substance, and spirit (or energy), or sensitive and
+thinking substance, are the two fundamental attributes or principal
+properties of the all-embracing divine essence of the world, the
+universal substance. (Cf. chap. xii.)
+
+
+
+
+CHAPTER II
+
+OUR BODILY FRAME
+
+    Fundamental Importance of Anatomy--Human Anatomy--Hippocrates,
+    Aristotle, Galen, Vesalius--Comparative Anatomy--Georges
+    Cuvier--Johannes Müller--Karl Gegenbaur--Histology--The Cellular
+    Theory--Schleiden and Schwann--Kölliker--Virchow--Man a
+    Vertebrate, a Tetrapod, a Mammal, a Placental, a Primate--Prosimiæ
+    and Simiæ--The Catarrhinæ--Papiomorphic and Anthropomorphic
+    Apes--Essential Likeness of Man and the Ape in Corporal Structure
+
+
+All biological research, all investigation into the forms and vital
+activities of organisms, must first deal with the visible body, in
+which the morphological and physiological phenomena are observed. This
+fundamental rule holds good for man just as much as for all other
+living things. Moreover, the inquiry must not confine itself to mere
+observation of the outer form; it must penetrate to the interior, and
+study both the general plan and the minute details of the structure.
+The science which pursues this fundamental investigation in the
+broadest sense is anatomy.
+
+The first stimulus to an inquiry into the human frame arose, naturally,
+in medicine. As it was usually practised by the priests in the older
+civilizations, we may assume that these highest representatives of
+the education of the time had already acquired a certain amount
+of anatomical knowledge two thousand years before Christ, or even
+earlier. We do not, however, find more exact observations, founded
+on the dissection of mammals, and applied, by analogy, to the human
+frame, until we come to the Greek scientists of the sixth and fifth
+centuries before Christ--Empedocles (of Agrigentum) and Democritus
+(of Abdera), and especially the most famous physician of classic
+antiquity, Hippocrates (of Cos). It was from these and other sources
+that the great Aristotle, the renowned "father of natural history,"
+equally comprehensive as investigator and philosopher, derived his
+first knowledge. After him only one anatomist of any consequence is
+found in antiquity, the Greek physician Claudius Galenus (of Pergamus),
+who developed a wealthy practice in Rome in the second century after
+Christ, under the Emperor Marcus Aurelius. All these ancient anatomists
+acquired their knowledge, as a rule, not by the dissection of the human
+body itself--which was then sternly forbidden--but by a study of the
+bodies of the animals which most closely resembled man, especially the
+apes; they were all, indeed, comparative anatomists.
+
+The triumph of Christianity and its mystic theories meant retrogression
+to anatomy, as it did to all the other sciences. The popes were
+resolved above all things to detain humanity in ignorance; they rightly
+deemed a knowledge of the human organism to be a dangerous source
+of enlightenment as to our true nature. During the long period of
+thirteen centuries the writings of Galen were almost the only source
+of human anatomy, just as the works of Aristotle were for the whole
+of natural history. It was not until the sixteenth century, when the
+spiritual tyranny of the papacy was broken by the Reformation, and the
+geocentric theory, so intimately connected with papal doctrine, was
+destroyed by the new cosmic system of Copernicus, that the knowledge
+of the human frame entered upon a new period of progress. The great
+anatomists, Vesalius (of Brussels), and Eustachius and Fallopius
+(of Modena), advanced the knowledge of our bodily structure so much
+by their own thorough investigations that little remained for their
+numerous followers to do, with regard to the more obvious phenomena,
+except the substantiation of details. Andreas Vesalius, as courageous
+as he was talented and indefatigable, was the pioneer of the movement;
+he completed in his twenty-eighth year (1543) that great and systematic
+work _De humani corporis fabrica_; he gave to the whole of human
+anatomy a new and independent scope and a more solid foundation. On
+that account he was, at a later date, at Madrid--where he was physician
+to Charles V. and Philip II.--condemned to death by the Inquisition as
+a magician. He only escaped by undertaking a pilgrimage to Jerusalem;
+in returning he suffered shipwreck on the Isle of Zante, and died there
+in misery and destitution.
+
+The great merit of the nineteenth century, as far as our knowledge of
+the human frame is concerned, lies in the founding of two new lines
+of research of immense importance--comparative anatomy and histology,
+or microscopic anatomy. The former was intimately associated with
+human anatomy from the very beginning; indeed, it had to supply the
+place of the latter so long because the dissection of human corpses
+was a crime visited with capital punishment--that was the case even
+in the fifteenth century! But the many anatomists of the next three
+centuries devoted themselves mainly to a more accurate study of the
+human organism. The elaborate science which we now call comparative
+anatomy was born in the year 1803, when the great French zoologist
+Georges Cuvier (a native of Mömpelgard, in Alsace) published his
+profound _Leçons sur l'anatomie comparée_, and endeavored to formulate,
+for the first time, definite laws as to the organism of man and the
+beasts. While his predecessors--among whom was Goethe in 1790--had
+mainly contented themselves with comparing the skeleton of man with
+those of other animals, Cuvier's broader vision took in the whole
+of the animal organization. He distinguished therein four great and
+mutually independent types: Vertebrata, Articulata, Mollusca, and
+Radiata. This advance was of extreme consequence for our "question
+of all questions," since it clearly brought out the fact that man
+belonged to the vertebral type, and differed fundamentally from all
+the other types. It is true that the keen-sighted Linné had already,
+in his _Systema Natuae_, made a great step in advance by assigning
+man a definite place in the class of mammals; he had even drawn up
+the three groups of half-apes, apes, and men (_Lemur_, _simia_, and
+_homo_) in the order of primates. But his keen, systematic mind was
+not furnished with that profound empirical foundation, supplied by
+comparative anatomy, which Cuvier was the first to attain. Further
+developments were added by the great comparative anatomists of our own
+century--Friedrich Meckel (Halle), Johannes Müller (Berlin), Richard
+Owen, T. Huxley, and Karl Gegenbaur (Jena, subsequently Heidelberg).
+The last-named, in applying the evolutionary theory, which Darwin had
+just established, to comparative anatomy, raised his science to the
+front rank of biological studies. The numerous comparative anatomical
+works of Gegenbaur are, like his well-known _Manual of Human Anatomy_,
+equally distinguished by a thorough empirical acquaintance with their
+immense multitudes of facts, and by a comprehensive control of his
+material, and its philosophic appreciation in the evolutionary sense.
+His recent _Comparative Anatomy of the Vertebrata_ establishes the
+solid foundation on which our conviction of the vertebral character of
+man in every aspect is chiefly based.
+
+Microscopic anatomy has been developed, in the course of the present
+century, in a very different fashion from comparative anatomy. At
+the beginning of the century (1802) a French physician, Bichat, made
+an attempt to dissect the organs of the human body into their finer
+constituents by the aid of the microscope, and to show the connection
+of these various _tissues_ (_hista_, or _tela_). This first attempt
+led to little result, because the scientist was ignorant of the one
+common element of all the different tissues. This was first discovered
+(1838) in the shape of the _cell_, in the plant world, by Matthias
+Schleiden, and immediately afterwards proved to be the same in the
+animal world by Theodor Schwann, the pupil and assistant of Johannes
+Müller at Berlin. Two other distinguished pupils of this great master,
+who are still living, Albert Kölliker and Rudolph Virchow, took up
+the cellular theory, and the theory of tissues which is founded on
+it, in the sixties, and applied them to the human organism in all its
+details, both in health and disease; they proved that, in man and
+all other animals, every tissue is made up of the same microscopic
+particles, the _cells_, and these "elementary organisms" are the real,
+self-active citizens which, in combinations of millions, constitute
+the "cellular state," our body. All these cells spring from one simple
+cell, the _cytula_, or impregnated ovum, by continuous subdivision.
+The general structure and combination of the tissues are the same in
+man as in the other vertebrates. Among these the mammals, the youngest
+and most highly developed class take precedence, in virtue of certain
+special features which were acquired late. Such are, for instance, the
+microscopic texture of the hair, of the glands of the skin, and of the
+breasts, and the corpuscles of the blood, which are quite peculiar to
+mammals, and different from those of the other vertebrates; man, even
+in these finest histological relations, is a _true mammal_.
+
+The microscopic researches of Albert Kölliker and Franz Leydig (at
+Würzburg) not only enlarged our knowledge of the finer structure of man
+and the beasts in every direction, but they were especially important
+in the light of their connection with the evolution of the cell and
+the tissue; they confirmed the great theory of Carl Theodor Siebold
+(1845) that the lowest animals, the Infusoria and the Rhizopods, are
+unicellular organisms.
+
+Our whole frame, both in its general plan and its detailed structure,
+presents the characteristic type of the vertebrates. This most
+important and most highly developed group in the animal world was
+first recognized in its natural unity in 1801 by the great Lamarck;
+he embraced under that title the four higher animal groups of
+Linné--mammals, birds, amphibia, and fishes. To these he opposed the
+two lower classes, insects and worms, as invertebrates. Cuvier (1812)
+established the unity of the vertebrate type on a firmer basis by
+his comparative anatomy. It is quite true that all the vertebrates,
+from the fish up to man, agree in every essential feature; they all
+have a firm internal skeleton, a framework of cartilage and bone,
+consisting principally of a vertebral column and a skull; the advanced
+construction of the latter presents many variations, but, on the whole,
+all may be reduced to the same fundamental type. Further, in all
+vertebrates the "organ of the mind," the central nervous system, in
+the shape of a spinal cord and a brain, lies at the back of this axial
+skeleton. Moreover, what we said of its bony environment, the skull,
+is also true of the brain--the instrument of consciousness and all the
+higher functions of the mind; its construction and size present very
+many variations in detail, but its general characteristic structure
+remains always the same.
+
+We meet the same phenomenon when we compare the rest of our organs with
+those of the other vertebrates; everywhere, in virtue of heredity,
+the original plan and the relative distribution of the organs remain
+the same, although, through adaptation to different environments,
+the size and the structure of particular sections offer considerable
+variation. Thus we find that in all cases the blood circulates in
+two main blood-vessels, of which one--the aorta--passes over the
+intestine, and the other--the principal vein--passes underneath, and
+that by the broadening out of the latter in a very definite spot a
+heart has arisen; this "ventral heart" is just as characteristic of all
+vertebrates as the "dorsal heart" is of the articulata and mollusca.
+Equally characteristic of all vertebrates is the early division of
+the intestinal tube into a "head-gut" (or gill-gut), which serves in
+respiration, and a "body-gut" (or liver-gut), which co-operates with
+the liver in digestion; so are, likewise, the ramification of the
+muscular system, the peculiar structure of the urinary and sexual
+organs, and so forth. In all these anatomical relations _man is a true
+vertebrate_.
+
+Aristotle gave the name of four-footed, or tetrapoda, to all the higher
+warm-blooded animals which are distinguished by the possession of two
+pairs of legs. The category was enlarged subsequently, and its title
+changed into the Latin "quadrupeda," when Cuvier proved that even
+"two-legged" birds and men are really "four-footed"; he showed that the
+internal skeleton of the four legs in all the higher land-vertebrates,
+from the amphibia up to man, was originally constructed after the same
+pattern out of a definite number of members. The "arm" of man and the
+"wing" of bats and birds have the same typical skeleton as the foreleg
+of the animals which are conspicuously "four-footed."
+
+The anatomical unity of the fully developed skeleton in the four limbs
+of all tetrapods is very important. In order to appreciate it fully
+one has only to compare carefully the skeleton of a salamander or a
+frog with that of a monkey or a man. One perceives at once that the
+humeral zone in front and the pelvic zone behind are made up of the
+same principal parts as in the rest of the quadrupeds. We find in all
+cases that the first section of the leg proper consists of one strong
+marrow-bone (the _humerus_, in the forearm; the _femur_, behind);
+the second part, on the contrary, originally always consists of two
+bones (the _ulna_ and _radius_, in front; the _fibula_ and _tibia_,
+behind). When we further compare the developed structure of the foot
+proper we are surprised to find that the small bones of which it is
+made up are also similarly arranged and distributed in every case: in
+the front limb the three groups of bones of the forefoot (or "hand")
+correspond in all classes of the tetrapoda: (1) the _carpus_, (2)
+the _metacarpus_, (3) the five fingers (_digiti anteriores_); in the
+rear limb, similarly, we have always the same three osseous groups of
+the hind foot: (1) the _tarsus_, (2) the _metatarsus_, and (3) the
+five toes (_digiti posteriores_). It was a very difficult task to
+reduce all these little bones to one primitive type, and to establish
+the equivalence (or homology) of the separate parts in all cases;
+they present extreme variations of form and construction in detail,
+sometimes being partly fused together and losing their individuality.
+This great task was first successfully achieved by the most eminent
+comparative anatomist of our day, Karl Gegenbaur. He pointed out,
+in his _Researches into the Comparative Anatomy of the Vertebrata_
+(1864), how this characteristic "five-toed leg" of the land tetrapods
+originally (not before the Carboniferous period) arose out of the
+radiating fin (the breast-fin, or the belly-fin) of the ancient
+fishes. He had also, in his famous _Researches into the Skull of the
+Vertebrata_ (1872), deduced the younger skull of the tetrapods from the
+oldest cranial form among the fishes, that of the shark.
+
+It is especially remarkable that the original number of the toes (five)
+on each of the four feet, which first appeared in the old amphibia
+of the Carboniferous period, has, in virtue of a strict heredity,
+been preserved even to the present day in man. Also, naturally and
+harmoniously, the typical construction of the joints, ligaments,
+muscles, and nerves of the two pairs of legs has, in the main, remained
+the same as in the rest of the "four-footed." In all these important
+relations _man is a true tetrapod_.
+
+The mammals are the youngest and most advanced class of the vertebrates.
+It is true they are derived from the older class of amphibia, like
+birds and reptiles: yet they are distinguished from all the other
+tetrapods by a number of very striking anatomical features. Externally,
+there is the clothing of the skin with hair, and the possession of
+two kinds of skin glands--the sweat glands and the sebaceous glands.
+A local development of these glands on the abdominal skin gave
+rise (probably during the Triassic period) to the organ which is
+especially characteristic of the class, and from which it derives its
+name--the _mammarium_. This important instrument of lactation is made
+up of milk glands (_mammae_) and the "mammar-pouches" (folds of the
+abdominal skin); in its development the teats appear, through which
+the young mammal sucks its mother's milk. In internal structure the
+most remarkable feature is the possession of a complete diaphragm, a
+muscular wall which, in all mammals--and _only_ in mammals--separates
+the thoracic from the abdominal cavity; in all other vertebrates
+there is no such separation. The skull of mammals is distinguished
+by a number of remarkable formations, especially in the maxillary
+apparatus (the upper and lower jaws, and the temporal bones). Moreover,
+the brain, the olfactory organ, the heart, the lungs, the internal
+and external sexual organs, the kidneys, and other parts of the body
+present special peculiarities, both in general and detailed structure,
+in the mammals; all these, taken collectively, point unequivocally
+to an early derivation of the mammals from the older groups of the
+reptiles and amphibia, which must have taken place, at the latest, in
+the Triassic period--at least twelve million years ago! In all these
+important characteristics _man is a true mammal_.
+
+The numerous orders (12-33) which modern systematic zoology
+distinguishes in the class of mammals had been arranged in 1816
+(by Blainville) in three natural groups, which still hold good as
+sub-classes: (1) the monotrema, (2) the marsupialia, and (3) the
+placentalia. These three sub-classes not only differ in the important
+respect of bodily structure and development, but they correspond, also,
+to three different historical stages in the formation of the class,
+as we shall see later on. The monotremes of the Triassic period were
+followed by the marsupials of the Jurassic, and these by the placentals
+of the Cretaceous. Man belongs to this, the youngest, sub-class; for
+he presents in his organization all the features which distinguish
+the placentals from the marsupials and the still older monotremes.
+First of all, there is the peculiar organ which gives a name to the
+placentals--the _placenta_. It serves the purpose of nourishing the
+young mammal embryo for a long time during its enclosure in the
+mother's womb; it consists of blood-bearing tufts which grow out of the
+chorion surrounding the embryo, and penetrate corresponding cavities in
+the mucous membrane of the maternal uterus; the delicate skin between
+the two structures is so attenuated in this spot that the nutriment in
+the mother's blood can pass directly into the blood of the child. This
+excellent contrivance for nourishing the embryo, which makes its first
+appearance at a somewhat late date, gives the foetus the opportunity
+of a longer maintenance and a higher development in the protecting
+womb; it is wanting in the _implacentalia_, the two older sub-classes
+of the marsupials and the monotremes. There are, likewise, other
+anatomical features, particularly the higher development of the brain
+and the absence of the marsupial bone, which raise the placentals above
+all their implacental ancestors. In all these important particulars
+_man is a true placental_.
+
+The very varied sub-class of the placentals has been recently
+subdivided into a great number of orders; they are usually put at from
+ten to sixteen, but when we include the important extinct forms which
+have been recently discovered the number runs up to from twenty to
+twenty-six. In order to facilitate the study of these numerous orders,
+and to obtain a deeper insight into their kindred construction, it
+is very useful to form them into great natural groups, which I have
+called "legions." In my latest attempt[9] to arrange the advanced
+system of placentals in phylogenetic order I have substituted eight
+of these legions for the twenty-six orders, and shown that these may
+be reduced to four main groups. These, in turn, are traceable to one
+common ancestral group of all the placentals, their fossil ancestors,
+the _prochoriata_ of the Cretaceous period. These are directly
+connected with the marsupial ancestors of the Jurassic period. We
+will only specify here, as the most important living representatives
+of these four main groups, the rodentia, the ungulata, the carnivora,
+and the primates. To the legion of the primates belong the prosimiæ
+(half-apes), the simiæ (real apes), and man. All the members of these
+three orders agree in many important features, and are at the same
+time distinguished by these features from the other twenty-three
+orders of placentals. They are especially conspicuous for the length
+of their bones, which were originally adapted to their arboreal manner
+of life. Their hands and feet are five-fingered, and the long fingers
+are excellently suited for grasping and embracing the branches of
+trees; they are provided, either partially or completely, with nails,
+but have no claws. The dentition is complete, containing all four
+classes--incisors, canine, premolars, and molars. Primates are also
+distinguished from all the other placentals by important features in
+the special construction of the skull and the brain; and these are the
+more striking in proportion to their development and the lateness of
+their appearance in the history of the earth. In all these important
+anatomical features our human organism agrees with that of all the
+other primates: _man is a true primate_.
+
+An impartial and thorough comparison of the bodily structure of the
+primates forces us to distinguish two orders in this most advanced
+legion of the mammalia--half-apes (_prosimiae_ or _hemipitheci_) and
+apes (_simiae_ or _pitheci_). The former seem in every respect to be
+the lower and older, the latter to be the higher and younger order. The
+womb of the half-ape is still double, or two-horned, as it is in all
+the other mammals. In the true ape, on the contrary, the right and left
+wombs have completely amalgamated; they blend into a pear-shaped womb,
+which the human mother possesses besides the ape. In the skull of the
+apes, just as in that of man, the orbits of the eyes are completely
+separated from the temporal cavities by an osseous partition; in
+the _prosimiae_ this is either entirely wanting or very imperfect.
+Finally, the cerebrum of the _prosimia_ is either quite smooth or very
+slightly furrowed, and proportionately small; that of the true ape is
+much larger, and the gray bed especially, the organ of higher psychic
+activity, is much more developed; the characteristic convolutions
+and furrows appear on its surface exactly in proportion as the ape
+approaches to man. In these and other important respects, particularly
+in the construction of the face and the hands, _man presents all the
+anatomical marks of a true ape_.
+
+The extensive order of apes was divided by Geoffroi, in 1812, into
+two sub-orders, which are still universally accepted in systematic
+zoology--New World and Old World monkeys, according to the hemisphere
+they respectively inhabit. The American "New World" monkeys are called
+_Platyrrhinae_ (flat-nosed); their nose is flat, and the nostrils
+divergent, with a broad partition. The "Old World" monkeys, on the
+contrary, are called collectively _Catarrhinae_ (narrow-nosed); their
+nostrils point downward, like man's, and the dividing cartilage is
+narrow. A further difference between the two groups is that the
+tympanum is superficial in the _platyrrhinae_, but lies deeper,
+inside the petrous bone, in the _catarrhinae_; in the latter a long
+and narrow bony passage has been formed, while in the former it is
+still short and wide, or even altogether wanting. Finally, we have a
+much more important and decisive difference between the two groups in
+the circumstance that all the Old World monkeys have the same teeth
+as man--_i. e._, twenty deciduous and thirty-two permanent teeth
+(two incisors, one canine, two premolars, and three molars in each
+half of the jaw). The New World monkeys, on the other hand, have an
+additional premolar in each half-jaw, or thirty-six teeth altogether.
+The fact that these anatomical differences of the two simian groups
+are universal and conspicuous, and that they harmonize with their
+geographical distribution in the two hemispheres, fully authorizes
+a sharp systematic division of the two, as well as the phylogenetic
+conclusion that for a very long period (for more than a million years)
+the two sub-orders have been developing quite independently of each
+other in the western and eastern hemispheres. That is a most important
+point in view of the genealogy of our race; for man bears all the marks
+of a _true catarrhina_; he has descended from some extinct member of
+this sub-order in the Old World.
+
+The numerous types of _catarrhinae_ which still survive in Asia and
+Africa have been formed into two sections for some time--the tailed,
+doglike apes (the _cynopitheci_) and the tailless, manlike apes (the
+_anthropomorpha_). The latter are much nearer to man than the former,
+not only in the absence of a tail and in the general build of the body
+(especially of the head), but also on account of certain features
+which are unimportant in themselves but very significant in their
+constancy. The sacrum of the anthropoid ape, like that of man, is made
+up of the fusion of five vertebræ; that of the _cynopithecus_ consists
+of three (more rarely four) sacral vertebræ. The premolar teeth of
+the _cynopitheci_ are greater in length than breadth; those of the
+_anthropomorpha_ are broader than they are long; and the first molar
+has four protuberances in the former, five in the latter. Furthermore,
+the outer incisor of the lower jaw is broader than the inner one
+in the manlike apes and man; in the doglike ape it is the smaller.
+Finally, there is a special significance in the fact, established by
+Selenka in 1890, that the anthropoid apes share with man the peculiar
+structure of the discoid _placenta_, the _decidua reflexa_, and the
+pedicle of the allantois. In fact, even a superficial comparison of
+the bodily structure of the _anthropomorpha_ which still survive makes
+it clear that both the Asiatic (the orang-outang and the gibbous ape)
+and the African (the gorilla and chimpanzee) representatives of this
+group are nearer to man in build than any of the _cynopitheci_. Under
+the latter group we include the dog-faced papiomorpha, the baboon,
+and the long-tailed monkey, at a very low stage. The anatomical
+difference between these low papiomorpha and the most highly developed
+anthropoid apes is greater in every respect, whatever organ we take
+for comparison, than the difference between the latter and man.
+This instructive fact was established with great penetration by the
+anatomist Robert Hartmann, in his work on _The Anthropoid Apes_;[10]
+he proposed to divide the order of _Simiae_ in a new way--namely, into
+the two great groups of _primaria_ (man and the anthropoid ape) and the
+_simiae_ proper, or _pitheci_ (the rest of the catarrhinæ and all the
+platyrrhinæ). In any case, we have a clear proof of _the close affinity
+of man and the anthropoid ape_.
+
+Thus comparative anatomy proves to the satisfaction of every
+unprejudiced and critical student the significant fact that the body of
+man and that of the anthropoid ape are not only peculiarly similar, but
+they are practically one and the same in every important respect. The
+same two hundred bones, in the same order and structure, make up our
+inner skeleton; the same three hundred muscles effect our movements;
+the same hair clothes our skin; the same groups of ganglionic cells
+build up the marvellous structure of our brain; the same four chambered
+heart is the central pulsometer in our circulation; the same thirty-two
+teeth are set in the same order in our jaws; the same salivary,
+hepatic, and gastric glands compass our digestive process; the same
+reproductive organs insure the maintenance of our race.
+
+It is true that we find, on close examination, certain minor
+differences in point of size and shape in most of the organs of man
+and the ape; but we discover the same, or similar, differences
+between the higher and lower races of men, when we make a careful
+comparison--even, in fact, in a minute comparison of the various
+individuals of our own race. We find no two persons who have exactly
+the same size and form of nose, ears, eyes, and so forth. One has
+only to compare attentively these special features in many different
+persons in any large company to convince one's self of the astonishing
+diversity of their construction and the infinite variability of
+specific forms. Not infrequently even two sisters are so much unlike
+as to make their origin from the same parents almost incredible. Yet
+all these individual variations do not weaken the significance of the
+fundamental similarity of structure; they are traceable to certain
+minute differences in the growth of the individual features.
+
+
+
+
+CHAPTER III
+
+OUR LIFE
+
+    Development of Physiology in Antiquity and the Middle Ages:
+    Galen--Experiment and Vivisection--Discovery of the Circulation
+    of the Blood by Harvey--Vitalism: Haller--Teleological and
+    Vitalistic Conception of Life--Mechanical and Monistic View
+    of the Physiological Processes--Comparative Physiology in the
+    Nineteenth Century: Johannes Müller--Cellular Physiology: Max
+    Verworn--Cellular Pathology: Virchow--Mammal Physiology--Similarity
+    of all Vital Activity in Man and the Ape
+
+
+It is only in the nineteenth century that our knowledge of human life
+has attained the dignity of a genuine, independent science; during the
+course of the century it has developed into one of the highest, most
+interesting, and most important branches of knowledge. This "science
+of the vital functions," physiology, had, it is true, been regarded
+at a much earlier date as a desirable, if not a necessary, condition
+of success in medical treatment, and had been constantly associated
+with anatomy, the science of the structure of the body. But it was
+only much later, and much more slowly, than the latter that it could
+be thoroughly studied, as it had to contend with much more serious
+difficulties.
+
+The idea of life, as the opposite of death, naturally became the
+subject of speculation at a very early age. In the living man, just
+as in other living animals, there were certain peculiar changes,
+especially movements, which were wanting in lifeless nature:
+spontaneous locomotion, the beat of the heart, the drawing of the
+breath, speech, and so forth. But the discrimination of such "organic
+movements" from similar phenomena in inorganic bodies was by no means
+easy, and was frequently impossible; the flowing stream, the flickering
+flame, the rushing wind, the falling rock, seemed to man to exhibit
+the same movements. It was quite natural that primitive man should
+attribute an independent life to these "dead" bodies. He knew no more
+of the real sources of movement in the one case than in the other.
+
+We find the earliest scientific observations on the nature of man's
+vital functions (as well as on his structure) in the Greek natural
+philosophers and physicians of the sixth and fifth centuries before
+Christ. The best collection of the physiological facts which were known
+at that time is to be found in the _Natural History_ of Aristotle; a
+great number of his assertions were probably taken from Democritus
+and Hippocrates. The school of the latter had already made attempts
+to explain the mystery; it postulated as the ultimate source of life
+in man and the beasts a volatile "spirit of life" (Pneuma); and
+Erasistratus (280 B.C.) already drew a distinction between the lower
+and the higher "spirit of life," the _pneuma zoticon_ in the heart and
+the _pneuma psychicon_ in the brain.
+
+The credit of gathering these scattered truths into unity, and of
+making the first attempt at a systematic physiology, belongs to the
+great Greek physician Galen; we have already recognized in him the
+first great anatomist of antiquity (cf. p. 23). In his researches
+into the organs of the body he never lost sight of the question of
+their vital activity, their functions; and even in this direction he
+proceeded by the same comparative method, taking for his principal
+study the animals which approach nearest to man. Whatever he learned
+from these he applied directly to man. He recognized the value of
+physiological experiment; in his vivisection of apes, dogs, and
+swine he made a number of interesting experiments. Vivisection has
+been made the object of a violent attack in recent years, not only
+by the ignorant and narrow-minded, but by theological enemies of
+knowledge and by perfervid sentimentalists; it is, however, one of the
+_indispensable_ methods of research into the nature of life, and has
+given us invaluable information on the most important questions. This
+was recognized by Galen seventeen hundred years ago.
+
+Galen reduces all the different functions of the body to three
+groups, which correspond to the three forms of the _pneuma_, or vital
+spirit. The _pneuma psychicon_--the soul--which resides in the brain
+and nerves, is the cause of thought, sensation, and will (voluntary
+movement); the _pneuma zoticon_--the heart--is responsible for the beat
+of the heart, the pulse, and the temperature; the _pneuma physicon_,
+seated in the liver, is the source of the so-called vegetative
+functions, digestion and assimilation, growth and reproduction.
+He especially emphasized the renewal of the blood in the lungs,
+and expressed a hope that we should some day succeed in isolating
+the permanent element in the atmosphere--the _pneuma_, as he calls
+it--which is taken into the blood in respiration. More than fifteen
+centuries elapsed before this _pneuma_--oxygen--was discovered by
+Lavoisier.
+
+In human physiology, as well as in anatomy, the great system of Galen
+was for thirteen centuries the _Codex aureus_, the inviolable source of
+all knowledge. The influence of Christianity, so fatal to scientific
+culture, raised the same insuperable obstacles in this as in every
+other branch of secular knowledge. Not a single scientist appeared
+from the third to the sixteenth century who dared to make independent
+research into man's vital activity, and transcend the limits of the
+Galenic system. It was not until the sixteenth century that experiments
+were made in that direction by a number of distinguished physicians
+and anatomists (Paracelsus, Servetus, Vesalius, and others). In 1628
+Harvey published his great discovery of the circulation of the blood,
+and showed that the heart is a pump, which drives the red stream
+unceasingly through the connected system of arteries and veins by a
+rhythmic, unconscious contraction of its muscles. Not less important
+were Harvey's researches into the procreation of animals, as a result
+of which he formulated the well-known law: "Every living thing comes
+from an egg" (_omne vivum ex ovo_).
+
+The powerful impetus which Harvey gave to physiological observation and
+experiment led to a great number of discoveries in the sixteenth and
+seventeenth centuries. These were co-ordinated for the first time by
+the learned Albrecht Haller about the middle of the last century; in
+his great work, _Elementa Physiologiae_, he established the inherent
+importance of the science, independently of its relation to practical
+medicine. In postulating, however, a special "sensitive force or
+sensibility" for neural action, and a special "irritability" for
+muscular movement, Haller gave strong support to the erroneous idea of
+a specific "vital force" (_vis vitalis_).
+
+For more than a century afterwards, from the middle of the eighteenth
+until the middle of the nineteenth century, medicine and (especially)
+physiology were dominated by the old idea that a certain number of the
+vital processes may be traced to physical and chemical causes, but that
+others are the outcome of a special vital force which is independent
+of physical agencies. However much scientists differed in their
+conceptions of its nature and its relation to the "soul," they were all
+agreed as to its independence of, and essential distinction from, the
+chemico-physical forces of ordinary "matter"; it was a self-contained
+force (_archaeus_), unknown in inorganic nature, which compelled
+ordinary forces into its service. Not only the distinctly psychical
+activity, the sensibility of the nerves and the irritability of the
+muscles, but even the phenomena of sense activity, of reproduction,
+and of development seemed so wonderful and so mysterious in their
+sources that it was impossible to attribute them to simple physical
+and chemical processes. As the free activity of the vital force
+was purposive and conscious, it led, in philosophy, to a complete
+_teleology_; especially did this seem indisputable when even the
+"critical" philosopher Kant had acknowledged, in his famous critique
+of the teleological position, that, though the mind's authority to
+give a mechanical interpretation of all phenomena is theoretically
+unlimited, yet its actual capacity for such interpretation does not
+extend to the phenomena of organic life; here we are compelled to have
+recourse to a _purposive_--therefore _supernatural_--principle. This
+divergence of the _vital_ phenomena from the _mechanical_ processes of
+life became, naturally, more conspicuous as science advanced in the
+chemical and physical explanation of the latter. The circulation of the
+blood and a number of other phenomena could be traced to mechanical
+agencies; respiration and digestion were attributable to chemical
+processes like those we find in inorganic nature. On the other hand,
+it seemed impossible to do this with the wonderful performances of the
+nerves and muscles, and with the characteristic life of the mind; the
+co-ordination of all the different forces in the life of the individual
+seemed also beyond such a mechanical interpretation. Hence there arose
+a complete physiological dualism--an essential distinction was drawn
+between inorganic and organic nature, between mechanical and vital
+processes, between material force and life force, between the body and
+the soul. At the beginning of the nineteenth century this vitalism was
+firmly established in France by Louis Dumas, and in Germany by Reil.
+Alexander Humboldt had already published a poetical presentation of it
+in 1795, in his narrative of the _Legend of Rhodes_; it is repeated,
+with critical notes, in his _Views of Nature_.
+
+In the first half of the seventeenth century the famous philosopher
+Descartes, starting from Harvey's discovery of the circulation of the
+blood, put forward the idea that the body of man, like that of other
+animals, is merely an intricate machine, and that its movements take
+place under the same mechanical laws as the movements of an automaton
+of human construction. It is true that Descartes, at the same time,
+claimed for man the exclusive possession of a perfectly independent,
+immaterial soul, and held that its subjective experience, thought,
+was the only thing in the world of which we have direct and certain
+cognizance ("_Cogito, ergo sum_"). Yet this dualism did not prevent
+him from doing much to advance our knowledge of the mechanical life
+processes in detail. Borelli followed (1660) with a reduction of the
+movements of the animal body to purely physical laws, and Sylvius
+endeavored, about the same time, to give a purely chemical explanation
+of the phenomena of digestion and respiration; the former founded the
+_iatromechanical_, the latter the _iatrochemical_, school of medicine.
+However, these rational tendencies towards a natural, mechanical
+explanation of the phenomena of life did not attain to a universal
+acceptance and application; in the course of the eighteenth century
+they fell entirely away before the advance of teleological vitalism.
+The final disproof of the latter and a return to mechanism only became
+possible with the happy growth of the new science of comparative
+physiology in the forties of the present century.
+
+Our knowledge of the vital functions, like our knowledge of the
+structure of the human body, was originally obtained, for the most
+part, not by direct observation of the human organism itself, but by
+a study of the more closely related animals among the vertebrates,
+especially the mammals. In this sense the very earliest beginning
+of human anatomy and physiology was "comparative." But the distinct
+science of "comparative physiology," which embraces the whole sphere
+of life phenomena, from the lowest animal up to man, is a triumph of
+the nineteenth century. Its famous creator was Johannes Müller, of
+Berlin (born, the son of a shoemaker, at Coblentz, in 1801). For fully
+twenty-five years--from 1833 to 1858--this most versatile and most
+comprehensive biologist of our age evinced an activity at the Berlin
+University, as professor and investigator, which is only comparable
+with the associated work of Haller and Cuvier. Nearly every one of the
+great biologists who have taught and worked in Germany for the last
+sixty years was, directly or indirectly, a pupil of Johannes Müller.
+Starting from the anatomy and physiology of man, he soon gathered all
+the chief groups of the higher and lower animals within his sphere
+of comparison. As, moreover, he compared the structure of extinct
+animals with the living, and the healthy organism with the diseased,
+endeavoring to bring together all the phenomena of life in a truly
+philosophic fashion, he attained a biological knowledge far in advance
+of his predecessors.
+
+The most valuable fruit of these comprehensive studies of Johannes
+Müller was his _Manual of Human Physiology_. This classical work
+contains much more than the title indicates; it is the sketch of
+a comprehensive "comparative biology." It is still unsurpassed in
+respect of its contents and range of investigation. In particular,
+we find the methods of observation and experiment applied in it as
+masterfully as the philosophic processes of induction and deduction.
+Müller was originally a vitalist, like all the physiologists of his
+time. Nevertheless, the current idea of a vital force took a novel
+form in his speculations, and gradually transformed itself into the
+very opposite. For he attempted to explain the phenomena of life
+mechanically in every department of physiology. His "transfigured"
+vital force was not _above_ the physical and chemical laws of the rest
+of nature but entirely bound up with them. It was, in a word, nothing
+more than life itself--that is, the sum of all the movements which we
+perceive in the living organism. He sought especially to give them
+the same mechanical interpretation in the life of the senses and of
+the mind as in the working of the muscles; the same in the phenomena
+of circulation, respiration, and digestion as in generation and
+development. Müller's success was chiefly due to the fact that he
+always began with the simplest life phenomena of the lowest animals,
+and followed them step by step in their gradual development up to the
+very highest, to man. In this his method of _critical comparison_
+proved its value both from the physiological and from the anatomical
+point of view. Johannes Müller is, moreover, the only great scientist
+who has equally cultivated these two branches of research, and combined
+them with equal brilliancy. Immediately after his death his vast
+scientific kingdom fell into four distinct provinces, which are now
+nearly always represented by four or more chairs--human and comparative
+anatomy, pathological anatomy, physiology, and the history of
+evolution. This sudden division of Müller's immense realm of learning
+in 1858 has been compared to the dissolution of the empire which
+Alexander the Great had consolidated and ruled.
+
+Among the many pupils of Johannes Müller who, either during his
+lifetime or after his death, labored hard for the advancement of the
+various branches of biology, one of the most fortunate--if not the
+most important--was Theodor Schwann. When the able botanist Schleiden,
+in 1838, indicated the cell as the common elementary organ of all
+plants, and proved that all the different tissues of the plant are
+merely combinations of cells, Johannes Müller recognized at once the
+extraordinary possibilities of this important discovery. He himself
+sought to point out the same composition in various tissues of the
+animal body--for instance, in the spinal cord of vertebrates--and
+thus led his pupil, Schwann, to extend the discovery to all the
+animal tissues. This difficult task was accomplished by Schwann in
+his _Microscopic Researches into the Accordance in the Structure and
+Growth of Plants and Animals_ (1839). Thus was the foundation laid
+of the "cellular theory," the profound importance of which, both in
+physiology and anatomy, has become clearer and more widely recognized
+in each subsequent year. Moreover, it was shown by two other pupils
+of Johannes Müller that the activity of all organisms is, in the
+ultimate analysis, the activity of the components of their tissues, the
+microscopic cells--these were the able physiologist Ernst Brücke, of
+Vienna, and the distinguished histologist Albert Kölliker, of Würzburg.
+Brücke correctly denominated the cells the "elementary organisms," and
+showed that, in the body of man and of all other animals, they are the
+only actual, independent factors of the life process. Kölliker earned
+special distinction, not only in the construction of the whole science
+of histology, but particularly by showing that the animal ovum and its
+products are simple cells.
+
+Still, however widely the immense importance of the cellular theory for
+all biological research was acknowledged, the "cellular physiology"
+which is based on it only began an independent development very
+recently. In this Max Verworn (of Jena) earned a twofold distinction.
+In his _Psycho-physiological Studies of the Protistae_ (1889) he
+showed, as a result of an ingenious series of experimental researches,
+that the "theory of a cell-soul" which I put forward in 1866[11]
+is completely established by an accurate study of the unicellular
+protozoa, and that "the psychic phenomena of the protistæ form the
+bridge which unites the chemical processes of inorganic nature with
+the mental life of the highest animals." Verworn has further developed
+these views, and based them on the modern theory of evolution, in
+his _General Physiology_. This distinguished work returns to the
+comprehensive point of view of Johannes Müller, in opposition to the
+one-sided and narrow methods of those modern physiologists who think
+to discover the nature of the vital phenomena by the exclusive aid of
+chemical and physical experiments. Verworn showed that it is only by
+Müller's comparative method and by a profound study of the physiology
+of the cell that we can reach the higher stand-point which will give us
+a comprehensive survey of the wonderful realm of the phenomena of life.
+Only thus do we become convinced that the vital processes in man are
+subject to the same physical and chemical laws as those of all other
+animals.
+
+The fundamental importance of the cellular theory for all branches of
+biology was made clear in the second half of the nineteenth century,
+not only by the rapid progress of morphology and physiology, but also
+by the entire reform of that biological science which has always
+been deemed most important on account of its relation to practical
+medicine--pathology, or the science of disease. Many even of the
+older physicians were convinced that human diseases were natural
+phenomena, like all other manifestations of life, and should be studied
+scientifically, like other vital functions. Particular schools of
+medicine--the Iatrophysical and the Iatrochemical--had already, in
+the seventeenth century, attempted to trace the sources of disease to
+certain physical and chemical changes. However, the imperfect condition
+of science at that period precluded any lasting results of these
+efforts. Many of the older theories, which sought the nature of disease
+in supernatural and mystical causes, were almost universally accepted
+down to the middle of the nineteenth century.
+
+It was then that Rudolf Virchow, another pupil of Müller, conceived
+the happy idea of transferring the cellular theory from the healthy to
+the diseased organism; he sought in the more minute metamorphoses of
+the diseased cells and the tissues they composed the true source of
+those larger changes which, in the form of disease, threaten the living
+organism with peril and death. Especially during the seven years of
+his professorship at Würzburg (1849-56) Virchow pursued his great task
+with such brilliant results that his _Cellular Pathology_ (published in
+1858) turned, at one stroke, the whole of pathology and the dependent
+science of practical medicine into new and eminently fruitful paths.
+This reform of medicine is significant for our present purpose in that
+it led us to a monistic and purely scientific conception of disease. In
+sickness, no less than in health, man is subject to the same eternal
+"iron laws" of physics and chemistry as all the rest of the organic
+world.
+
+Among the numerous classes of animals which modern zoology
+distinguishes the mammals occupy a pre-eminent position, not only on
+morphological grounds, but also for physiological reasons. As man
+belongs to the class of mammals (see p. 27) by every portion of his
+frame, we must expect him to share his characteristic functions with
+the rest of the mammals. Such we find to be the case. The circulation
+of the blood and respiration are accomplished in man under precisely
+the same laws and in the same manner as in all the other mammals--_and
+in these alone_; they are determined by the peculiar structure of
+their heart and lungs. In mammals only is all the arterial blood
+conducted from the left ventricle of the heart to the body by one,
+the _left_, branch of the aorta, while in birds it passes along the
+_right_ branch, and in reptiles along both branches. The blood of
+mammals is distinguished from that of any other vertebrate by the
+circumstance that its red cells have lost their nucleus (by reversion).
+The respiratory movements are effected largely by the diaphragm in
+this class of animals alone, because only in them does it form a
+complete partition between the pectoral and abdominal cavities. Special
+importance, however, in this highest class of animals, attaches to
+the production of milk in the breasts (_mammae_), and to the peculiar
+method of the rearing of the young, which entails the supplying of the
+offspring with the mother's milk. As this nutritive process reacts most
+powerfully on the other vital functions, and the maternal affection of
+mammals must have arisen from this intimate form of rearing, the name
+of the class justly reminds us of its great importance. In millions of
+pictures, most of them produced by painters of the highest rank, the
+"madonna with the child" is revered as the purest and noblest type of
+maternal love--the instinct which is found in its extreme form in the
+exaggerated tenderness of the mother-ape.
+
+As the apes approach nearest to man of all the mammals in point of
+structure, we shall expect to hear the same of their vital functions;
+and that we find to be the case. Everybody knows how closely the
+habits, the movements, the sense activity, the mental life, and the
+parental customs of apes resemble those of man. Scientific physiology
+proves the same significant resemblance in other less familiar
+processes, particularly in the working of the heart, the division
+of the breasts, and the sexual life. In the latter connection it is
+especially noteworthy that the mature females of many kinds of apes
+suffer a periodical discharge of blood from the womb, which corresponds
+to the menstruation of the human female. The secretion of the milk in
+the glands and the suctorial process also take place in the female ape
+in precisely the same fashion as in women.
+
+Finally, it is of especial interest that the speech of apes seems on
+physiological comparison to be a stage in the formation of articulate
+human speech. Among living apes there is an Indian species which is
+musical; the _hylobates syndactylus_ sings a full octave in perfectly
+pure, harmonious half-tones. No impartial philologist can hesitate any
+longer to admit that our elaborate rational language has been slowly
+and gradually developed out of the imperfect speech of our Pliocene
+simian ancestors.
+
+
+
+
+CHAPTER IV
+
+OUR EMBRYONIC DEVELOPMENT
+
+    The Older Embryology--The Theory of Preformation--The Theory of
+    Scatulation: Haller and Leibnitz--The Theory of Epigenesis: C. F.
+    Wolff--The Theory of Germinal Layers: Carl Ernst Baer--Discovery
+    of the Human Ovum: Remak, Kölliker--The Egg-Cell and the
+    Sperm-Cell--The Theory of the Gastræa--Protozoa and Metazoa--The
+    Ova and the Spermatozoa: Oscar Hertwig--Conception--Embryonic
+    Development in Man--Uniformity of the Vertebrate Embryo--The
+    Germinal Membranes in Man--The Amnion, the Serolemma, and the
+    Allantois--The Formation of the Placenta and the "After-Birth"--The
+    _Decidua_ and the _Funiculus Umbilicalis_--The Discoid Placenta of
+    Man and the Ape
+
+
+Comparative ontogeny, or the science of the development of the
+individual animal, is a child of the nineteenth century in even a truer
+sense than comparative anatomy and physiology. How is the child formed
+in the mother's womb? How do animals evolve from ova? How does the
+plant come forth from the seed? These pregnant questions have occupied
+the thoughtful mind for thousands of years. Yet it is only seventy
+years since the embryologist Baer pointed out the correct means and
+methods for penetrating into the mysteries of embryonic life; it is
+only forty years since Darwin, by his reform of the theory of descent,
+gave us the key which should open the long-closed door, and lead to
+a knowledge of embryonic agencies. As I have endeavored to give a
+complete, popular presentation of this very interesting but difficult
+study in the first section of my _Anthropogeny_, I will confine myself
+here to a brief survey and discussion of the most important phenomena.
+Let us first cast a historical glance at the older ontogeny, and the
+theory of preformation which is connected with it.
+
+The classical works of Aristotle, the many-sided "father of science,"
+are the oldest known scientific sources of embryology, as we found them
+to be for comparative anatomy. Not only in his great natural history,
+but also in a special small work, _Five Books on the Generation and
+Development of Animals_, the great philosopher gives us a host of
+interesting facts, adding many observations on their significance; it
+was not until our own days that many of them were fully appreciated,
+and, indeed, we may say, discovered afresh. Naturally, many fables and
+errors are mixed up with them; it was all that was known at that time
+of the hidden growth of the human germ. Yet during the long space of
+the next two thousand years the slumbering science made no further
+progress. It was not until the commencement of the seventeenth century
+that there was a renewal of activity. In 1600 the Italian anatomist
+Fabricius ab Aquapendente published at Padua the first pictures and
+descriptions of the embryos of man and some of the higher animals; in
+1687 the famous Marcello Malpighi, of Bologna, a distinguished pioneer
+alike in zoology and botany, published the first consistent exposition
+of the growth of the chick in the hatched egg.
+
+All these older scientists were possessed with the idea that the
+complete body, with all its parts, was already contained in the ovum
+of animals, only it was so minute and transparent that it could not
+be detected; that, therefore, the whole development was nothing more
+than a _growth_, or an "unfolding," of the parts that were already
+"infolded" (_involutae_). This erroneous notion, almost universally
+accepted until the beginning of the present century, is called the
+"preformation theory"; sometimes it is called the "evolution theory"
+(in the literal sense of "unfolding"); but the latter title is accepted
+by modern scientists for the very different theory of "transformation."
+
+Closely connected with the preformation theory, and as a logical
+consequence of it, there arose in the last century a further theory
+which keenly interested all thoughtful biologists--the curious
+"theory of scatulation." As it was thought that the outline of the
+entire organism, with all its parts, was present in the egg, the
+ovary of the embryo had to be supposed to contain the ova of the
+following generation; these, again, the ova of the next, and so on
+_in infinitum_! On that basis the distinguished physiologist Haller
+calculated that God had created together, 6000 years ago--on the sixth
+day of his creatorial labors--the germs of 200,000,000,000 men, and
+ingeniously packed them all in the ovary of our venerable mother Eve.
+Even the gifted philosopher Leibnitz fully accepted this conclusion,
+and embodied it in his monadist theory; and as, on his theory, soul and
+body are in eternal, inseparable companionship, the consequence had to
+be accepted for the soul; "the souls of men have existed in organized
+bodies in their ancestors from Adam downward--that is, from the very
+beginning of things."
+
+In the month of November, 1759, a young doctor of twenty-six years,
+Caspar Friedrich Wolff (son of a Berlin tailor), published his
+dissertation for the degree at Halle, under the title, _Theoria
+Generationis_. Supported by a series of most laborious and painstaking
+observations, he proved the entire falsity of the dominant theories of
+preformation and scatulation. In the hatched egg there is at first no
+trace of the coming chick and its organs; instead of it we find on top
+of the yolk a small, circular, white disk. This thin "germinal disk"
+becomes gradually round, and then breaks up into four folds, lying
+upon each other, which are the rudiments of the four chief systems of
+organs--the nervous system above, the muscular system underneath, the
+vascular system (with the heart), and, finally, the alimentary canal.
+Thus, as Wolff justly remarked, the embryonic development does not
+consist in an unfolding of the preformed organs, but in a series of
+new constructions; it is a true _epigenesis_. One part arises after
+another, and all make their appearance in a simple form, which is very
+different from the later structure. This only appears after a series of
+most remarkable formations. Although this great discovery--one of the
+most important of the eighteenth century--could be directly proved by a
+verification of the facts Wolff had observed, and although the "theory
+of generation" which was founded on it was in reality not a theory at
+all, but a simple fact, it met with no sympathy whatever for half a
+century. It was particularly retarded by the high authority of Haller,
+who fought it strenuously with the dogmatic assertion that "there is
+no such thing as development: no part of the animal body is formed
+before another; all were created together." Wolff, who had to go to St.
+Petersburg, was long in his grave before the forgotten facts he had
+observed were discovered afresh by Oken at Jena, in 1806.
+
+After Wolff's "epigenesis theory" had been established by Oken and
+Neckel (whose important work on the development of the alimentary
+canal was translated from Latin into German), a number of young German
+scientists devoted themselves eagerly to more accurate embryological
+research. The most important and successful of these was Carl Ernst
+Baer. His principal work appeared in 1828, with the title, _History of
+the Development of Animals: Observations and Reflections_. Not only
+the phenomena of the formation of the germ are clearly illustrated
+and fully described in it, but it adds a number of very pregnant
+speculations. In particular, the form of the embryo of man and the
+mammals is correctly presented, and the vastly different development
+of the lower invertebrate animals is also considered. The two leaflike
+layers which appear in the round germ disk of the higher vertebrates
+first divide, according to Baer, into two further layers, and these
+four germinal layers are transformed into four tubes, which represent
+the fundamental organs--the skin layer, the muscular layer, the
+vascular layer, and the mucous layer. Then, by very complicated
+evolutionary processes, the later organs arise, in substantially the
+same manner, in man and all the other vertebrates. The three chief
+groups of invertebrates, which in their turn differ widely from each
+other, have a very different development.
+
+One of the most important of Baer's many discoveries was the finding of
+the human ovum. Up to that time the little vesicles which are found in
+great numbers in the human ovary and in that of all other mammals had
+been taken for the ova. Baer was the first to prove, in 1827, that the
+real ova are enclosed in these vesicles--the "Graafian follicles"--and
+much smaller, being tiny spheres 1-120th inch in diameter, visible
+to the naked eye as minute specks under favorable conditions. He
+discovered likewise that from this tiny ovum of the mammal there
+develops first a characteristic germ globule, a hollow sphere with
+liquid contents, the wall of which forms the slender germinal membrane,
+or blastoderm.
+
+Ten years after Baer had given a firm foundation to embryological
+science by his theory of germ layers a new task confronted it on the
+establishment of the cellular theory in 1838. What is the relation of
+the ovum and the layers which arise from it to the tissues and cells
+which compose the fully developed organism? The correct answer to this
+difficult question was given about the middle of this century by two
+distinguished pupils of Johannes Müller--Robert Remak, of Berlin, and
+Albert Kölliker, of Würzburg. They showed that the ovum is at first one
+simple cell, and that the many germinal globules, or granules, which
+arise from it by repeated segmentation, are also simple cells. From
+this mulberry-like group of cells are constructed first the germinal
+layers, and subsequently by differentiation, or division of labor,
+all the different organs. Kölliker has the further merit of showing
+that the seminal fluid of male animals is also a mass of microscopic
+cells. The active pin-shaped "seed-animalcules," or _spermatozoa_, in
+it are merely ciliated cells, as I first proved in the case of the
+seed-filaments of the sponge in 1866. Thus it was proved that both
+the materials of generation, the male sperm and the female ova, fell
+in with the cellular theory. That was a discovery of which the great
+philosophic significance was not appreciated until a much later date,
+on a close study of the phenomena of conception in 1875.
+
+All the older studies in embryonic development concern man and the
+higher vertebrates, especially the embryonic bird, since hens' eggs
+are the largest and most convenient objects for investigation, and
+are plentiful enough to facilitate experiment; we can hatch them in
+the incubator, as well as by the natural function of the hen, and
+so observe from hour to hour, during the space of three weeks, the
+whole series of formations, from the simple germ cell to the complete
+organism. Even Baer had only been able to gather from such observations
+the fact that the different classes of vertebrates agreed in the
+characteristic form of the germ layers and the growth of particular
+organs. In the innumerable classes of invertebrates, on the other
+hand--that is, in the great majority of animals--the embryonic
+development seemed to run quite a different course, and most of them
+seemed to be altogether without true germinal layers. It was not until
+about the middle of the century that such layers were found in some of
+the invertebrates. Huxley, for instance, found them in the medusæ in
+1849, and Kölliker in the cephalopods in 1844. Particularly important
+was the discovery of Kowalewsky (1886) that the lowest vertebrate--the
+lancelot, or amphioxus--is developed in just the same manner (and a
+very original fashion it is) as an invertebrate, apparently quite
+remote, tunicate, the sea-squirt, or ascidian. Even in some of the
+worms, the radiata and the articulata, a similar formation of the
+germinal layers was pointed out by the same observer. I myself was
+then (since 1886) occupied with the embryology of the sponges, corals,
+medusæ, and siphonophoræ, and, as I found the same formation of two
+primary germ layers everywhere in these lowest classes of multicellular
+animals, I came to the conclusion that this important embryonic
+feature is common to the entire animal world. The circumstance that
+in the sponges and the cnidaria (polyps, medusæ, etc.) the body
+consists for a long time, sometimes throughout life, merely of two
+simple layers of cells, seemed to me especially significant. Huxley
+had already (1849) compared these, in the case of the medusæ, with the
+two primary germinal layers of the vertebrates. On the ground of these
+observations and comparisons I then, in 1872, in my _Philosophy of the
+Calcispongiae_, published the "theory of the gastræa," of which the
+following are the essential points:
+
+I. The whole animal world falls into two essentially different groups,
+the unicellular primitive animals (Protozoa) and the multicellular
+animals with complex tissues (Metazoa). The entire organism of the
+protozoon (the rhizopods of the infusoria) remains throughout life a
+single simple cell (or occasionally a loose colony of cells without
+the formation of tissue, a _coenobium_). The organism of the metazoon,
+on the contrary, is only unicellular at the commencement, and is
+subsequently built up of a number of cells which form tissues.
+
+II. Hence the method of reproduction and development is very different
+in each of these great categories of animals. The protozoa usually
+multiply by _non-sexual_ means, by fission, gemmation, or spores;
+they have no real ova and no sperm. The metazoa, on the contrary, are
+divided into male and female sexes, and generally propagate sexually,
+by means of true ova, which are fertilized by the male sperm.
+
+III. Hence, further, true germinal layers, and the tissues which are
+formed from them, are found only in the metazoa; they are entirely
+wanting in the protozoa.
+
+IV. In all the metazoa only two primary layers appear at first, and
+these have always the same essential significance; from the _outer_
+layer the external skin and the nervous system are developed; from the
+_inner_ layer are formed the alimentary canal and all the other organs.
+
+V. I called the germ, which always arises first from the impregnated
+ovum, and which consists of these two primary layers, the "gut-larva,"
+or the _gastrula_; its cup-shaped body with the two layers encloses
+originally a simple digestive cavity, the primitive gut (the
+_progaster_ or _archenteron_), and its simple opening is the primitive
+mouth (the _prostoma_ or _blastoporus_). These are the earliest organs
+of the multicellular body, and the two cell layers of its enclosing
+wall, simple epithelia, are its earliest tissues; all the other organs
+and tissues are a later and secondary growth from these.
+
+VI. From this similarity, or _homology_, of the gastrula in all classes
+of compound animals I drew the conclusion, in virtue of the biogenetic
+law (p. 81), that all the metazoa come originally from one simple
+ancestral form, the _gastraea_, and that this ancient (Laurentian),
+long-extinct form had the structure and composition of the actual
+gastrula, in which it is preserved by heredity.
+
+VII. This phylogenetic conclusion, based on the comparison of
+ontogenetic facts, is confirmed by the circumstance that there are
+several of these gastræades still in existence (_gastraemaria_,
+_cyemaria_, _physemaria_, etc.), and also some ancient forms of
+other animal groups whose organization is very little higher (the
+_olynthus_ of the sponges, the _hydra_, or common fresh-water polyp,
+of the cnidaria, the _convoluta_ and other cryptocæla, or worms of the
+simplest type, of the _platodes_).
+
+VIII. In the further development of the various tissue-forming animals
+from the gastrula we have to distinguish two principal groups. The
+earlier and _lower_ types (the _coelenteria_ or _acoelomia_) have
+no body cavity, no vent, and no blood; such is the case with the
+gastræades, sponges, cnidaria, and platodes. The later and _higher_
+types (the _caelomaria_ or _bilateria_), on the other hand, have a
+true body cavity, and generally blood and a vent; to these we must
+refer the worms and the higher types of animals which were evolved from
+these later on, the echinodermata, mollusca, articulata, tunicata, and
+vertebrata.
+
+Those are the main points of my "gastræa theory"; I have since
+enlarged the first sketch of it (given in 1872), and have endeavored
+to substantiate it in a series of "Studies on the gastræa theory"
+(1873-84). Although it was almost universally rejected at first, and
+fiercely combated for ten years by many authorities, it is now (and has
+been for the last fifteen years) accepted by nearly all my colleagues.
+Let us now see what far-reaching consequences follow from it, and
+from the evolution of the germ, especially with regard to our great
+question, "the place of man in nature."
+
+The human ovum, like that of all other animals, is a single cell, and
+this tiny globular egg cell (about the 120th of an inch in diameter)
+has just the same characteristic appearance as that of all other
+viviparous organisms. The little ball of protoplasm is surrounded
+by a thick, transparent, finely reticulated membrane, called the
+_zona pellucida_; even the little, globular, germinal vesicle (the
+cell-nucleus), which is enclosed in the protoplasm (the cell-body),
+is of the same size and the same qualities as in the rest of the
+mammals. The same applies to the active spermatozoa of the male,
+the minute, threadlike, ciliated cells of which millions are found
+in every drop of the seminal fluid; on account of their lifelike
+movements they were previously taken to be forms of life, as the name
+indicates (spermatozoa--sperm animals). Moreover, the origin of both
+these important sexual cells in their respective organs is the same in
+man as in the other mammals; both the ova in the ovary of the female
+and the spermatozoa in the spermarium of the male arise in the same
+fashion--they always come from cells, which are originally derived from
+the coelous epithelium, the layer of cells which clothes the cavity
+of the body.
+
+The most important moment in the life of every man, as in that of all
+other complex animals, is the moment in which he begins his individual
+existence; it is the moment when the sexual cells of both parents meet
+and coalesce for the formation of a single simple cell. This new cell,
+the impregnated egg cell, is the individual stem cell (the _cytula_),
+the continued segmentation of which produces the cells of the germinal
+layers and the gastrula. With the formation of this cytula, hence in
+the process of conception itself, the existence of the personality, the
+independent individual, commences. This ontogenic fact is supremely
+important, for the most far-reaching conclusions may be drawn from
+it. In the first place, we have a clear perception that man, like all
+the other complex animals, inherits all his personal characteristics,
+bodily and mental, from his parents; and, further, we come to the
+momentous conclusion that the new personality which arises thus can lay
+no claim to "immortality."
+
+Hence the minute processes of conception and sexual generation are
+of the first importance. We are, however, only familiar with their
+details since 1875, when Oscar Hertwig, my pupil and fellow-traveller
+at that time, began his researches into the impregnation of the egg
+of the sea-urchin at Ajaccio, in Corsica. The beautiful capital of
+the island in which Napoleon the Great was born, in 1769, was also
+the spot in which the mysteries of animal conception were carefully
+studied for the first time in their most important aspects. Hertwig
+found that the one essential element in conception is the coalescence
+of the two sexual cells and their nuclei. Only one out of the millions
+of male ciliated cells which press round the ovum penetrates to its
+nucleus. The nuclei of both cells, of the spermatozoon and of the ovum,
+drawn together by a mysterious force, which we take to be a chemical
+sense-activity, related to smell, approach each other and melt into
+one. Thus, by the sensitive perception of the sexual nuclei, following
+upon a kind of "erotic chemicotropism," a new cell is formed, which
+unites in itself the inherited qualities of both parents; the nucleus
+of the spermatozoon conveys the paternal features, the nucleus of the
+ovum those of the mother, to the stem cell, from which the child is
+to be developed. That applies both to the bodily and to the mental
+characteristics.
+
+The formation of the germinal layers by the repeated division of
+the stem cell, the growth of the gastrula and of the later germ
+structures which succeed it, take place in man in just the same manner
+as in the other higher mammals, under the peculiar conditions which
+differentiate this group from the lower vertebrates. In the earlier
+stages of development these special characters of the placentalia are
+not to be detected. The significant embryonic or larval form of the
+chordula, which succeeds the gastrula, has substantially the same
+structure in all vertebrates; a simple straight rod, the dorsal cord,
+lies lengthways along the main axis of the shield-shaped body--the
+"embryonic shield"; above the cord the spinal marrow develops out
+of the outer germinal layer, while the gut makes its appearance
+underneath. Then, on both sides, to the right and left of the axial
+rod, appear the segments of the "pro-vertebræ" and the outlines of
+the muscular plates, with which the formation of the members of the
+vertebrate body begins. The gill-clefts appear on either side of the
+fore-gut; they are the openings of the gullet, through which, in our
+primitive fish-ancestors, the water which had entered at the mouth
+for breathing purposes made its exit at the sides of the head. By a
+tenacious heredity these gill-clefts, which have no meaning except for
+our fish-like aquatic ancestors, are still preserved in the embryo of
+man and all the other vertebrates. They disappear after a time. Even
+after the five vesicles of the embryonic brain appear in the head,
+and the rudiments of the eyes and ears at the sides, and after the
+legs sprout out at the base of the fish-like embryo, in the form of
+two roundish, flat buds, the foetus is still so like that of other
+vertebrates that it is indistinguishable from them.
+
+The substantial similarity in outer form and inner structure which
+characterizes the embryo of man and other vertebrates in this early
+stage of development is an embryological fact of the first importance;
+from it, by the fundamental law of biogeny, we may draw the most
+momentous conclusions. There is but one explanation of it--heredity
+from a common parent form. When we see that, at a certain stage,
+the embryos of man and the ape, the dog and the rabbit, the pig and
+the sheep, although recognizable as higher vertebrates, cannot be
+distinguished from each other, the fact can only be elucidated by
+assuming a common parentage. And this explanation is strengthened when
+we follow the subsequent divergence of these embryonic forms. The
+nearer two animals are in their bodily structure, and, therefore, in
+the scheme of nature, so much the longer do we find their embryos to
+retain this resemblance, and so much the closer do they approach each
+other in the ancestral tree of their respective group, so much the
+closer is their genetic relationship. Hence it is that the embryos of
+man and the anthropoid ape retain the resemblance much later, at an
+advanced stage of development, when their distinction from the embryos
+of other mammals can be seen at a glance. I have illustrated this
+significant fact by a juxtaposition of corresponding stages in the
+development of a number of different vertebrates in my _Natural History
+of Creation_ and in my _Anthropogeny_.
+
+The great phylogenetic significance of the resemblance we have
+described is seen, not only in the comparison of the embryos of
+vertebrates, but also in the comparison of their protective membranes.
+All vertebrates of the three higher classes--reptiles, birds, and
+mammals--are distinguished from the lower classes by the possession
+of certain special foetal membranes, the amnion and the serolemma.
+The embryo is enclosed in these membranes, or bags, which are full of
+water, and is thus protected from pressure or shock. This provident
+arrangement probably arose during the Permian period, when the oldest
+reptiles, the _proreptilia_, the common ancestors of all the amniotes
+(animals with an _amnion_), completely adapted themselves to a life on
+land. Their direct ancestors, the amphibia, and the fishes are devoid
+of these foetal membranes; they would have been superfluous to these
+inhabitants of the water. With the inheritance of these protective
+coverings are closely connected two other changes in the amniotes:
+firstly, the entire disappearance of the gills (while the gill arches
+and clefts continue to be inherited as "rudimentary organs"); secondly,
+the construction of the _allantois_. This vesicular bag, filled with
+water, grows out of the hind-gut in the embryo of all the amniotes,
+and is nothing else than an enlargement of the bladder of their
+amphibious ancestors. From its innermost and inferior section is formed
+subsequently the permanent bladder of the amniotes, while the larger
+outer part shrivels up. Usually this has an important part to play for
+a long time as the respiratory organ of the embryo, a number of large
+blood-vessels spreading out over its inner surface. The formation of
+the membranes, the amnion and the serolemma, and of the allantois,
+is just the same, and is effected by the same complicated process of
+growth, in man as in all the other amniotes; _man is a true amniote_.
+
+The nourishment of the foetus in the maternal womb is effected, as
+is well known, by a peculiar organ, richly supplied with blood at its
+surface, called the _placenta_. This important nutritive organ is a
+spongy, round disk, from six to eight inches in diameter, about an
+inch thick, and one or two pounds in weight; it is separated after
+the birth of the child, and issues as the "after-birth." The placenta
+consists of two very different parts, the foetal and the maternal
+part. The latter contains highly developed sinuses, which retain the
+blood conveyed to them by the arteries of the mother. On the other
+hand, the foetal placenta is formed by innumerable branching tufts or
+villi, which grow out of the outer surface of the allantois, and derive
+their blood from the umbilical vessels. The hollow, blood-filled villi
+of the foetal placenta protrude into the sinuses of the maternal
+placenta, and the slender membrane between the two is so attenuated
+that it offers no impediment to the direct interchange of material
+through the nutritive blood-stream (by osmosis).
+
+In the older and lower groups of the placentals the entire surface
+of the chorion is covered with a number of short villi; these
+"chorion-villi" take the form of pit-like depressions of the mucous
+membrane of the mother, and are easily detached at birth. That
+happens in most of the ungulata (the sow, camel, mare, etc.), the
+cetacea, and the prosimiæ; these "mallo-placentalia" (with a _diffuse_
+placenta) have been denominated the _indeciduata_. The same formation
+is present in man and the other placentals in the beginning. It is
+soon modified, however, as the villi on one part of the chorion are
+withdrawn; while on the other part they grow proportionately stronger,
+and unite intimately with the mucous membrane of the womb. It is in
+consequence of this intimate blending that a portion of the uterus is
+detached at birth, and carried away with loss of blood. This detachable
+membrane--the _decidua_--is a characteristic of the higher placentalia,
+which have, consequently, been grouped under the title of _deciduata_;
+to that category belong the carnassia, rodentia, simiæ, and man. In
+the carnassia and some of the ungulata (the elephant, for instance)
+the placenta takes the form of a girdle, hence they are known as the
+_zonoplacentalia_; in the rodentia, the insectivora (the mole and the
+hedge-hog), the apes, and man, it takes the form of a disk.
+
+Even ten years ago the majority of embryologists thought that man
+was distinguished by certain peculiarities in the form of the
+placenta--namely, by the possession of what is called the _decidua
+reflexa_, and by a special formation of the umbilical chord which
+unites the _decidua_ to the foetus. It was supposed that the rest
+of the placentals, including the apes, were without these special
+embryonic structures. The _funiculus umbilicalis_ is a smooth,
+cylindrical cord, from sixteen to twenty-three inches long, and as
+thick as the little finger. It forms the connecting link between the
+foetus and the maternal placenta, since it conducts the nutritive
+vessels from the body of the foetus to the placenta; it comprises,
+besides, the pedicle of the allantois and the yelk-sac. The yelk-sac in
+the human case forms the greater portion of the germinal vesicle during
+the third week of gestation; but it shrivels up afterwards so that it
+was formerly entirely missed in the mature foetus. Yet it remains all
+the time in a rudimentary condition, and may be detected even after
+birth as the little umbilical vesicle. Moreover, even the vesicular
+structure of the allantois disappears at an early stage in the human
+case; with a deflection of the amnion, it gives rise to the pedicle.
+We cannot enter here into a discussion of the complicated anatomical
+and embryological relations of these structures. I have described and
+illustrated them in my _Anthropogeny_ (twenty-third chapter).
+
+The opponents of evolution still appealed to these "special features"
+of human embryology, which were supposed to distinguish man from all
+the other mammals, even so late as ten years ago. But in 1890 Emil
+Selenka proved that the same features are found in the anthropoid apes,
+especially in the orang (_satyrus_), while the lower apes are without
+them. Thus Huxley's pithecometra thesis was substantiated once more:
+"The differences between man and the great apes are not so great as
+are those between the manlike apes and the lower monkeys." The supposed
+"evidences _against_ the near blood-relationship of man and the apes"
+proved, on a closer examination of the real circumstances, to be strong
+reasons in favor of it.
+
+Every scientist who penetrates with open eyes into this dark but
+profoundly interesting labyrinth of our embryonic development, and who
+is competent to compare it critically with that of the rest of the
+mammals, will find in it a most important aid towards the elucidation
+of the descent of our species. For the various stages of our embryonic
+development, in the character of _palingenetic_ phenomena of heredity,
+cast a brilliant light on the corresponding stages of our ancestral
+tree, in accordance with the great law of biogeny. But even the
+_cenogenetic_ phenomena of adaptation, the formation of the temporary
+foetal organs--the characteristic foetal membranes, and especially
+the placenta--gives us sufficiently definite indications of our _close
+genetic relationship with the primates_.
+
+
+
+
+CHAPTER V
+
+THE HISTORY OF OUR SPECIES
+
+    Origin of Man--Mythical History of Creation--Moses and Linné--The
+    Creation of Permanent Species--The Catastrophic Theory:
+    Cuvier--Transformism: Goethe--Theory of Descent: Lamarck--Theory
+    of Selection: Darwin--Evolution (Phylogeny)--Ancestral
+    Trees--General Morphology--Natural History of Creation--Systematic
+    Phylogeny--Fundamental Law of Biogeny--Anthropogeny--Descent of Man
+    from the Ape--Pithecoid Theory--The Fossil Pithecanthropus of Dubois
+
+
+The youngest of the great branches of the living tree of biology is
+the science we call biological evolution, or _phylogeny_. It came into
+existence much later, and under much more difficult circumstances, than
+its natural sister, embryonic evolution or _ontogeny_. The object of
+the latter was to attain a knowledge of the mysterious processes by
+which the individual organism, plant or animal, developed from the egg.
+Phylogeny has to answer the much more obscure and difficult question:
+"What is the origin of the different organic species of plants and
+animals?"
+
+Ontogeny (embryology and metamorphism) could follow the empirical
+method of direct observation in the solution of its not remote problem;
+it needed but to follow, day by day and hour by hour, the visible
+changes which the foetus experiences during a brief period in the
+course of its development from the ovum. Much more difficult was
+the remote problem of phylogeny; for the slow processes of gradual
+construction, which effect the rise of new species of animals and
+plants, go on imperceptibly during thousands and even millions of
+years. Their direct observation is possible only within very narrow
+limits; the vast majority of these historical processes can only be
+known by direct inference--by critical reflection, and by a comparative
+use of empirical sciences which belong to very different fields of
+thought, palæontology, ontogeny, and morphology. To this we must
+add the immense opposition which was everywhere made to biological
+evolution on account of the close connection between questions of
+organic creation and supernatural myths and religious dogmas. For these
+reasons it can easily be understood how it is that the scientific
+existence of a true theory of origins was only secured, amid fierce
+controversy, in the course of the last forty years.
+
+Every serious attempt that was made before the beginning of the
+nineteenth century to solve the problem of the origin of species
+lost its way in the mythological labyrinth of the supernatural
+stories of creation. The efforts of a few distinguished thinkers to
+emancipate themselves from this tyranny and attain to a naturalistic
+interpretation proved unavailing. A great variety of creation myths
+arose in connection with their religion in all the ancient civilized
+nations. During the Middle Ages triumphant Christendom naturally
+arrogated to itself the sole right of pronouncing on the question; and,
+the Bible being the basis of the structure of the Christian religion,
+the whole story of creation was taken from the book of Genesis. Even
+Carl Linné, the famous Swedish scientist, started from that basis
+when, in 1735, in his classical _Systema Naturae_, he made the first
+attempt at a systematic arrangement, nomenclature, and classification
+of the innumerable objects in nature. As the best practical aid in that
+attempt he introduced the well-known double or binary nomenclature; to
+each kind of animals and plants he gave a particular specific name,
+and added to it the wider-reaching name of the genus. A _genus_ served
+to unite the nearest related _species_; thus, for instance, Linné
+grouped under the genus "dog" (_canis_), as different species, the
+house-dog (_canis familiaris_), the jackal (_canis aureus_), the wolf
+(_canis lupus_) the fox (_canis vulpes_), etc. This binary nomenclature
+immediately proved of such great practical assistance that it was
+universally accepted, and is still always followed in zoological and
+botanical classification.
+
+But the theoretical dogma which Linné himself connected with his
+practical idea of species was fraught with the gravest peril to
+science. The first question which forced itself on the mind of the
+thoughtful scientist was the question as to the nature of the concept
+of species, its contents, and its range. And the creator of the idea
+answered this fundamental question by a naïve appeal to the dominant
+Mosaic legend of creation: "_Species tot sunt diversae, quot diversas
+formas ab initio creavit infinitum ens_"--(There are just so many
+distinct species as there were distinct types created in the beginning
+by the Infinite). This theosophic dogma cut short all attempt at a
+natural explanation of the origin of species. Linné was acquainted only
+with the plant and animal worlds that exist to-day; he had no suspicion
+of the much more numerous extinct species which had peopled the earth
+with their varying forms in the earlier period of its development.
+
+It was not until the beginning of the nineteenth century that we were
+introduced to these fossil animals by Cuvier. In his famous work on
+the fossil bones of the four-footed vertebrates he gave (1812) the
+first correct description and true interpretation of many of these
+fossil remains. He showed, too, that a series of very different animal
+populations have succeeded each other in the various stages of the
+earth's history. Since Cuvier held firmly to Linné's idea of the
+absolute permanency of species, he thought their origin could only be
+explained by the supposition that a series of great cataclysms and new
+creations had marked the history of the globe; he imagined that all
+living creatures were destroyed at the commencement of each of these
+terrestrial revolutions, and an entirely new population was created
+at its close. Although this "catastrophic theory" of Cuvier's led to
+the most absurd consequences, and was nothing more than a bald faith
+in miracles, it obtained almost universal recognition, and reigned
+triumphant until the coming of Darwin.
+
+It is easy to understand that these prevalent ideas of the absolute
+unchangeability and supernatural creation of organic species could not
+satisfy the more penetrating thinkers. We find several eminent minds
+already, in the second half of the last century, busy with the attempt
+to find a natural explanation of the "problem of creation." Pre-eminent
+among them was the great German poet and philosopher, Wolfgang Goethe,
+who, by his long and assiduous study of morphology, obtained, more than
+a hundred years ago, a clear insight into the intimate connection of
+all organic forms, and a firm conviction of a common natural origin.
+In his famed _Metamorphosis of Plants_ (1790) he derived all the
+different species of plants from one primitive type, and all their
+different organs from one primitive organ--the leaf. In his vertebral
+theory of the skull he endeavored to prove that the skulls of the
+vertebrates--including man--were all alike made up of certain groups
+of bones, arranged in a definite structure, and that these bones are
+nothing else than transformed vertebræ. It was his penetrating study
+of comparative osteology that led Goethe to a firm conviction of the
+unity of the animal organization; he had recognized that the human
+skeleton is framed on the same fundamental type as that of all other
+vertebrates--"built on a primitive plan that only deviates more or less
+to one side or other in its very constant features, and still develops
+and refashions itself daily." This remodelling, or transformation,
+is brought about, according to Goethe, by the constant interaction
+of two powerful constructive forces--a centripetal force within the
+organism, the "tendency to specification," and a centrifugal force
+without, the tendency to variation, or the "idea of metamorphosis";
+the former corresponds to what we now call heredity, the latter to
+the modern idea of adaptation. How deeply Goethe had penetrated into
+their character by these philosophic studies of the "construction and
+reconstruction of organic natures," and how far, therefore, he must be
+considered the most important precursor of Darwin and Lamarck,[12] may
+be gathered from the interesting passages from his works which I have
+collected in the fourth chapter of my _Natural History of Creation_.
+These evolutionary ideas of Goethe, however, like analogous ideas of
+Kant, Owen, Treviranus, and other philosophers of the commencement of
+the century (which we have quoted in the above work), did not amount to
+more than certain general conclusions. They had not that great lever
+which the "natural history of creation" needed for its firm foundation
+on a criticism of the dogma of fixed species; this lever was first
+supplied by Lamarck.
+
+The first thorough attempt at a scientific establishment of transformism
+was made at the beginning of the nineteenth century by the great
+French scientist Jean Lamarck, the chief opponent of his colleague,
+Cuvier, at Paris. He had already, in 1802, in his _Observations on
+Living Organisms_, expressed the new ideas as to the mutability and
+formation of species, which he thoroughly established in 1809 in the
+two volumes of his profound work, _Philosophie Zoologique_. In this
+work he first gave expression to the correct idea, in opposition to
+the prevalent dogma of fixed species, that the organic "species" is
+an _artificial abstraction_, a concept of only relative value, like
+the wider-ranging concepts of genus, family, order, and class. He
+went on to affirm that all species are changeable, and have arisen
+from older species in the course of very long periods of time. The
+common parent forms from which they have descended were originally
+very simple and lowly organisms. The first and oldest of them arose
+by abiogenesis. While the type is preserved by _heredity_ in the
+succession of generations, _adaptation_, on the other hand, effects
+a constant modification of the species by change of habits and the
+exercise of the various organs. Even our human organism has arisen in
+the same natural manner, by gradual transformation, from a group of
+pithecoid mammals. For all these phenomena--indeed, for all phenomena
+both in nature and in the mind--Lamarck takes exclusively mechanical,
+physical, and chemical activities to be the true efficient causes. His
+magnificent _Philosophie Zoologique_ contains all the elements of a
+purely monistic system of nature on the basis of evolution. I have
+fully treated these achievements of Lamarck in the fourth chapter of my
+_Anthropogeny_, and in the fourth chapter of the _Natural History of
+Creation_.
+
+Science had now to wait until this great effort to give a scientific
+foundation to the theory of evolution should shatter the dominant myth
+of a "specific creation, and open out the path of natural" development.
+In this respect Lamarck was not more successful in resisting the
+conservative authority of his great opponent, Cuvier, than was his
+colleague and sympathizer, Geoffrey St. Hilaire, twenty years later.
+The famous controversies which he had with Cuvier in the Parisian
+Academy in 1830 ended with the complete triumph of the latter. I have
+elsewhere fully described these conflicts, in which Goethe took so
+lively an interest. The great expansion which the study of biology
+experienced at that time, the abundance of interesting discoveries
+in comparative anatomy and physiology, the establishment of the
+cellular theory, and the progress of ontogeny, gave zoologists and
+botanists so overwhelming a flood of welcome material to deal with
+that the difficult and obscure question of the origin of species was
+easily forgotten for a time. People rested content with the old dogma
+of creation. Even when Charles Lyell refuted Cuvier's extraordinary
+"catastrophic theory" in his _Principles of Geology_, in 1830, and
+vindicated a natural, continuous evolution for the inorganic structure
+of our planet, his simple principle of continuity found no one to
+apply it to the inorganic world. The rudiments of a natural phylogeny
+which were buried in Lamarck's works were as completely forgotten as
+the germ of a natural ontogeny which Caspar Friedrich Wolff had given
+fifty years earlier in his _Theory of Generation_. In both cases a full
+half-century elapsed before the great idea of a natural development
+won a fitting recognition. Only when Darwin (in 1859) approached the
+solution of the problem from a different side altogether, and made
+a happy use of the rich treasures of empirical knowledge which had
+accumulated in the mean time, did men begin to think once more of
+Lamarck as his great precursor.
+
+The unparalleled success of Charles Darwin is well known. It shows him
+to-day, at the close of the century, to have been, if not the greatest,
+at least the most effective of its distinguished scientists. No other
+of the many great thinkers of our time has achieved so magnificent, so
+thorough, and so far-reaching a success with a single classical work as
+Darwin did in 1859 with his famous _Origin of Species_. It is true that
+the reform of comparative anatomy and physiology by Johannes Müller
+had inaugurated a new and fertile epoch for the whole of biology, that
+the establishment of the cellular theory by Schleiden and Schwann, the
+reform of ontogeny by Baer, and the formulation of the law of substance
+by Robert Mayer and Helmholtz were scientific facts of the first
+importance; but no one of them has had so profound an influence on the
+whole structure of human knowledge as Darwin's theory of the natural
+origin of species. For it at once gave us the solution of the mystic
+"problem of creation," the great "question of all questions"--the
+problem of the true character and origin of man himself.
+
+If we compare the two great founders of transformism, we find in
+Lamarck a preponderant inclination to _deduction_, and to forming a
+completely monistic scheme of nature; in Darwin we have a predominant
+application of _induction_, and a prudent concern to establish the
+different parts of the theory of selection as firmly as possible on a
+basis of observation and experiment. While the French scientist far
+outran the then limits of empirical knowledge, and rather sketched the
+programme of future investigation, the English empiricist was mainly
+preoccupied about securing a unifying principle of interpretation for
+a mass of empirical knowledge which had hitherto accumulated without
+being understood. We can thus understand how it was that the success
+of Darwin was just as overwhelming as that of Lamarck was evanescent.
+Darwin, however, had not only the signal merit of bringing all the
+results of the various biological sciences to a common focus in the
+principle of descent, and thus giving them a harmonious interpretation,
+but he also discovered, in the principle of selection, that direct
+cause of transformation which Lamarck had missed. In applying, as a
+practical breeder, the experience of artificial selection to organisms
+in a state of nature, and in recognizing in the "struggle for life" the
+selective principle of natural selection, Darwin created his momentous
+"theory of selection," which is what we properly call Darwinism.
+
+One of the most pressing of the many important tasks which Darwin
+proposed to modern biology was the reform of the zoological and
+botanical system. Since the innumerable species of animals and plants
+were not created by a supernatural miracle, but evolved by natural
+processes, their ancestral tree is their "natural system." The first
+attempt to frame a system in this sense was made by myself in 1866,
+in my _General Morphology of Organisms_. The first volume of this
+work ("General Anatomy") dealt with the "mechanical science of the
+developed forms"; the second volume ("General Evolution") was occupied
+with the science of the "developing forms." The systematic introduction
+to the latter formed a "genealogical survey of the natural system
+of organisms." Until that time the term "evolution" had been taken
+to mean exclusively, both in zoology and botany, the development of
+individual organisms--embryology, or metamorphic science. I established
+the opposite view, that this history of the embryo (ontogeny) must be
+completed by a second, equally valuable, and closely connected branch
+of thought--the history of the race (phylogeny). Both these branches
+of evolutionary science are, in my opinion, in the closest causal
+connection; this arises from the reciprocal action of the laws of
+heredity and adaptation; it has a precise and comprehensive expression
+in my "fundamental law of biogeny."
+
+As the new views I had put forward in my _General Morphology_ met with
+very little notice, and still less acceptance, from my scientific
+colleagues, in spite of their severely scientific setting, I thought
+I would make the most important of them accessible to a wider circle
+of informed readers by a smaller work, written in a more popular
+style. This was done in 1868, in _The Natural History of Creation_ (a
+series of popular scientific lectures on evolution in general, and the
+systems of Darwin, Goethe, and Lamarck in particular). If the success
+of my _General Morphology_ was far below my reasonable anticipation,
+that of _The Natural History of Creation_ went far beyond it. In a
+period of thirty years nine editions and twelve different translations
+of it have appeared. In spite of its great defects, the book has
+contributed much to the popularization of the main ideas of modern
+evolution. Still, I could only give the barest outlines in it of my
+chief object, the phylogenetic construction of a natural system. I
+have, therefore, given the complete proof, which is wanting in the
+earlier work, of the phylogenetic system in a subsequent larger work,
+my _Systematic Phylogeny_ (outlines of a natural system of organisms
+on the basis of their specific development). The first volume of
+it deals with the protists and plants (1894), the second with the
+invertebrate animals (1896), the third with the vertebrates (1895). The
+ancestral tree of both the smaller and the larger groups is carried
+on in this work as far as my knowledge of the three great "ancestral
+documents"--palæontology, ontogeny, and morphology--qualified me to
+extend it.
+
+I had already, in my _General Morphology_ (at the end of the fifth
+book), described the close causative connection which exists, in
+my opinion, between the two branches of organic evolution as one
+of the most important ideas of transformism, and I had framed a
+precise formula for it in a number of "theses on the causal nexus of
+biontic and phyletic development": "_Ontogenesis is a brief and rapid
+recapitulation of phylogenesis_, determined by the physiological
+functions of heredity (generation) and adaptation (maintenance)."
+Darwin himself had emphasized the great significance of his theory
+for the elucidation of embryology in 1859, and Fritz Müller had
+endeavored to prove it as regards the Crustacea in the able little
+work, _Facts and Arguments for Darwin_ (1864). My own task has been
+to prove the universal application and the fundamental importance of
+the biogenetic law in a series of works, especially in the _Biology
+of the Calcispongiae_ (1872), and in _Studies on the Gastraea Theory_
+(1873-1884). The theory of the homology of the germinal layers and of
+the relations of _palingenesis_ to _cenogenesis_ which I have exposed
+in them has been confirmed subsequently by a number of works of other
+zoologists. That theory makes it possible to follow nature's law of
+unity in the innumerable variations of animal embryology; it gives us
+for their ancestral history a common derivation from a simple primitive
+stem form.
+
+The far-seeing founder of the theory of descent, Lamarck, clearly
+recognized in 1809 that it was of universal application; that even man
+himself, the most highly developed of the mammals, is derived from the
+same stem as all the other mammals; and that this in its turn belongs
+to the same older branch of the ancestral tree as the rest of the
+vertebrates. He had even indicated the agencies by which it might be
+possible to explain man's descent from the apes as the nearest related
+mammals. Darwin, who was, naturally, of the same conviction, purposely
+avoided this least acceptable consequence of his theory in his chief
+work in 1859, and put it forward for the first time in his _Descent of
+Man_ in 1871. In the mean time (1863) Huxley had very ably discussed
+this most important consequence of evolution in his famous _Place of
+Man in Nature_. With the aid of comparative anatomy and ontogeny,
+and the support of the facts of palæontology, Huxley proved that the
+"descent of man from the ape" is a necessary consequence of Darwinism,
+and that no other scientific explanation of the origin of the human
+race is possible. Of the same opinion was Karl Gegenbaur, the most
+distinguished representative of comparative anatomy, who lifted his
+science to a higher level by a consistent and ingenious application of
+the theory of descent.
+
+As a further consequence of the "pithecoid theory" (the theory of the
+descent of man from the ape) there now arose the difficult task of
+investigating, not only the nearest related mammal ancestors of man
+in the Tertiary epoch, but also the long series of the older animal
+ancestors which had lived in earlier periods of the earth's history and
+been developed in the course of countless millions of years. I had made
+a start with the hypothetical solution of this great historic problem
+in my _General Morphology_; a further development of it appeared in
+1874 in my _Anthropogeny_ (first section, Origin of the Individual;
+second section, Origin of the Race). The fourth, enlarged, edition of
+this work (1891) contains that theory of the development of man which
+approaches nearest, in my own opinion, to the still remote truth, in
+the light of our present knowledge of the documentary evidence. I was
+especially preoccupied in its composition to use the three empirical
+"documents"--palæontology, ontogeny, and morphology (or comparative
+anatomy)--as evenly and harmoniously as possible. It is true that my
+hypotheses were in many cases supplemented and corrected in detail by
+later phylogenetic research; yet I am convinced that the ancestral tree
+of human origin which I have sketched therein is substantially correct.
+For the historical succession of vertebrate fossils corresponds
+completely with the morphological evolutionary scale which is revealed
+to us by comparative anatomy and ontogeny. After the Silurian fishes
+come the _dipnoi_ of the Devonian period--the Carboniferous amphibia,
+the Permian reptilia, and the Mesozoic mammals. Of these, again, the
+lowest forms, the monotremes, appear first in the Triassic period,
+the marsupials in the Jurassic, and then the oldest placentals in
+the Cretaceous. Of the placentals, in turn, the first to appear in
+the oldest Tertiary period (the Eocene) are the lowest primates,
+the prosimiæ, which are followed by the simiæ in the Miocene. Of the
+catarrhinæ, the cynopitheci precede the anthropomorpha; from one branch
+of the latter, during the Pliocene period, arises the ape-man without
+speech (the _pithecanthropus alalus_); and from him descends, finally,
+speaking man.
+
+The chain of our earlier invertebrate ancestors is much more difficult
+to investigate and much less safe than this tree of our vertebrate
+predecessors; we have no fossilized relics of their soft, boneless
+structures, so palæontology can give us no assistance in this case.
+The evidence of comparative anatomy and ontogeny, therefore, becomes
+all the more important. Since the human embryo passes through the
+same _chordula_-stage as the germs of all other vertebrates, since
+it evolves, similarly, out of two germinal layers of a _gastrula_,
+we infer, in virtue of the biogenetic law, the early existence of
+corresponding ancestral forms--vermalia, gastræada, etc. Most important
+of all is the fact that the human embryo, like that of all other
+animals, arises originally from a single cell; for this "stem-cell"
+(_cytula_)--the impregnated egg cell--points indubitably to a
+corresponding unicellular ancestor, a primitive, Laurentian protozoon.
+
+For the purpose of our monistic philosophy, however, it is a matter of
+comparative indifference how the succession of our animal predecessors
+may be confirmed in detail. Sufficient for us, as an incontestable
+historical fact, is the important thesis that man descends immediately
+from the ape, and secondarily from a long series of lower vertebrates.
+I have laid stress on the logical proof of this "pithecometra-thesis"
+in the seventh book of the _General Morphology_: "The thesis that
+man has been evolved from lower vertebrates, and immediately from the
+_simiae_, is a special inference which results with absolute necessity
+from the general inductive law of the theory of descent."
+
+For the definitive proof and establishment of this fundamental
+pithecometra-thesis the palæontological discoveries of the last
+thirty years are of the greatest importance; in particular, the
+astonishing discoveries of a number of extinct mammals of the Tertiary
+period have enabled us to draw up clearly in its main outlines the
+evolutionary history of this most important class of animals, from
+the lowest oviparous monotremes up to man. The four chief groups
+of the placentals, the heterogeneous legions of the carnassia, the
+rodentia, the ungulata, and the primates, seem to be separated by
+profound gulfs, when we confine our attention to their representatives
+of to-day. But these gulfs are completely bridged, and the sharp
+distinctions of the four legions are entirely lost, when we compare
+their extinct predecessors of the Tertiary period, and when we go
+back into the Eocene twilight of history, in the oldest part of the
+Tertiary period--at least three million years ago. There we find the
+great sub-class of the placentals, which to-day comprises more than
+two thousand five hundred species, represented by only a small number
+of little, insignificant "proplacentals"; and in these _prochoriata_
+the characters of the four divergent legions are so intermingled and
+toned down that we cannot in reason do other than consider them as the
+precursors of those features. The oldest carnassia (the _ictopsales_),
+the oldest rodentia (the _esthonychales_), the oldest ungulata (the
+_condylarthrales_) and the oldest primates (the _lemuravales_), all
+have the same fundamental skeletal structure, and the same typical
+dentition of the primitive placentals, consisting of forty-four teeth
+(three incisors, one canine, four premolars, and three molars in each
+half of the jaw); all are characterized by the small size and the
+imperfect structure of the brain (especially of its chief part, the
+cortex, which does not become a true "organ of thought" until later on
+in the Miocene and Pliocene representatives); they have all short legs
+and five-toed, flat-soled feet (_plantigrada_). In many cases among
+these oldest placentals of the Eocene period it was very difficult
+to say at first whether they should be classed with the carnassia,
+rodentia, ungulata, or primates; so very closely, even to confusion,
+do these four groups of the placentals, which diverge so widely
+afterwards, approach each other at that time. Their common origin from
+a single ancestral group follows incontestably. These _prochoriata_
+lived in the preceding Cretaceous period (more than three million years
+ago), and were probably developed in the Jurassic period from a group
+of insectivorous marsupials (_amphitheria_) by the formation of a
+primitive _placenta diffusa_, a placenta of the simplest type.
+
+But the most important of all the recent palaeontological discoveries
+which have served to elucidate the origin of the placentals relate
+to our own stem, the legion of primates. Formerly fossil remains of
+the primates were very scarce. Even Cuvier, the great founder of
+palaeontology, maintained until his last day (1832) that there were no
+fossilized primates; he had himself, it is true, described the skull
+of an Eocene prosimiæ (_adapis_), but he had wrongly classed it with
+the ungulata. However, during the last twenty years a fair number of
+well-preserved fossilized skeletons of prosimiæ and simiæ have been
+discovered; in them we find all the chief intermediate members which
+complete the connecting chain of ancestors from the oldest prosimiæ to
+man.
+
+The most famous and most interesting of these discoveries is the
+fossil ape-man of Java, the much-talked-of _pithecanthropus erectus_,
+found by a Dutch military doctor, Eugen Dubois, in 1894. It is in
+truth the much-sought "missing link," supposed to be wanting in
+the chain of primates, which stretches unbroken from the lowest
+catarrhinæ to the highest-developed man. I have dealt exhaustively
+with the significance of this discovery in the paper which I read on
+August 26, 1898, at the Fourth International Zoological Congress at
+Cambridge.[13] The palæontologist, who knows the conditions of the
+formation and preservation of fossils, will think the discovery of the
+pithecanthropus an unusually lucky accident. The apes, being arboreal,
+seldom came into the circumstances (unless they happened to fall into
+the water) which would secure the preservation and petrifaction of
+their skeleton. Thus, by the discovery of this fossil man-monkey of
+Java the descent of man from the ape has become just as clear and
+certain from the palæontological side as it was previously from the
+evidence of comparative anatomy and ontogeny. We now have all the
+principal documents which tell the history of our race.
+
+
+
+
+CHAPTER VI
+
+THE NATURE OF THE SOUL
+
+    Fundamental Importance of Psychology--Its Definition and
+    Methods--Divergence of Views Thereon--Dualistic and Monistic
+    Psychology--Relation to the Law of Substance--Confusion
+    of Ideas--Psychological Metamorphoses: Kant, Virchow,
+    Du Bois-Reymond--Methods of Research of Psychic
+    Science--Introspective Method (Self-Observation)--Exact
+    Method (Psycho-Physics)--Comparative Method (Animal
+    Psychology)--Psychological Change of Principles:
+    Wundt--Folk-Psychology and Ethnography: Bastian--Ontogenetic
+    Psychology: Preyer--Phylogenetic Psychology: Darwin, Romanes
+
+
+The phenomena which are comprised under the title of the "life of
+the soul," or the psychic activity, are, on the one hand, the most
+important and interesting, on the other the most intricate and
+problematical, of all the phenomena we are acquainted with. As the
+knowledge of nature, the object of the present philosophic study,
+is itself a part of the life of the soul, and as anthropology, and
+even cosmology, presuppose a correct knowledge of the "psyche," we
+may regard psychology, the scientific study of the soul, both as the
+foundation and the postulate of all other sciences. From another
+point of view it is itself a part of philosophy, or physiology, or
+anthropology.
+
+The great difficulty of establishing it on a naturalistic basis
+arises from the fact that psychology, in turn, presupposes a correct
+acquaintance with the human organism, especially the brain, the chief
+organ of psychic activity. The great majority of "psychologists" have
+little or no acquaintance with these anatomical foundations of the
+soul, and thus it happens that in no other science do we find such
+contradictions and untenable notions as to its proper meaning and
+its essential object as are current in psychology. This confusion
+has become more and more palpable during the last thirty years, in
+proportion as the immense progress of anatomy and physiology has
+increased our knowledge of the structure and the functions of the chief
+psychic organ.
+
+What we call the soul is, in my opinion, a natural phenomenon; I
+therefore consider psychology to be a branch of natural science--a
+section of physiology. Consequently, I must emphatically assert
+from the commencement that we have no different methods of research
+for that science than for any of the others; we have in the first
+place observation and experiment, in the second place the theory of
+evolution, and in the third place metaphysical speculation, which
+seek to penetrate as far as possible into the cryptic nature of the
+phenomena by inductive and deductive reasoning. However, with a view
+to a thorough appreciation of the question, we must first of all put
+clearly before the reader the antithesis of the dualistic and the
+monistic theories.
+
+The prevailing conception of the psychic activity, which we contest,
+considers soul and body to be two distinct entities. These two
+entities can exist independently of each other; there is no intrinsic
+necessity for their union. The organized body is a mortal, material
+nature, chemically composed of living protoplasm and its compounds
+(plasma-products). The soul, on the other hand, is an immortal,
+immaterial being, a spiritual agent, whose mysterious activity
+is entirely incomprehensible to us. This trivial conception is,
+as such, spiritualistic, and its contradictory is, in a certain
+sense, materialistic. It is, at the same time, supernatural and
+transcendental, since it affirms the existence of forces which can
+exist and operate without a material basis; it rests on the assumption
+that outside of and beyond nature there is a "spiritual," immaterial
+world, of which we have no experience, and of which we can learn
+nothing by natural means.
+
+This hypothetical "spirit world," which is supposed to be entirely
+independent of the material universe, and on the assumption of which
+the whole artificial structure of the dualistic system is based, is
+purely a product of poetic imagination; the same must be said of the
+parallel belief in the "immortality of the soul," the scientific
+impossibility of which we must prove more fully later on (chap. xi.).
+If the beliefs which prevail in these credulous circles had a sound
+foundation, the phenomena they relate to could not be subject to the
+"law of substance"; moreover, this single exception to the highest
+law of the cosmos must have appeared very late in the history of the
+organic world, since it only concerns the "soul" of man and of the
+higher animals. The dogma of "free will," another essential element
+of the dualistic psychology, is similarly irreconcilable with the
+universal law of substance.
+
+Our own naturalistic conception of the psychic activity sees in it a
+group of vital phenomena, which are dependent on a definite material
+substratum, like all other phenomena. We shall give to this material
+basis of all psychic activity, without which it is inconceivable,
+the provisional name of "psychoplasm"; and for this good reason--that
+chemical analysis proves it to be a body of the group we call
+protoplasmic bodies the albuminoid carbon-combinations which are at
+the root of all vital processes. In the higher animals, which have a
+nervous system and sense-organs, "neuroplasm," the nerve-material,
+has been differentiated out of psychoplasm. Our conception is, in
+this sense, materialistic. It is at the same time empirical and
+naturalistic, for our scientific experience has never yet taught us the
+existence of forces that can dispense with a material substratum, or of
+a spiritual world over and above the realm of nature.
+
+Like all other natural phenomena, the psychic processes are subject to
+the supreme, all-ruling law of substance; not even in this province
+is there a single exception to this highest cosmological law (compare
+chap. xii.). The phenomena of the lowly psychic life of the unicellular
+protist and the plant, and of the lowest animal forms--their
+irritability, their reflex movements, their sensitiveness and instinct
+of self-preservation--are directly determined by physiological action
+in the protoplasm of their cells--that is, by physical and chemical
+changes which are partly due to heredity and partly to adaptation.
+And we must say just the same of the higher psychic activity of the
+higher animals and man, of the formation of ideas and concepts, of
+the marvellous phenomena of reason and consciousness; for the latter
+have been phylogenetically evolved from the former, and it is merely
+a higher degree of integration or centralization, of association
+or combination of functions which were formerly isolated, that has
+elevated them in this manner.
+
+The first task of every science is the clear definition of the object
+it has to investigate. In no science, however, is this preliminary
+task so difficult as in psychology; and this circumstance is the
+more remarkable since logic, the science of defining, is itself a
+part of psychology. When we compare all that has been said by the
+most distinguished philosophers and scientists of all ages on the
+fundamental idea of psychology, we find ourselves in a perfect chaos
+of contradictory notions. What, really, is the "soul"? What is its
+relation to the "mind"? What is the inner meaning of "consciousness"?
+What is the difference between "sensation" and "sentiment"? What is
+"instinct"? What is the meaning of "free will"? What is "presentation"?
+What is the difference between "intellect" and "reason"? What is the
+true nature of "emotion"? What is the relation between all these
+"psychic phenomena" and the "body"? The answers to these and many other
+cognate questions are infinitely varied; not only are the views of the
+most eminent thinkers on these questions widely divergent, but even the
+same scientific authority has often completely changed his views in the
+course of his psychological development. Indeed, this "psychological
+metamorphosis" of so many thinkers has contributed not a little to the
+_colossal confusion of ideas_ which prevails in psychology more than in
+any other branch of knowledge.
+
+The most interesting example of such an entire change of objective
+and subjective psychological opinions is found in the case of the
+most influential leader of German philosophy, Immanuel Kant. The
+young, severely _critical_ Kant came to the conclusion that the three
+great buttresses of mysticism--"God, freedom, and immortality"--were
+untenable in the light of "pure reason"; the older, _dogmatic_ Kant
+found that these three great hallucinations were postulates of
+"practical reason," and were, as such, indispensable. The more the
+distinguished modern school of "Neokantians" urges a "return to Kant"
+as the only possible salvation from the frightful jumble of modern
+metaphysics, the more clearly do we perceive the undeniable and fatal
+contradiction between the fundamental opinions of the young and the
+older Kant. We shall return to this point later on.
+
+Other interesting examples of this change of views are found in two of
+the most famous living scientists, R. Virchow and E. du Bois-Reymond;
+the metamorphoses of their fundamental views on psychology cannot
+be overlooked, as both these Berlin biologists have played a most
+important part at Germany's greatest university for more than forty
+years, and have, therefore, directly and indirectly, had a most
+profound influence on the modern mind. Rudolph Virchow, the eminent
+founder of cellular pathology, was a _pure monist_ in the best days of
+his scientific activity, about the middle of the century; he passed at
+that time as one of the most distinguished representatives of the newly
+awakened _materialism_, which appeared in 1855, especially through two
+famous works, almost contemporaneous in appearance--Ludwig Büchner's
+_Matter and Force_ and Carl Vogt's _Superstition and Science_. Virchow
+published his general biological views on the vital processes in
+man--which he takes to be purely mechanical natural phenomena--in a
+series of distinguished papers in the first volumes of the _Archiv
+für pathologische Anatomie_, which he founded. The most important of
+these articles, and the one in which he most clearly expresses his
+monistic views of that period, is that on "The Tendencies Towards
+Unity in Scientific Medicine" (1849). It was certainly not without
+careful thought, and a conviction of its philosophic value, that
+Virchow put this "medical confession of faith" at the head of his
+_Collected Essays on Scientific Medicine_ in 1856. He defended in it,
+clearly and definitely, the fundamental principles of monism, which I
+am presenting here with a view to the solution of the world-problem;
+he vindicated the exclusive title of empirical science, of which the
+only reliable sources are sense and brain activity; he vigorously
+attacked anthropological dualism, the alleged "revelation," and
+the transcendental philosophy, with their two methods--"faith and
+anthropomorphism." Above all, he emphasized the monistic character of
+anthropology, the inseparable connection of spirit and body, of force
+and matter. "I am convinced," he exclaims, at the end of his preface,
+"that I shall never find myself compelled to deny the thesis of _the
+unity_ of human nature." Unhappily, this "conviction" proved to be a
+grave error. Twenty-eight years afterwards Virchow represented the
+diametrically opposite view; it is to be found in the famous speech on
+"The Liberty of Science in Modern States," which he delivered at the
+Scientific Congress at Munich in 1877, and which contains attacks that
+I have repelled in my _Free Science and Free Teaching_ (1878).
+
+In Emil du Bois-Reymond we find similar contradictions with regard
+to the most important and fundamental theses of philosophy. The
+more completely the distinguished orator of the Berlin Academy had
+defended the main principles of the monistic philosophy, the more he
+had contributed to the refutation of vitalism and the transcendental
+view of life, so much the louder was the triumphant cry of our
+opponents when in 1872, in his famous _Ignorabimus-Speech_, he spoke
+of consciousness as an insoluble problem, and opposed it to the other
+functions of the brain as a supernatural phenomenon. I return to the
+point in the tenth chapter.
+
+The peculiar character of many of the psychic phenomena, especially
+of consciousness, necessitates certain modifications of our ordinary
+scientific methods. We have, for instance, to associate with the
+customary _objective_, external observation, the _introspective_
+method, the _subjective_, internal observation which scrutinizes
+our own personality in the mirror of consciousness. The majority of
+psychologists have started from this "certainty of the ego": "_Cogito
+ergo sum_," as Descartes said--I think, therefore I am. Let us first
+cast a glance at this way of inquiry, and then deal with the second,
+complementary, method.
+
+By far the greater part of the theories of the soul which have been
+put forward during the last two thousand years or more are based on
+introspective inquiry--that is, on "self-observation," and on the
+conclusions which we draw from the association and criticism of these
+subjective experiences. Introspection is the only possible method of
+inquiry for an important section of psychology, especially for the
+study of consciousness. Hence this cerebral function occupies a special
+position, and has been a more prolific source of philosophic error than
+any of the others (cf. chap. x.). It is, however, most unsatisfactory,
+and it leads to entirely false or incomplete notions, to take this
+self-observation of the mind to be the chief, or, especially, to be
+the only source of mental science, as has happened in the case of
+many and distinguished philosophers. A great number of the principal
+psychic phenomena, particularly the activity of the senses and speech,
+can only be studied in the same way as every other vital function of
+the organism--that is, firstly, by a thorough anatomical study of
+their organs, and, secondly, by an exact physiological analysis of
+the functions which depend on them. In order, however, to complete
+this external study of the mental life, and to supplement the results
+of _internal_ observation, one needs a thorough knowledge of human
+anatomy, histology, ontogeny, and physiology. Most of our so-called
+"psychologists" have little or no knowledge of these indispensable
+foundations of anthropology; they are, therefore, incompetent to
+pronounce on the character even of their own "soul." It must be
+remembered, too, that the distinguished personality of one of these
+psychologists usually offers a specimen of an educated mind of the
+highest civilized races; it is the last link of a long ancestral chain,
+and the innumerable older and inferior links are indispensable for
+its proper understanding. Hence it is that most of the psychological
+literature of the day is so much waste paper. The introspective method
+is certainly extremely valuable and indispensable; still it needs the
+constant co-operation and assistance of the other methods.
+
+In proportion as the various branches of the human tree of knowledge
+have developed during the century, and the methods of the different
+sciences have been perfected, the desire has grown to make them
+_exact_; that is, to make the study of phenomena as purely empirical
+as possible, and to formulate the laws that result as clearly as
+the circumstances permit--if possible, _mathematically_. The latter
+is, however, only feasible in a small province of human knowledge,
+especially in those sciences in which there is question of measurable
+quantities; in mathematics, in the first place, and to a greater or
+less extent in astronomy, mechanics, and a great part of physics and
+chemistry. Hence these studies are called "exact sciences" in the
+narrower sense. It is, however, productive only of error to call all
+the physical sciences _exact_, and oppose them to the historical,
+mental, and moral sciences. The greater part of physical science can
+no more be treated as an _exact_ science than history can; this is
+especially true of biology and of its subsidiary branch, psychology.
+As psychology is a part of physiology, it must, as a general rule,
+follow the chief methods of that science. It must establish the facts
+of psychic activity by empirical methods as much as possible, by
+observation and experiment, and it must then gather the laws of the
+mind by inductive and deductive inferences from its observations,
+and formulate them with the utmost distinctness. But, for obvious
+reasons, it is rarely possible to formulate them mathematically. Such
+a procedure is only profitable in one section of the physiology of
+the senses; it is not practicable in the greater part of cerebral
+physiology.
+
+One small section of physiology, which seems amenable to the "exact"
+method of investigation, has been carefully studied for the last
+twenty years and raised to the position of a separate science under
+the title of _psycho-physics_. Its founders, the physiologists Theodor
+Fechner and Ernst Heinrich Weber, first of all closely investigated
+the dependence of sensations on the external stimuli that act on the
+organs of sense, and particularly the quantitative relation between
+the strength of the stimulus and the intensity of the sensation. They
+found that a certain minimum strength of stimulus is requisite for
+the excitement of a sensation, and that a given stimulus must be
+varied to a definite amount before there is any perceptible change
+in the sensation. For the highest sensations (of sight, hearing, and
+pressure) the law holds good that their variations are proportionate
+to the changes in the strength of the stimulus. From this empirical
+"law of Weber" Fechner inferred, by mathematical operations, his
+"fundamental law of psycho-physics," according to which the intensity
+of a sensation increases in arithmetical progression, the strength
+of the stimulus in geometrical progression. However, Fechner's law
+and other psycho-physical laws are frequently contested, and their
+"exactness" is called into question. In any case modern psycho-physics
+has fallen far short of the great hopes with which it was greeted
+twenty years ago; the field of its applicability is extremely limited.
+One important result of its work is that it has proved the application
+of physical laws in one, if only a small, branch of the life of the
+"soul"--an application which was long ago postulated on principle by
+the materialist psychology for the whole province of mental life. In
+this, as in many other branches of physiology, the "exact" method has
+proved inadequate and of little service. It is the ideal to aim at
+everywhere, but it is unattainable in most cases. Much more profitable
+are the comparative and genetic methods.
+
+The striking resemblance of man's psychic activity to that of
+the higher animals--especially our nearest relatives among the
+mammals--is a familiar fact. Most uncivilized races still make no
+material distinction between the two sets of mental processes, as
+the well-known animal fables, the old legends, and the idea of the
+transmigration of souls prove. Even most of the philosophers of
+classical antiquity shared the same conviction, and discovered no
+essential qualitative difference, but merely a quantitative one,
+between the soul of man and that of the brute. Plato himself, who was
+the first to draw a fundamental distinction between soul and body,
+made one and the same soul (or "idea") pass through a number of animal
+and human bodies in his theory of metempsychosis. It was Christianity,
+intimately connecting faith in immortality with faith in God, that
+emphasized the essential difference of the immortal soul of man from
+the mortal soul of the brute. In the dualistic philosophy the idea
+prevailed principally through the influence of Descartes (1643);
+he contended that man alone had a true "soul," and, consequently,
+sensation and free will, and that the animals were mere automata, or
+machines, without will or sensibility. Ever since the majority of
+psychologists--including even Kant--have entirely neglected the mental
+life of the brute, and restricted psychological research to man:
+human psychology, mainly introspective, dispensed with the fruitful
+comparative method, and so remained at that lower point of view which
+human morphology took before Cuvier raised it to the position of a
+"philosophic science" by the foundation of comparative anatomy.
+
+Scientific interest in the psychic activity of the brute was revived
+in the second half of the last century, in connection with the
+advance of systematic zoology and physiology. A strong impulse was
+given to it by the work of Reimarus: "General observations on the
+instincts of animals" (Hamburg, 1760). At the same time a deeper
+scientific investigation had been facilitated by the thorough reform
+of physiology by Johannes Müller. This distinguished biologist, having
+a comprehensive knowledge of the whole field of organic nature, of
+morphology, and of physiology, introduced the "exact methods" of
+observation and experiment into the whole province of physiology, and,
+with consummate skill, combined them with the comparative methods. He
+applied them, not only to mental life in the broader sense (to speech,
+senses, and brain-action), but to all the other phenomena of life. The
+sixth book of his _Manual of Human Physiology_ treats specially of the
+life of the soul, and contains eighty pages of important psychological
+observations.
+
+During the last forty years a great number of works on comparative
+animal psychology have appeared, principally occasioned by the great
+impulse which Darwin gave in 1859 by his work on _The Origin of
+Species_, and by the application of the idea of evolution to the
+province of psychology. The more important of these works we owe to
+Romanes and Sir J. Lubbock, in England; to W. Wundt, L. Büchner, G.
+Schneider, Fritz Schultze, and Karl Groos, in Germany; to Alfred
+Espinas and E. Jourdan, in France; and to Tito Vignoli, in Italy.
+
+In Germany, Wilhelm Wundt, of Leipzig, is considered to be the ablest
+living psychologist; he has the inestimable advantage over most other
+philosophers of a thorough zoological, anatomical, and physiological
+education. Formerly assistant and pupil of Helmholtz, Wundt had early
+accustomed himself to follow the application of the laws of physics and
+chemistry through the whole field of physiology, and, consequently,
+in the sense of Johannes Müller, in _psychology_, as a subsection
+of the latter. Starting from this point of view, Wundt published
+his valuable "Lectures on human and animal psychology" in 1863. He
+proved, as he himself tells us in the preface, that the theatre of
+the most important psychic processes is in the "unconscious soul,"
+and he affords us "a view of the mechanism which, in the unconscious
+background of the soul, manipulates the impressions which arise
+from the external stimuli." What seems to me, however, of special
+importance and value in Wundt's work is that he "extends the law of the
+persistence of force for the first time to the psychic world, and makes
+use of a series of facts of electro-physiology by way of demonstration."
+
+Thirty years afterwards (1892) Wundt published a second, much
+abridged and entirely modified, edition of his work. The important
+principles of the first edition are entirely abandoned in the second,
+and the monistic is exchanged for a purely dualistic stand-point.
+Wundt himself says in the preface to the second edition that he has
+emancipated himself from the fundamental errors of the first, and
+that he "learned many years ago to consider the work a sin of his
+youth"; it "weighed on him as a kind of crime, from which he longed
+to free himself as soon as possible." In fact, the most important
+systems of psychology are completely opposed to each other in the two
+editions of Wundt's famous _Observations_. In the first edition he
+is purely monistic and materialistic, in the second edition purely
+dualistic and spiritualistic. In the one psychology is treated as a
+_physical_ science, on the same laws as the whole of physiology, of
+which it is only a part; thirty years afterwards he finds psychology
+to be a _spiritual_ science, with principles and objects entirely
+different from those of physical science. This conversion is most
+clearly expressed in his principle of psycho-physical parallelism,
+according to which "every psychic event has a corresponding physical
+change"; but the two are completely independent, and are not in any
+natural causal connection. This complete dualism of body and soul,
+of nature and mind, naturally gave the liveliest satisfaction to the
+prevailing school-philosophy, and was acclaimed by it as an important
+advance, especially seeing that it came from a distinguished scientist
+who had previously adhered to the opposite system of monism. As I
+myself continue, after more than forty years' study, in this "narrow"
+position, and have not been able to free myself from it in spite of
+all my efforts, I must naturally consider the "youthful sin" of the
+young physiologist Wundt to be a correct knowledge of nature, and
+energetically defend it against the antagonistic view of the old
+philosopher Wundt.
+
+This entire change of philosophical principles, which we find in Wundt,
+as we found it in Kant, Virchow, Du Bois-Reymond, Karl Ernst Baer, and
+others, is very interesting. In their youth these able and talented
+scientists embrace the whole field of biological research in a broad
+survey, and make strenuous efforts to find a unifying, natural basis
+for their knowledge; in their later years they have found that this is
+not completely attainable, and so they entirely abandon the idea. In
+extenuation of these psychological metamorphoses they can, naturally,
+plead that in their youth they overlooked the difficulties of the great
+task, and misconceived the true goal; with the maturer judgment of age
+and the accumulation of experience they were convinced of their errors,
+and discovered the true path to the source of truth. On the other hand,
+it is possible to think that great scientists approach their task with
+less prejudice and more energy in their earlier years--that their
+vision is clearer and their judgment purer; the experiences of later
+years sometimes have the effect, not of enriching, but of disturbing,
+the mind, and with old age there comes a gradual decay of the brain,
+just as happens in all other organs. In any case, this change of views
+is in itself an instructive psychological fact; because, like many
+other forms of change of opinion, it shows that the highest psychic
+functions are subject to profound individual changes in the course of
+life, like all the other vital processes.
+
+For the profitable construction of comparative psychology it is
+extremely important not to confine the critical comparison to man
+and the brute in general, but to put side by side the innumerable
+gradations of their mental activity. Only thus can we attain a clear
+knowledge of the long scale of psychic development which runs unbroken
+from the lowest, unicellular forms of life up to the mammals, and to
+man at their head. But even within the limits of our own race such
+gradations are very noticeable, and the ramifications of the "psychic
+ancestral tree" are very numerous. The psychic difference between the
+crudest savage of the lowest grade and the most perfect specimen of
+the highest civilization is colossal--much greater than is commonly
+supposed. By the due appreciation of this fact, especially in the
+latter half of the century, the "Anthropology of the uncivilized races"
+(Waitz) has received a strong support, and comparative ethnography has
+come to be considered extremely important for psychological purposes.
+Unfortunately, the enormous quantity of raw material of this science
+has not yet been treated in a satisfactory critical manner. What
+confused and mystic ideas still prevail in this department may be seen,
+for instance, in the _Völkergedanke_ of the famous traveller, Adolf
+Bastian, who, though a prolific writer, merely turns out a hopeless
+mass of uncritical compilation and confused speculation.
+
+The most neglected of all psychological methods, even up to the present
+day, is the evolution of the soul; yet this little-frequented path
+is precisely the one that leads us most quickly and securely through
+the gloomy primeval forest of psychological prejudices, dogmas, and
+errors, to a clear insight into many of the chief psychic problems. As
+I did in the other branch of organic evolution, I again put before the
+reader the two great branches of the science which I differentiated in
+1866--ontogeny and phylogeny. The ontogeny, or embryonic development,
+of the soul, individual or biontic psychogeny, investigates the gradual
+and hierarchic development of the soul in the individual, and seeks to
+learn the laws by which it is controlled. For a great part of the life
+of the mind a good deal has been done in this direction for centuries;
+rational pedagogy must have set itself the task at an early date of the
+theoretical study of the gradual development and formative capacity of
+the young mind that was committed to it for education and formation.
+Most pedagogues, however, were idealistic or dualistic philosophers,
+and so they went to work with all the prejudices of the spiritualistic
+psychology. It is only in the last few decades that this dogmatic
+tendency has been largely superseded even in the school by scientific
+methods; we now find a greater concern to apply the chief laws of
+evolution even in the discussion of the soul of the child. The raw
+material of the child's soul is already qualitatively determined by
+_heredity_ from parents and ancestors; education has the noble task of
+bringing it to a perfect maturity by intellectual instruction and moral
+training--that is, by _adaptation_. Wilhelm Preyer was the first to
+lay the foundation of our knowledge of the early psychic development
+in his interesting work on _The Mind of the Child_. Much is still to
+be done in the study of the later stages and metamorphoses of the
+individual soul, and once more the correct, critical application of the
+biogenetic law is proving a guiding star to the scientific mind.
+
+A new and fertile epoch of higher development dawned for psychology
+and all other biological sciences when Charles Darwin applied the
+principles of evolution to them forty years ago. The seventh chapter
+of his epoch-making work on _The Origin of Species_ is devoted to
+instinct. It contains the valuable proof that the instincts of animals
+are subject, like all other vital processes, to the general laws of
+historic development. The special instincts of particular species were
+formed by _adaptation_, and the modifications thus acquired were handed
+on to posterity by _heredity_; in their formation and preservation
+natural selection plays the same part as in the transformation of
+every other physiological function. Darwin afterwards developed this
+fundamental thought in a number of works, showing that the same laws of
+"mental evolution" hold good throughout the entire organic world, not
+less in man than in the brute, and even in the plant. Hence the unity
+of the organic world, which is revealed by the common origin of its
+members, applies also to the entire province of psychic life, from the
+simplest unicellular organism up to man.
+
+To George Romanes we owe the further development of Darwin's
+psychology and its special application to the different sections of
+psychic activity. Unfortunately, his premature decease prevented the
+completion of the great work which was to reconstruct every section
+of comparative psychology on the lines of monistic evolution. The
+two volumes of this work which were completed are among the most
+valuable productions of psychological literature. For, conformably
+to the principles of our modern monistic research, his first care
+was to collect and arrange all the important facts which have been
+empirically established in the field of comparative psychology in the
+course of centuries; in the second place, these facts are tested with
+an _objective criticism_, and systematically distributed; finally, such
+rational conclusions are drawn from them on the chief general questions
+of psychology as are in harmony with the fundamental principles of
+modern monism. The first volume of Romanes's work bears the title
+of _Mental Evolution in the Animal World_; it presents, in natural
+connection, the entire length of the chain of psychic evolution in the
+animal world, from the simplest sensations and instincts of the lowest
+animals to the elaborate phenomena of consciousness and reason in the
+highest. It contains also a number of extracts from a manuscript which
+Darwin left "on instinct," and a complete collection of all that he
+wrote in the province of psychology.
+
+The second and more important volume of Romanes's work treats of
+"Mental evolution in man and the origin of human faculties." The
+distinguished psychologist gives a convincing proof in it "that the
+psychological barrier between man and the brute has been overcome."
+Man's power of conceptual thought and of abstraction has been gradually
+evolved from the non-conceptual stages of thought and ideation in the
+nearest related mammals. Man's highest mental powers--reason, speech,
+and conscience--have arisen from the lower stages of the same faculties
+in our primate ancestors (the simiæ and prosimiæ). Man has no single
+mental faculty which is his exclusive prerogative. His whole psychic
+life differs from that of the nearest related mammals only in degree,
+and not in kind; quantitatively, not qualitatively.
+
+I recommend those of my readers who are interested in these momentous
+questions of psychology to study the profound work of Romanes. I am
+completely at one with him and Darwin in almost all their views and
+convictions. Wherever an apparent discrepancy is found between these
+authors and my earlier productions, it is either a case of imperfect
+expression on my part or an unimportant difference in application of
+principle. For the rest, it is characteristic of this "science of
+ideas" that the most eminent philosophers hold entirely antagonistic
+views on its fundamental notions.
+
+
+
+
+CHAPTER VII
+
+PSYCHIC GRADATIONS
+
+    Psychological Unity of Organic Nature--Material Basis of the
+    Soul: Psychoplasm--Scale of Sensation--Scale of Movement--Scale
+    of Reflex Action--Simple and Compound Reflex Action--Reflex
+    Action and Consciousness--Scale of Perception--Unconscious and
+    Conscious Perception--Scale of Memory--Unconscious and Conscious
+    Memory--Association of Perceptions--Instinct--Primary and Secondary
+    Instincts--Scale of Reason--Language--Emotion and Passion--The
+    Will--Freedom of the Will
+
+
+The great progress which psychology has made, with the assistance
+of evolution, in the latter half of the century culminates in the
+recognition of _the psychological unity of the organic world_.
+Comparative psychology, in co-operation with the ontogeny and phylogeny
+of the _psyche_, has enforced the conviction that organic life in all
+its stages, from the simplest unicellular protozoon up to man, springs
+from the same elementary forces of nature, from the physiological
+functions of sensation and movement. The future task of scientific
+psychology, therefore, is not, as it once was, the exclusively
+subjective and introspective analysis of the highly developed mind
+of a philosopher, but the objective, comparative study of the long
+gradation by which man has slowly arisen through a vast series of lower
+animal conditions. This great task of separating the different steps
+in the psychological ladder, and proving their unbroken phylogenetic
+connection, has only been seriously attempted during the last ten
+years, especially in the splendid work of Romanes. We must confine
+ourselves here to a brief discussion of a few of the general questions
+which that gradation has suggested.
+
+All the phenomena of the psychic life are, without exception, bound
+up with certain material changes in the living substance of the body,
+the _protoplasm_. We have given to that part of the protoplasm which
+seems to be the indispensable substratum of psychic life the name
+of _psychoplasm_ (the "soul-substance," in the monistic sense); in
+other words, we do not attribute any peculiar "essence" to it, but
+we consider the _psyche_ to be merely _a collective idea of all the
+psychic functions of protoplasm_. In this sense the "soul" is merely
+a physiological abstraction like "assimilation" or "generation." In
+man and the higher animals, in accordance with the division of labor
+of the organs and tissues, the psychoplasm is a differentiated part of
+the nervous system, the _neuroplasm_ of the ganglionic cells and their
+fibres. In the lower animals, however, which have no special nerves
+and organs of sense, and in the plants, the psychoplasm has not yet
+reached an independent differentiation. Finally, in the unicellular
+protists, the psychoplasm is identified either with the whole of the
+living protoplasm of the simple cell or with a portion of it. In all
+cases, in the lowest as well as the highest stages of the psychological
+hierarchy, a certain chemical composition and a certain physical
+activity of the psychoplasm are indispensable before the "soul" can
+function or act. That is equally true of the elementary psychic
+function of the plasmatic sensation and movement of the protozoa,
+and of the complex functions of the sense-organs and the brain in the
+higher animals and man. The activity of the psychoplasm, which we call
+the "soul," is always connected with metabolism.
+
+All living organisms, without exception, are sensitive; they are
+influenced by the condition of their environment, and react thereon by
+certain modifications in their own structure. Light and heat, gravity
+and electricity, mechanical processes and chemical action in the
+environment, act as _stimuli_ on the sensitive psychoplasm, and effect
+changes in its molecular composition. We may distinguish the following
+five chief stages of this sensibility:
+
+I. At the lowest stage of organization the _whole psychoplasm_, as
+such, is sensitive, and reacts on the stimuli from without; that is the
+case with the lowest protists, with many plants, and with some of the
+most rudimentary animals.
+
+II. At the second stage very simple and undiscriminating _sense-organs_
+begin to appear on the surface of the organism, in the form of
+protoplasmic filaments and pigment spots, the forerunners of the nerves
+of touch and the eyes; these are found in some of the higher protists
+and in many of the lower animals and plants.
+
+III. At the third stage _specific organs_ of sense, each with a
+peculiar adaptation, have arisen by differentiation out of these
+rudimentary processes: there are the chemical instruments of smell
+and taste, and the physical organs of touch, temperature, hearing,
+and sight. The "specific energy" of these sense-organs is not an
+original inherent property of theirs, but has been gained by functional
+adaptation and progressive heredity.
+
+IV. The fourth stage is characterized by the _centralization_ or
+integration of the _nervous system_, and, consequently, of sensation;
+by the association of the previously isolated or localized sensations
+presentations arise, though they still remain unconscious. That is the
+condition of many both of the lower and the higher animals.
+
+V. Finally, at the fifth stage, the highest psychic function,
+_conscious perception_, is developed by the mirroring of the sensations
+in a central part of the nervous system, as we find in man and the
+higher vertebrates, and probably in some of the higher invertebrates,
+notably the articulata.
+
+All living organisms without exception have the faculty of _spontaneous
+movement_, in contradistinction to the rigidity and inertia of
+unorganized substances (_e.g._, crystals); in other words, certain
+changes of place of the particles occur in the living psychoplasm
+from internal causes, which have their source in its own chemical
+composition. These active vital movements are partly discovered by
+direct observation and partly only known indirectly, by inference from
+their effects. We may distinguish five stages of them.
+
+I. At the lowest stage of organic life, in the chromacea, and many
+protophyta and lower metaphyta, we perceive only those _movements of
+growth_ which are common to all organisms. They are usually so slow
+that they cannot be directly observed; they have to be inferred from
+their results--from the change in size and form of the growing organism.
+
+II. Many protists, particularly unicellular algæ of the groups of
+diatomacea and desmidiacea, accomplish a kind of creeping or swimming
+motion by _secretion_, by ejecting a slimy substance at one side.
+
+III. Other organisms which float in water--for instance, many of the
+radiolaria, siphonophora, ktenophora, and others--ascend and descend by
+altering their _specific gravity_, sometimes by osmosis, sometimes by
+the separation or squeezing-out of air.
+
+IV. Many plants, especially the sensitive plants (mimosa) and other
+papilionacea, effect movements of their leaves or other organs by
+_change of pressure_--that is, they alter the strain of the protoplasm,
+and, consequently, its pressure on the enclosing elastic walls of the
+cells.
+
+V. The most important of all organic movements are the _phenomena
+of contraction_--_i.e._, changes of form at the surface of the
+organism, which are dependent on a twofold displacement of their
+elements; they always involve two different conditions or phases
+of motion--contraction and expansion. Four different forms of this
+plasmatic contraction may be enumerated:
+
+    (_a_) Amoeboid movement (in rhizopods, blood-cells,
+    pigment-cells, etc.).
+
+    (_b_) A similar flow of protoplasm within enclosed cells.
+
+    (_c_) Vibratory motion (ciliary movements) in infusoria,
+    spermatozoa, ciliated epithelial cells.
+
+    (_d_) Muscular movement (in most animals).
+
+The elementary psychic activity that arises from the combination of
+sensation and movement is called _reflex_ (in the widest sense),
+reflective function, or _reflex action_. The movement--no matter what
+kind it is--seems in this case to be the immediate result of the
+_stimulus_ which evoked the sensation; it has, on that account, been
+called stimulated motion in its simplest form (in the protists). All
+living protoplasm has this feature of irritability. Any physical or
+chemical change in the environment may, in certain circumstances,
+act as a stimulus on the psychoplasm, and elicit or "release" a
+movement. We shall see later on how this important physical concept of
+"releasing" directly connects the simplest organic reflex actions with
+similar mechanical phenomena of movement in the inorganic world (for
+instance, in the explosion of powder by a spark, or of dynamite by a
+blow). We may distinguish the following seven stages in the scale of
+reflex action:
+
+I. At the lowest stage of organization, in the lowest protists, the
+stimuli of the outer world (heat, light, electricity, etc.) cause in
+the indifferent protoplasm only those indispensable movements of growth
+and nutrition which are common to all organisms, and are absolutely
+necessary for their preservation. That is also the case in most of the
+plants.
+
+II. In the case of many freely moving protists (especially the
+amoeba, the heliozoon, and the rhizopod) the stimuli from without
+produce on every spot of the unprotected surface of the unicellular
+organism external movements which take the form of changes of shape,
+and sometimes changes of place (amoeboid movement, pseudopod
+formation, the extension and withdrawal of what look like feet); these
+indefinite, variable processes of the protoplasm are not yet permanent
+organs. In the same way, general organic irritability takes the form
+of indeterminate reflex action in the sensitive plants and the lowest
+metazoa; in many multicellular organisms the stimuli may be conducted
+from one cell to another, as all the cells are connected by fine fibres.
+
+III. Many protists, especially the more highly developed protozoa,
+produce on their unicellular body two little organs of the simplest
+character--an organ of touch and an organ of movement. Both these
+instruments are direct external projections of protoplasm; the
+stimulus, which alights on the first, is immediately conducted to
+the other by the psychoplasm of the unicellular body, and causes it
+to contract. This phenomenon is particularly easy to observe, and
+even produce experimentally, in many of the stationary infusoria
+(for instance, the _poteriodendron_ among the flagellata, and the
+_vorticella_ among the ciliata). The faintest stimulus that touches the
+extremely sensitive hairs, or _cilia_, at the free end of the cells,
+immediately causes a contraction of a thread-like stalk at the other,
+fixed end. This phenomenon is known as a "simple reflex arch."
+
+IV. These phenomena of the unicellular organism of the infusoria lead
+on to the interesting mechanism of the neuro-muscular cells, which we
+find in the multicellular body of many of the lower metazoa, especially
+in the cnidaria (polyps and corals). Each single neuro-muscular cell
+is a "unicellular reflex organ"; it has on its surface a sensitive
+spot, and a motor muscular fibre inside at the opposite end; the latter
+contracts as soon as the former is stimulated.
+
+V. In other cnidaria, notably in the free swimming medusæ--which are
+closely related to the stationary polyps--the simple neuro-muscular
+cell becomes two different cells, connected by a filament; an external
+_sense-cell_ (in the outer skin) and an internal _muscular cell_ (under
+the skin). In this _bicellular reflex organ_ the one cell is the
+rudimentary organ of sensation, the other of movement; the connecting
+bridge of the psychoplasmic filament conducts the stimulus from one to
+the other.
+
+VI. The most important step in the gradual construction of the reflex
+mechanism is the division into three cells; in the place of the simple
+connecting bridge we spoke of there appears a third independent cell,
+the _soul-cell_, or ganglionic cell; with it appears also a new psychic
+function, _unconscious presentation_, which has its seat in this
+cell. The stimulus is first conducted from the sensitive cell to this
+intermediate presentative or psychic cell, and then issued from this to
+the motor muscular cell as a mandate of movement. These _tricellular
+reflex organs_ are preponderantly developed in the great majority of
+the invertebrates.
+
+VII. Instead of this arrangement we find in most of the vertebrates
+a _quadricellular reflex organ_, two distinct "soul-cells," instead
+of one, being inserted between the sensitive cell and the motor cell.
+The external stimulus, in this case, is first conducted centripetally
+to the sensitive cell (the sensible psychic cell), from this to the
+_will-cell_ (the motor psychic cell), and from this, finally, to the
+contractile muscular cell. When many such reflex organs combine and new
+psychic cells are interposed we have the intricate reflex mechanism of
+man and the higher vertebrates.
+
+The important distinction which we make, in morphology and physiology,
+between unicellular and multicellular organisms holds good for their
+elementary psychic activity, reflex action. In the unicellular
+protists (both the plasmodomous primitive plants, or _protophyta_,
+and the plasmophagous primitive animals, or _protozoa_) the whole
+physical process of reflex action takes place in the protoplasm of
+one single cell; their "cell-soul" seems to be a unifying function
+of the psychoplasm of which the various phases only begin to be seen
+separately when the differentiation of special organs sets in.
+
+The second stage of psychic activity, compound reflex action, begins
+with the cenobitic protists (_v.g._, the volvox and the carchesium).
+The innumerable social cells, which make up this cell-community
+or coenobium, are always more or less connected, often directly
+connected by filamentous bridges of protoplasm. A stimulus that alights
+on one or more cells of the community is communicated to the rest by
+means of the connecting fibres, and may produce a general contraction.
+This connection is found, also, in the tissues of the multicellular
+animals and plants. It was erroneously believed at one time that the
+cells of vegetal tissue were completely isolated from each other, but
+we have now discovered fine filaments of protoplasm throughout, which
+penetrate the thick membranes of the cells, and maintain a material
+and psychological communication between their living plasmic contents.
+That is the explanation of the mimosa: when the tread of the passer-by
+shakes the root of the plant, the stimulus is immediately conveyed to
+all the cells, and causes a general contraction of its tender leaves
+and a drooping of the stems.
+
+An important and universal feature of all reflex phenomena is the
+absence of consciousness. For reasons which we shall give in the tenth
+chapter we only admit the presence of consciousness in man and the
+higher animals, not in plants, the lower animals, and the protists;
+consequently all stimulated movements in the latter must be regarded
+as reflex--that is, all movements which are not _spontaneous_, not the
+outcome of internal causes (impulsive and automatic movements).[14]
+It is different with the higher animals which have developed a
+centralized nervous system and elaborate sense-organs. In these cases
+consciousness has been gradually evolved from the psychic reflex
+activity, and now conscious, voluntary action appears, in opposition to
+the still continuing reflex action below. However, we must distinguish
+two different processes, as we did in the question of instinct--primary
+and secondary reflex action. Primary reflex actions are those which
+have never reached the stage of consciousness in phyletic development,
+and thus preserve the primitive character (by heredity from lower
+animal forms). Secondary reflex actions are those which were conscious,
+voluntary actions in our ancestors, but which afterwards became
+unconscious from habit or the lapse of consciousness. It is impossible
+to draw a hard and fast line in such cases between conscious and
+unconscious psychic function.
+
+Older psychologists (Herbart, for instance) considered "presentation"
+to be the fundamental psychic phenomenon, from which all the others are
+derived. Modern comparative psychology endorses this view in so far as
+it relates to the idea of _unconscious_ presentation; but it considers
+_conscious_ presentation to be a secondary phenomenon of mental life,
+which is entirely wanting in plants and the lower animals, and is
+only developed in the higher animals. Among the many contradictory
+definitions which psychologists have given of "presentation," we think
+the best is that which makes it consist in an internal picture of the
+external object which is given us in sensation--an "idea," in the
+broader sense. We may distinguish the following four stages in the
+rising scale of presentative function:
+
+I. _Cellular presentation._--At the lowest stages we find presentation
+to be a general physiological property of psychoplasm; even in the
+simplest unicellular protist sensations may leave a permanent trace in
+the psychoplasm, and these may be reproduced by memory. In more than
+four thousand kinds of radiolaria, which I have described, every single
+species is distinguished by special, hereditary skeletal structure. The
+construction of this specific, and often highly elaborate, skeleton
+by a cell of the simplest description (generally globular) is only
+intelligible when we attribute the faculty of presentation, and,
+indeed, of a special reproduction of the plastic "feeling of distance,"
+to the constructive protoplasm--as I have pointed out in my _Psychology
+of the Radiolaria_.[15]
+
+II. _Histionic presentation._--In the coenobia or cell-colonies of
+the social protists, and still better in the tissues of plants and
+lower, nerveless animals (sponges, polyps, etc.), we find the second
+stage of unconscious presentation, which consists of the common psychic
+activity of a number of closely connected cells. If a single stimulus
+may, instead of simply spending itself in the reflex movement of an
+organ (the leaf of a plant, for instance, or the arm of a polyp),
+leave a permanent impression, which can be spontaneously reproduced
+later on, we are bound to assume, in explaining the phenomenon, a
+histionic presentation, dependent on the psychoplasm of the associated
+tissue-cells.
+
+III. _Unconscious presentation in the ganglionic cells._--This
+third and higher stage of presentation is the commonest form the
+function takes in the animal world; it seems to be a localization of
+presentation in definite "soul-cells." In its simplest form it appears
+at the sixth stage of reflex action, when the tricellular reflex organ
+arises: the seat of presentation is then the intermediate psychic
+cell, which is interposed between the sensitive cell and the muscular
+cell. With the increasing development of the animal nervous system
+and its progressive differentiation and integration, this unconscious
+presentation also rises to higher stages.
+
+IV. _Conscious presentation in the cerebral cells._--With the highest
+stage of development of the animal organization consciousness arises,
+as a special function of a certain central organ of the nervous
+system. As the presentations are conscious, and as special parts of
+the brain arise for the association of these conscious presentations,
+the organism is qualified for those highest psychic functions which
+we call thought and reflection, intellect and reason. Although the
+tracing of the phyletic barrier between the older, unconscious, and the
+younger, conscious, presentation is extremely difficult, we can affirm,
+with some degree of probability, that the evolution of the latter from
+the former was _polyphyletic_; because we find conscious and rational
+thought, not only in the highest forms of the vertebrate stem (man,
+mammals, birds, and a part of the lower vertebrates), but also in the
+most highly developed representatives of other animal groups (ants
+and other insects, spiders and the higher crabs among the articulata,
+cephalopods among the mollusca).
+
+The evolutionary scale of memory is closely connected with that of
+presentation; this extremely important function of the psychoplasm--the
+condition of all further psychic development--consists essentially
+in the _reproduction of presentations_. The impressions in the
+bioplasm, which the stimulus produced as sensations, and which
+became presentations in remaining, are revived by memory; they pass
+from potentiality to actuality. The latent potential energy of the
+psychoplasm is transformed into kinetic energy. We may distinguish
+four stages in the upward development of memory, corresponding to the
+four stages of presentation.
+
+I. _Cellular memory._--Thirty years ago Ewald Hering showed "memory to
+be a general property of organized matter" in a thoughtful work, and
+indicated the great significance of this function, "to which we owe
+almost all that we are and have." Six years later, in my work on _The
+Perigenesis of the Plastidule, or the Undulatory Origin of the Parts
+of Life: an Experiment in the Mechanical Explanation of Elementary
+Evolutionary Processes_, I developed these ideas, and endeavored
+to base them on the principles of evolution. I have attempted to
+show in that work that unconscious memory is a universal and very
+important function of all _plastidules_; that is, of those hypothetical
+molecules, or groups of molecules, which Naegeli has called _micellae_,
+others _bioplasts_, and so forth. Only _living_ plastidules, as
+individual molecules of the active protoplasm, are reproductive,
+and so gifted with memory; that is the chief difference between the
+organic and inorganic worlds. It might be stated thus: "Heredity is
+the memory of the plastidule, while variability is its comprehension."
+The elementary memory of the unicellular protist is made up of the
+molecular memory of the plastidules or _micellae_, of which its living
+cell-body is constructed. As regards the extraordinary performances
+of unconscious memory in these unicellular protists, nothing could be
+more instructive than the infinitely varied and regular formation of
+their defensive apparatus, their shells and skeletons; in particular,
+the diatomes and cosmaria among the protophytes, and the radiolaria
+and thalamophora among the protozoa, afford an abundance of most
+interesting illustrations. In many thousand species of these protists
+the specific form which is inherited is _relatively constant_, and
+proves the fidelity of their unconscious cellular memory.
+
+II. _Histionic memory._--Equally interesting examples of the second
+stage of memory, the unconscious memory of tissues, are found in the
+heredity of the individual organs of plants and the lower, nerveless
+animals (sponges, etc.). This second stage seems to be _a reproduction
+of the histionic presentations_, that association of cellular
+presentations which sets in with the formation of coenobia in the
+social protists.
+
+III. In the same way we must regard the third stage, the unconscious
+memory of those animals which have a nervous system, as a reproduction
+of the corresponding "unconscious presentations" which are stored up
+in certain ganglionic cells. In most of the lower animals all memory
+is unconscious. Moreover, even in man and the higher animals, to whom
+we must ascribe consciousness, the daily acts of unconscious memory
+are much more numerous and varied than those of the conscious faculty;
+we shall easily convince ourselves of that if we make an impartial
+study of a thousand unconscious acts we perform daily out of habit, and
+without thinking of them, in walking, speaking, writing, eating, and so
+forth.
+
+IV. Conscious memory, which is the work of certain brain-cells in
+man and the higher animals, is an "internal mirroring" of very late
+development, the highest outcome of the same psychic reproduction of
+presentations which were mere unconscious processes in the ganglionic
+cells of our lower animal ancestors.
+
+The concatenation of presentations--usually called the association of
+ideas--also runs through a long scale, from the lowest to the highest
+stages. This, too, is originally and predominantly unconscious
+("instinct"); only in the higher classes of animals does it gradually
+become conscious ("reason"). The psychic results of this "association
+of ideas" are extremely varied; still, a very long, unbroken line of
+gradual development connects the simplest unconscious association of
+the lowest protist with the elaborate conscious chain of ideas of the
+civilized man. The _unity of consciousness_ in man is given as its
+highest consequence (Hume, Condillac). All higher mental activity
+becomes more perfect in proportion as the normal association extends
+to more numerous presentations, and in proportion to the order which
+is imposed on them by the "criticism of pure reason." In dreams,
+where this criticism is absent, the association of the reproduced
+impressions often takes the wildest forms. Even in the work of the
+poetic imagination, which constructs new groups of images by varying
+the association of the impressions received, and in hallucinations,
+etc., they are often most unnaturally arranged, and seem to the
+prosaic observer to be perfectly irrational. This is especially true
+of supernatural "forms of belief," the apparitions of spiritism,
+and the fantastic notions of the transcendental dualist philosophy;
+though it is precisely these _abnormal associations_ of "faith" and of
+"revelation" that have often been deemed the greatest treasures of the
+human mind (cf. chap. xvi.).
+
+The antiquated psychology of the Middle Ages (which, however, still
+numbers many adherents) considered the mental life of man and that
+of the brute to be two entirely different phenomena; the one it
+attributed to "reason," the other to "instinct." In harmony with the
+traditional story of creation, it was assumed that each animal species
+had received a definite, unconscious psychic force from the Creator
+at its formation, and that this instinct of each species was just as
+unchangeable as its bodily structure. Lamarck proved the untenableness
+of this error in 1809 by establishing the theory of Descent, and Darwin
+completely demolished it in 1859. He proved the following important
+theses with the aid of his theory of selection:
+
+1. The instincts of species show individual differences, and are
+just as subject to modification under the law of _adaptation_ as the
+morphological features of their bodily structure.
+
+2. These modifications (generally arising from a change of habits) are
+partly transmitted to offspring by _heredity_, and thus accumulate and
+are accentuated in the course of generations.
+
+3. _Selection_, both artificial and natural, singles out certain of
+these inherited modifications of the psychic activity; it preserves the
+most useful and rejects the least adaptive.
+
+4. The _divergence_ of psychic character which thus arises leads, in
+the course of generations, to the formation of new instincts, just as
+the divergence of morphological character gives rise to new species.
+
+Darwin's theory of instinct is now accepted by most biologists; Romanes
+has treated it so ably, and so greatly expanded it in his distinguished
+work on _Mental Evolution in the Animal World_, that I need merely
+refer to it here. I will only venture the brief statement that, in my
+opinion, there are instincts in _all_ organisms--in all the protists
+and plants as well as in all the animals and in man; though in the
+latter they tend to disappear in proportion as reason makes progress at
+their expense.
+
+The two chief classes of instincts to be differentiated are the
+primary and secondary. Primary instincts are the common lower
+impulses which are unconscious and inherent in the psychoplasm
+from the commencement of organic life; especially the impulses to
+self-preservation (by defence and maintenance) and to the preservation
+of the species (by generation and the care of the young). Both these
+fundamental instincts of organic life, _hunger_ and _love_, sprang
+up originally in perfect unconsciousness, without any co-operation
+of the intellect or reason. It is otherwise with the _secondary_
+instincts. These were due originally to an intelligent adaptation, to
+rational thought and resolution, and to purposive conscious action.
+Gradually, however, they became so automatic that this "other nature"
+acted unconsciously, and, even through the action of heredity, seemed
+to be "innate" in subsequent generations. The consciousness and
+deliberation which originally accompanied these particular instincts
+of the higher animals and man have died away in the course of the
+life of the plastidules (as in "abridged heredity"). The unconscious
+purposive actions of the higher animals (for instance, their mechanical
+instincts) thus come to appear in the light of innate impulses. We have
+to explain in the same way the origin of the "_à priori_ ideas" of man;
+they were originally formed empirically by his predecessors.[16]
+
+In the superficial psychological treatises which ignore the mental
+activity of animals and attribute to man only a "true soul," we
+find him credited also with the exclusive possession of reason and
+consciousness. This is another trivial error (still to be found in many
+a manual, nevertheless) which the comparative psychology of the last
+forty years has entirely dissipated. The higher vertebrates (especially
+those mammals which are most nearly related to man) have just as good a
+title to "reason" as man himself, and within the limits of the animal
+world there is the same long chain of the gradual development of
+reason as in the case of humanity. The difference between the reason
+of a Goethe, a Kant, a Lamarck, or a Darwin, and that of the lowest
+savage, a Veddah, an Akka, a native Australian, or a Patagonian, is
+much greater than the graduated difference between the reason of the
+latter and that of the most "rational" mammals, the anthropoid apes, or
+even the papiomorpha, the dog, or the elephant. This important thesis
+has been convincingly proved by the thoroughly critical comparative
+work of Romanes and others. We shall not, therefore, attempt to cover
+that ground here, nor to enlarge on the distinction between the reason
+and the intellect; as to the meaning and limits of these concepts
+philosophic experts give the most contradictory definitions, as they do
+on so many other fundamental questions of psychology. In general it may
+be said that the process of the formation of concepts, which is common
+to both these cerebral functions, is confined to the narrower circle of
+concrete, proximate associations in the intellect, but reaches out to
+the wider circle of abstract, more comprehensive groups of associations
+in the work of reason. In the long gradation which connects the reflex
+actions and the instincts of the lower animals with the reason of the
+highest, intellect precedes the latter. And there is the fact, of
+great importance to our whole psychological treatise, that even these
+highest of our mental faculties are just as much subject to the laws
+of heredity and adaptation as are their respective organs; Flechsig
+pointed out in 1894 that the "organs of thought," in man and the higher
+mammals, are those parts of the cortex of the brain which lie between
+the four inner sense-centres (cf. chapters x. and xi.).
+
+The higher grade of development of ideas, of intellect and reason,
+which raises man so much above the brute, is intimately connected with
+the rise of language. Still here also we have to recognize a long chain
+of evolution which stretches unbroken from the lowest to the highest
+stages. Speech is no more an exclusive prerogative of man than reason.
+In the wider sense, it is a common feature of all the higher gregarious
+animals, at least of all the articulata and the vertebrates, which live
+in communities or herds; they need it for the purpose of understanding
+each other and communicating their impressions. This is effected either
+by touch or by signs, or by sounds having a definite meaning. The
+song of the bird or of the anthropoid ape (_hylobates_), the bark of
+the dog, the neigh of the horse, the chirp of the cricket, the cry of
+the cicada, are all specimens of animal speech. Only in man, however,
+has that articulate conceptual speech developed which has enabled his
+reason to attain such high achievements. Comparative philology, one
+of the most interesting sciences that has arisen during the century,
+has shown that the numerous elaborate languages of the different
+nations have been slowly and gradually evolved from a few simple
+primitive tongues (Wilhelm Humboldt, Bopp, Schleicher, Steinthal, and
+others). August Schleicher, of Jena, in particular, has proved that
+the historical development of language takes place under the same
+phylogenetic laws as the evolution of other physiological faculties
+and their organs. Romanes (1893) has expanded this proof, and amply
+demonstrated that human speech, also, differs from that of the brute
+only in _degree_ of development, not in essence and kind.
+
+The important group of psychic activities which we embrace under the
+name of "emotion" plays a conspicuous part both in theoretical and
+practical psychology. From our point of view they have a peculiar
+importance from the fact that we clearly see in them the direct
+connection of cerebral functions with other physiological functions
+(the beat of the heart, sense-action, muscular movement, etc.);
+they, therefore, prove the unnatural and untenable character of
+the philosophy which would essentially dissociate psychology from
+physiology. All the external expressions of emotional life which we
+find in man are also present in the higher animals (especially in the
+anthropoid ape and the dog); however varied their development may be,
+they are all derived from the two elementary functions of the _psyche_,
+sensation and motion, and from their combination in reflex action and
+presentation. To the province of sensation, in a wide sense, we must
+attribute the feeling of _like_ and _dislike_ which determines the
+emotion; while the corresponding _desire_ and _aversion_ (love and
+hatred), the effort to attain what is liked and avoid what is disliked,
+belong to the category of movement. "Attraction" and "repulsion"
+seem to be the sources of _will_, that momentous element of the soul
+which determines the character of the individual. The _passions_,
+which play so important a part in the psychic life of man, are but
+intensifications of emotion. Romanes has recently shown that these also
+are common to man and the brute. Even at the lowest stage of organic
+life we find in all the protists those elementary feelings of like
+and dislike, revealing themselves in what are called their _tropisms_,
+in the striving after light and darkness, heat or cold, and in their
+different relations to positive and negative electricity. On the other
+hand, we find at the highest stage of psychic life, in civilized man,
+those finer shades of emotion, of delight and disgust, of love and
+hatred, which are the mainsprings of civilization and the inexhaustible
+sources of poetry. Yet a connecting chain of all conceivable gradations
+unites the most primitive elements of feeling in the psychoplasm of the
+unicellular protist with the highest forms of passion that rule in the
+ganglionic cells of the cortex of the human brain. That the latter are
+absolutely amenable to physical laws was proved long ago by the great
+Spinoza in his famous _Statics of Emotion_.
+
+The notion of _will_ has as many different meanings and definitions
+as most other psychological notions--presentation, soul, mind, and
+so forth. Sometimes will is taken in the widest sense as a _cosmic
+attribute_, as in the "World as will and presentation" of Schopenhauer;
+sometimes it is taken in its narrowest sense as an _anthropological
+attribute_, the exclusive prerogative of man--as Descartes taught, for
+instance, who considered the brute to be a mere machine, without will
+or sensation. In the ordinary use of the term, _will_ is derived from
+the phenomenon of voluntary movement, and is thus regarded as a psychic
+attribute of most animals. But when we examine the will in the light of
+comparative physiology and evolution, we find--as we do in the case of
+sensation--that it is a universal property of living psychoplasm. The
+automatic and the reflex movements which we observe everywhere, even
+in the unicellular protists, seem to be the outcome of inclinations
+which are inseparably connected with the very idea of life. Even in the
+plants and lowest animals these inclinations, or tropisms, seem to be
+the joint outcome of the inclinations of all the combined individual
+cells.
+
+But when the "tricellular reflex organ" arises (page 115), and a third
+independent cell--the "psychic," or "ganglionic," cell--is interposed
+between the sense-cell and the motor cell, we have an independent
+elementary organ of will. In the lower animals, however, this will
+remains _unconscious_. It is only when consciousness arises in the
+higher animals, as the subjective mirror of the objective, though
+internal, processes in the neuroplasm of the psychic cells, that the
+will reaches that highest stage which likens it in character to the
+human will, and which, in the case of man, assumes in common parlance
+the predicate of "liberty." Its free dominion and action become more
+and more deceptive as the muscular system and the sense-organs develop
+with a free and rapid locomotion, entailing a correlative evolution of
+the brain and the organs of thought.
+
+The question of the liberty of the will is the one which has more than
+any other cosmic problem occupied the time of thoughtful humanity,
+the more so that in this case the great philosophic interest of the
+question was enhanced by the association of most momentous consequences
+for practical philosophy--for ethics, education, law, and so forth.
+Emil du Bois-Reymond, who treats it as the seventh and last of his
+"seven cosmic problems," rightly says of the question: "Affecting
+everybody, apparently accessible to everybody, intimately involved in
+the fundamental conditions of human society, vitally connected with
+religious belief, this question has been of immeasurable importance
+in the history of civilization. There is probably no other object
+of thought on which the modern library contains so many dusty folios
+that will never again be opened." The importance of the question is
+also seen in the fact that Kant put it in the same category with the
+questions of the immortality of the soul and belief in God. He called
+these three great questions the indispensable "postulates of practical
+reason," though he had already clearly shown them to have no reality
+whatever in the light of _pure_ reason.
+
+The most remarkable fact in connection with this fierce and confused
+struggle over the freedom of the will is, perhaps, that it has been
+theoretically rejected, not only by the greatest critical philosophers,
+but even by their extreme opponents, and yet it is still affirmed to
+be self-evident by the majority of people. Some of the first teachers
+of the Christian Churches--such as St. Augustine and Calvin--rejected
+the freedom of the will as decisively as the famous leaders of pure
+materialism, Holbach in the eighteenth and Büchner in the nineteenth
+century. Christian theologians deny it, because it is irreconcilable
+with their belief in the omnipotence of God and in predestination. God,
+omnipotent and omniscient, saw and willed all things from eternity--he
+must, consequently, have predetermined the conduct of man. If man, with
+his free will, were to act otherwise than God had ordained, God would
+not be all-mighty and all-knowing. In the same sense Leibnitz, too,
+was an unconditional determinist. The monistic scientists of the last
+century, especially Laplace, defended determinism as a consequence of
+their mechanical view of life.
+
+The great struggle between the determinist and the indeterminist,
+between the opponent and the sustainer of the freedom of the will,
+has ended to-day, after more than two thousand years, completely in
+favor of the determinist. The human will has no more freedom than that
+of the higher animals, from which it differs only in degree, not in
+kind. In the last century the dogma of liberty was fought with general
+philosophic and cosmological arguments. The nineteenth century has
+given us very different weapons for its definitive destruction--the
+powerful weapons which we find in the arsenal of comparative physiology
+and evolution. We now know that each act of the will is as fatally
+determined by the organization of the individual and as dependent on
+the momentary condition of his environment as every other psychic
+activity. The character of the inclination was determined long ago
+by _heredity_ from parents and ancestors; the determination to each
+particular act is an instance of _adaptation_ to the circumstances of
+the moment wherein the strongest motive prevails, according to the laws
+which govern the statics of emotion. Ontogeny teaches us to understand
+the evolution of the will in the individual child. Phylogeny reveals
+to us the historical development of the will within the ranks of our
+vertebrate ancestors.
+
+
+
+
+CHAPTER VIII
+
+THE EMBRYOLOGY OF THE SOUL
+
+    Importance of Ontogeny to Psychology--Development of the
+    Child-Soul--Commencement of Existence of the Individual
+    Soul--The Storing of the Soul--Mythology of the Origin of
+    the Soul--Physiology of the Origin of the Soul--Elementary
+    Processes in Conception--Coalescence of the Ovum and
+    the Spermatozoon--Cell-Love--Heredity of the Soul from
+    Parents and Ancestors--Its Physiological Nature as the
+    Mechanics of the Protoplasm--Blending of Souls (Psychic
+    Amphigony)--Reversion, Psychological Atavism--The Biogenetic
+    Law in Psychology--Palingenetic Repetition and Cenogenetic
+    Modification--Embryonic and Post-Embryonic Psychogeny
+
+
+The human soul--whatever we may hold as to its nature--undergoes
+a continual development throughout the life of the individual.
+This ontogenetic fact is of fundamental importance in our monistic
+psychology, though the "professional" psychologists pay little or no
+attention to it. Since the embryology of the individual is, on Baer's
+principle--and in accordance with the universal belief of modern
+biologists--the "true torch-bearer for all research into the organic
+body," it will afford us a reliable light on the momentous problems of
+its psychic activity.
+
+Although, however, this "embryology of the soul" is so important and
+interesting, it has hitherto met with the consideration it deserves
+only within a very narrow circle. Until recently teachers were almost
+the only ones to occupy themselves with a part of the problem;
+since their avocation compelled them to assist and supervise the
+formation of the psychic activity in the child, they were bound to
+take a theoretical interest, also, in the psychogenetic facts that
+came under their notice. However, these teachers, for the most part,
+both in recent and in earlier times, were dominated by the current
+dualistic psychology--in so far as they reflected at all; and they were
+totally ignorant of the important facts of comparative psychology, and
+unacquainted with the structure and function of the brain. Moreover,
+their observations only extended to children in their school-days, or
+in the years immediately preceding. The remarkable phenomena which
+the individual psychogeny of the child offers in its earliest years,
+and which are the joy and admiration of all thoughtful parents, were
+scarcely ever made the subject of serious scientific research. Wilhelm
+Preyer was the pioneer of this study in his interesting work on _The
+Mind of the Child_ (1881). To obtain a perfectly clear knowledge of the
+matter, however, we must go further back still; we must commence at the
+first appearance of the soul in the impregnated ovum.
+
+The origin of the human individual--body and soul--was still wrapped
+in complete mystery at the beginning of the nineteenth century. Caspar
+Friedrich Wolff had, it is true, discovered the true character of
+embryonic development in 1759, in his _theoria generationis_, and
+proved with the confidence of a critical observer that there is a
+true _epigenesis_--_i.e._, a series of very remarkable formative
+processes--in the evolution of the foetus from the simple ovum. But
+the physiologists of the time, with the famous Albert Haller at their
+head, flatly refused to entertain these empirical truths, which may be
+directly proved by microscopic observation, and clung to the old dogma
+of "preformation." This theory assumed that in the human ovum--and in
+the egg of all other animals--the organism was already present, or
+"preformed," in all its parts; the "evolution" of the embryo consisted
+literally in an "unfolding" (_evolutio_) of the folded organs. One
+curious consequence of this error was the theory of _scatulation_,
+which we have mentioned on p. 55; since the ovary had to be admitted to
+be present in the embryo of the woman, it was also necessary to suppose
+that the germs of the next generation were already formed in it, and
+so on _in infinitum_. Opposed to this dogma of the "Ovulists" was
+the equally erroneous notion of the "Animalculists"; the latter held
+that the germ was not really in the female ovum, but in the paternal
+element, and that the store of succeeding generations was to be sought
+in the spermatozoa.
+
+Leibnitz consistently applied this theory of scatulation to the human
+soul; he denied that either soul or body had a real development
+(_epigenesis_), and said in his _Theodicy_: "Thus I consider that the
+souls which are destined one day to become human exist in the seed,
+like those of other species; that they have existed in our ancestors
+as far back as Adam--that is, since the beginning of the world--in
+the forms of organized bodies." Similar notions prevailed in biology
+and philosophy until the third decade of the present century, when
+the reform of embryology by Baer gave them their death blow. In the
+province of psychology, however, they still find many adherents; they
+form one group of the many curious mystical ideas which give us a
+living illustration of the ontogeny of the soul.
+
+The more accurate knowledge which we have recently obtained, through
+comparative ethnology, of the various forms of myths of ancient and
+modern uncivilized races, is also of great interest in psychogeny.
+Still, it would take us too far from our purpose if we were to enter
+into it with any fulness here; we must refer the reader to Adalbert
+Svoboda's excellent work on _Forms of Faith_ (1897). In respect of
+their scientific and poetical contents, we may arrange all pertinent
+_psychogenetic myths_ in the following five groups:
+
+I. The myth of transmigration.--The soul lived formerly in the body of
+another animal, and passed from this into a human body. The Egyptian
+priests, for instance, taught that the human soul wandered through all
+the species of animals after the death of the body, returning to a
+human frame after three thousand years of transmigration.
+
+II. The myth of the in-planting of the soul.--The soul existed
+independently in another place--a psychogenetic store, as it were (in a
+kind of embryonic slumber or latent life); it was taken out by a bird
+(sometimes represented as an eagle, generally as a white stork), and
+implanted in the human body.
+
+III. The myth of the creation of the soul.--God creates the souls,
+and keeps them stored--sometimes in a pond (living in the form of
+_plankton_), according to other myths in a tree (where they are
+conceived as the fruit of a phanerogam); the Creator takes them from
+the pond or tree, and inserts them in the human germ during the act of
+conception.
+
+IV. The myth of the scatulation of the soul (the theory of Leibnitz
+which we have given above).
+
+V. The myth of the division of the soul (the theory of Rudolph Wagner
+[1855] and of other physiologists).--In the act of procreation a
+portion is detached from both the (immaterial) souls of the parents;
+the maternal contribution passes in the ovum, the paternal in the
+spermatozoa; when these two germinal cells coalesce, the two psychic
+fragments that accompany them also combine to form a new (immaterial)
+soul.
+
+Although the poetic fancies we have mentioned as to the origin of
+the individual human soul are still widely accepted, their purely
+mythological character is now firmly established. The deeply
+interesting and remarkable research which has been made in the course
+of the last twenty-five years into the more minute processes of the
+impregnation and germination of the ovum has made it clear that these
+mysterious phenomena belong entirely to the province of cellular
+physiology (cf. p. 48). Both the female element, the ovum, and the male
+fertilizing body, the sperma or spermatozoa, are _simple cells_. These
+living cells possess a certain sum of physiological properties to which
+we give the title of the "cell-soul," just as we do in the permanently
+unicellular protist (see p. 48). Both germinal cells have the faculty
+of movement and sensation. The young ovum, or egg-cell, moves after
+the manner of an amoeba; the minute spermatozoa, of which there are
+millions in every drop of the seminal fluid, are ciliated cells, and
+swim about as freely in the sperm, by means of their lashes or _cilia_,
+as the ordinary ciliated infusoria (the flagellata).
+
+When the two cells meet as a result of copulation, or when they are
+brought into contact through artificial fertilization (in the fishes,
+for instance), they attract each other and become firmly attached. The
+main cause of this cellular attraction is a chemical sensitive action
+of the protoplasm, allied to smell or taste, which we call "erotic
+chemicotropism"; it may also be correctly (both in the chemical and
+the romantic sense) termed "cellular affinity" or "sexual cell-love."
+A number of the ciliated cells in the sperm swim rapidly towards the
+stationary egg-cell and seek to penetrate into it. As Hertwig showed in
+1875, as a rule only one of the suitors is fortunate enough to reach
+the desired goal. As soon as this favored spermatozoon has pierced
+into the body of the ovum with its head (the nucleus of the cell), a
+thin mucous layer is detached from the ovum which prevents the further
+entrance of spermatozoa. The formation of this protective membrane
+was only prevented when Hertwig kept the ovum stiff with cold by
+lowering the temperature, or benumbed it with narcotics (chloroform,
+morphia, nicotine, etc.); then there was "super-impregnation" or
+"poly-spermy"--a number of sperm-threads pierced into the body of
+the unconscious ovum. This remarkable fact proved that there is a
+low degree of "cellular instinct" (or, at least, of specific, lively
+sensation) in the sexual cells just as effectively as do the important
+phenomena that immediately follow in their interior. Both nuclei--that
+of the ovum and of the spermatozoon--attract each other, approach, and,
+on contact, completely fuse together. Thus from the impregnated ovum
+arises the important new cell which we call the "stem-cell" (_cytula_),
+from the repeated segmentation of which the whole polycellular organism
+is evolved.
+
+The psychological information which is afforded by these remarkable
+facts of impregnation, which have only been properly observed
+during the last twenty-five years, is supremely important; its vast
+significance has hitherto been very far from appreciated. We shall
+condense the main conclusions of research in the following five theses:
+
+I. Each human individual, like every other higher animal, is a single
+simple cell at the commencement of his existence.
+
+II. This "stem-cell" (cytula) is formed in the same manner in all
+cases--that is, by the blending or copulation of two separate cells of
+diverse origin, the female ovum and the male spermatozoon.
+
+III. Each of these sexual cells has its own "cell-soul"--that is, each
+is distinguished by a peculiar form of sensation and movement.
+
+IV. At the moment of conception or impregnation, not only the
+protoplasm and the nuclei of the two sexual cells coalesce, but also
+their "cell-souls"; in other words, the potential energies which are
+latent in both, and inseparable from the matter of the protoplasm,
+unite for the formation of a new potential energy, the "germ-soul" of
+the newly constructed stem-cell.
+
+V. Consequently each personality owes his bodily and spiritual
+qualities to both parents; by heredity the nucleus of the ovum
+contributes a portion of the maternal features, while the nucleus of
+the spermatozoon brings a part of the father's characteristics.
+
+By these empirical facts of conception, moreover, the further fact of
+extreme importance is established, that every man, like every other
+animal, _has a beginning of existence_; the complete copulation of
+the two sexual cell-nuclei marks the precise moment when not only the
+body, but also the "soul," of the new stem-cell makes its appearance.
+This fact suffices of itself to destroy the myth of the immortality
+of the soul, to which we shall return later on. It suffices, too, for
+the destruction of the still prevalent superstition that man owes
+his personal existence to the favor of God. Its origin is rather to
+be attributed solely to the "eros" of his parents, to that powerful
+impulse that is common to all polycellular animals and plants,
+and leads to their nuptial union. But the essential point in this
+physiological process is not the "embrace," as was formerly supposed,
+or the amorousness connected therewith; it is simply the introduction
+of the spermatozoa into the vagina. This is the sole means, in the
+land-dwelling animals, by which the fertilizing element can reach the
+released ova (which usually takes place in the uterus in man). In the
+case of the lower aquatic animals (fishes, mussels, medusæ, etc.) the
+mature sexual elements on both sides are simply discharged into the
+water, and their union is let to chance; they have no real copulation,
+and so they show none of those higher psychic "erotic" functions which
+play so conspicuous a part in the life of the higher animals. Hence
+it is, also, that all the lower, non-copulating animals are wanting
+in those interesting organs which Darwin has called "secondary sexual
+characters," and which are the outcome of sexual selection: such are
+the beard of man, the antlers of the stag, the beautiful plumage of
+the bird of paradise and of so many other birds, together with other
+distinctions of the male which are absent in the female.
+
+Among the above theses as to the physiology of conception the
+inheritance of the psychic qualities of the two parents is of
+particular importance for psychological purposes. It is well known that
+every child inherits from both his parents peculiarities of character,
+temperament, talent, acuteness of sense, and strength of will. It
+is equally well known that even psychic qualities are often (if not
+always) transmitted from grandparents by heredity--often, in fact,
+a man resembles his grandparents more than his parents in certain
+respects; and that is true both of bodily and mental features. All
+the chief laws of heredity which I first formulated in my _General
+Morphology_, and popularized in my _Natural History of Creation_, are
+just as valid and universal in their application to psychic phenomena
+as to bodily structure--in fact, they are frequently more striking and
+conspicuous in the former than in the latter.
+
+However, the great province of heredity, to the inestimable importance
+of which Darwin first opened our eyes in 1859, is thickly beset with
+obscure problems and physiological difficulties. We dare not claim,
+even after forty years of research, that all its aspects are clear
+to us. Yet we have done so much that we can confidently speak of
+heredity as a _physiological function_ of the organism, which is
+directly connected with the faculty of generation; and we must reduce
+it, like all other vital phenomena, to exclusively physical and
+chemical processes, to the _mechanics of the protoplasm_. We now know
+accurately enough the process of impregnation itself; we know that in
+it the nucleus of the spermatozoon contributes the qualities of the
+male parent, and the nucleus of the ovum gives the qualities of the
+mother, to the newly born stem-cell. The blending of the two nuclei is
+the "physiological moment" of heredity; by it the personal features of
+both body and soul are transmitted to the new individual. These facts
+of ontogeny are beyond the explanation of the dualistic and mystic
+psychology which still prevails in the schools; whereas they find a
+perfectly simple interpretation in our monistic philosophy.
+
+The physiological fact which is most material for a correct appreciation
+of individual psychogeny is the _continuity_ of the _psyche_ through
+the rise and fall of generations. A new individual comes into
+existence at the moment of conception; yet it is not an independent
+entity, either in respect of its mental or its bodily features, but
+merely the product of the blending of the two parental factors, the
+maternal egg-cell and paternal sperm-cell. The cell-souls of these
+two sexual cells combine in the act of conception for the formation
+of a new cell-soul, just as truly as the two cell-nuclei, which are
+the material vehicles of this psychic potential energy, unite to form
+a new nucleus. As we now see that the individuals of one and the same
+species--even sisters born of the same parents--always show certain
+differences, however slight, we must assume that these variations
+were already present in the chemical plasmatic constitution of the
+generative cells themselves.[17]
+
+These facts alone would suffice to explain the infinite variety of
+individual features, of soul and of bodily form, that we find in the
+organic world. As an extreme, but one-sided, consequence of them, there
+is the theory of Weismann, which considers the _amphimixis_, or the
+blending of the germ-plasm in sexual generation, to be the universal
+and the sole cause of individual variability. This exclusive theory,
+which is connected with his theory of the continuity of the germ-plasm,
+is, in my opinion, an exaggeration. I am convinced, on the contrary,
+that the great laws of _progressive heredity_ and of the correlative
+_functional adaptation_ apply to the soul as well as to the body. The
+new characteristics which the individual has acquired during life may
+react to some extent on the molecular texture of the germ-plasm in
+the egg-cell and sperm-cell, and may thus be transferred to the next
+generation by heredity in certain conditions (naturally, only in the
+form of latent energy).
+
+Although in the soul-blending at the moment of conception only
+the latent forces of the two parent souls are transmitted by the
+coalescence of the erotic cell-nuclei, still it is possible that the
+hereditary psychic influence of earlier, and sometimes very much
+older, generations may be communicated at the same time. For the laws
+of _latent heredity_ or atavism apply to the soul just as validly as
+to the anatomical organization. We find these remarkable phenomena of
+reversion in a very simple and instructive form in the alternation of
+generations of the polyps and medusæ. Here we see two very different
+generations alternate so regularly that the first resembles the third,
+fifth, and so on; while the second (very different from the preceding)
+is like the fourth, sixth, etc. (_Natural History of Creation_). We do
+not find such alternation of generations in man and the higher animals
+and plants, in which, owing to continuous heredity, each generation
+resembles the next; nevertheless, even in these cases we often meet
+with phenomena of reversion, which must be reduced to the same law of
+latent heredity.
+
+Eminent men often take more after their grandparents than their parents
+even in the finer shades of psychic activity--in the possession of
+certain artistic talents or inclinations, in force of character, and
+in warmth of temperament; not infrequently there is a striking feature
+which neither parents nor grandparents possessed, but which may be
+traced a long way back to an older branch of the family. Even in
+these remarkable cases of atavism the same laws of heredity apply to
+the _psyche_ and to the physiognomy, to the personal quality of the
+sense-organs, muscles, skeleton, and other parts of the body. We can
+trace them most clearly in the reigning dynasties and in old families
+of the nobility, whose conspicuous share in the life of the State has
+given occasion to a more careful historical picture of the individuals
+in the chain of generations--for instance, in the Hohenzollerns, the
+princes of Orange, the Bourbons, etc., and in the Roman Cæsars.
+
+The causal-nexus of _biontic_ (individual) and _phyletic_ (historical)
+evolution, which I gave in my _General Morphology_ as the supreme law
+at the root of all biogenetic research, has a universal application to
+psychology no less than to morphology. I have fully treated the special
+importance which it has with regard to man, in both respects, in the
+first chapter of my _Anthropogeny_. In man, as in all other organisms,
+"the embryonic development is an epitome of the historical development
+of the species. This condensed and abbreviated recapitulation is the
+more complete in proportion as the original _epitomized development_
+(_palingenesis_) is preserved by a constant heredity; on the other
+hand, it falls off from completeness in proportion as the later
+_disturbing development_ (_cenogenesis_) is accentuated by varying
+adaptation."
+
+While we apply this law to the evolution of the soul, we must lay
+special stress on the injunction to keep _both_ sides of it critically
+before us. For, in the case of man, just as in all the higher animals
+and plants, such appreciable perturbations of type (or _cenogeneses_)
+have taken place during the millions of years of development that
+the original simple idea of _palingenesis_, or "epitome of history,"
+has been greatly disturbed and altered. While, on the one side, the
+_palingenetic_ recapitulation is preserved by the laws of like-time
+and like-place heredity, it is subject to an essential _cenogenetic_
+change, on the other hand, by the laws of abbreviated and simplified
+heredity. That is clearly seen in the embryonic evolution of the
+psychic organs, the nervous system, the muscles, and the sense-organs.
+But it applies in just the same manner to the psychic functions, which
+are absolutely dependent on the normal construction of these organs.
+Their evolution is subject to great cenogenetic modification in man
+and all other viviparous animals, precisely because the complete
+development of the embryo occupies a longer time within the body of
+the mother. But we have to distinguish two periods of individual
+psychogeny: (1) the embryonic, and (2) the post-embryonic development
+of the soul.
+
+I. _Embryonic Psychogeny._--The human foetus, or embryo, normally
+takes nine months (or two hundred and seventy days) to develop in
+the uterus. During this time it is entirely cut off from the outer
+world, and protected, not only by the thick muscular wall of the womb,
+but also by the special foetal membranes (_embryolemmata_) which
+are common to all the three higher classes of vertebrates--reptiles,
+birds, and mammals. In all the classes of amniotes these membranes
+(the _amnion_ and the _serolemma_) develop in just the same fashion.
+They represent the protective arrangements which were acquired by
+the earliest reptiles (_proreptilia_), the common parents of all the
+amniotes, in the Permian period (towards the end of the palæozoic
+age), when these higher vertebrates accustomed themselves to live on
+land and breathe the atmosphere. Their ancestors, the amphibia of the
+Carboniferous period, still lived and breathed in the water, like their
+earlier predecessors, the fishes.
+
+In the case of these older and lower vertebrates that lived in the
+water, the embryonic development had the palingenetic character in
+a still higher degree, as is the case in most of the fishes and
+amphibia of the present day. The familiar tadpole and the larva of
+the salamander or the frog still preserve the structure of their
+fish-ancestors in the first part of their life in the water; they
+resemble them, likewise, in their habits of life, in breathing by
+gills, in the action of their sense-organs, and in other psychic
+organs. Then, when the interesting metamorphosis of the swimming
+tadpole takes place, and when it adapts itself to a land-life, the
+fish-like body changes into that of a four-footed, crawling amphibium;
+instead of the gill-breathing in the water comes an exclusive
+breathing of the atmosphere by means of lungs, and, with the changed
+habits of life, even the psychic apparatus, the nervous system, and
+the sense-organs reach a higher degree of construction. If we could
+completely follow the psychogeny of the tadpole from beginning to end,
+we should be able to apply the biogenetic law in many ways to its
+psychic evolution. For it develops in direct communication with the
+changing conditions of the outer world, and so must quickly adapt its
+sensation and movement to these. The swimming tadpole has not only the
+structure but the habits of life of a fish, and only acquires those of
+a frog in its metamorphosis.
+
+It is different with man and all the other amniotes; their embryo is
+entirely withdrawn from the direct influence of the outer world, and
+cut off from any reciprocal action therewith, by enclosure in its
+protective membranes. Besides, the special care of the young on the
+part of the amniotes gives their embryo much more favorable conditions
+for the cenogenetic abbreviation of the palingenetic evolution. There
+is, in the first place, the excellent arrangement for the nourishment
+of the embryo; in the reptiles, birds, and monotremes (the oviparous
+mammals) it is effected by the great yellow nutritive yelk, which is
+associated with the egg; in the rest of the mammals (the marsupials and
+placentals) it is effected by the mother's blood, which is conducted to
+the foetus by the blood-vessels of the yelk-sac and the allantois.
+In the case of the most highly developed placentals this elaborate
+nutritive arrangement has reached the highest degree of perfection by
+the construction of a placenta; hence in these classes the embryo is
+fully developed before birth. But its soul remains during all this time
+in a state of embryonic slumber, a state of repose which Preyer has
+justly compared to the hibernation of animals. We have a similar long
+sleep in the chrysalis stage of those insects which undergo a complete
+metamorphosis--butterflies, bees, flies, beetles, and so forth. This
+sleep of the pupa, during which the most important formations of
+organs and tissues take place, is the more interesting from the fact
+that the preceding condition of the free larva (caterpillar, grub, or
+maggot) included a highly developed psychic activity, and that this is,
+significantly, lower than the stage which is seen afterwards (when the
+chrysalis sleep is over) in the perfect, winged, sexually mature insect.
+
+Man's psychic activity, like that of most of the higher animals, runs
+through a long series of stages of development during the individual
+life. We may single out the five following as the most important of
+them:
+
+I. The soul of the new-born infant up to the birth of self-consciousness
+and the learning of speech.
+
+II. The soul of the boy or girl up to puberty (_i.e._, until the
+awakening of the sexual instinct).
+
+III. The soul of the youth or maiden up to the time of sexual
+intercourse (the "idealist" period).
+
+IV. The soul of the grown man and the mature woman (the period of
+full maturity and of the founding of families, lasting until about
+the sixtieth year for the man and the fiftieth for the woman--until
+_involution_ sets in).
+
+V. The soul of the old man or woman (the period of degeneration).
+
+Man's psychic life runs the same evolution--upward progress, full
+maturity, and downward degeneration--as every other vital activity in
+his organization.
+
+
+
+
+CHAPTER IX
+
+THE PHYLOGENY OF THE SOUL
+
+    Gradual Historical Evolution of the Human Soul from the Animal
+    Soul--Methods of Phylogenetic Psychology--Four Chief Stages in
+    the Phylogeny of the Soul: I. The Cell-Soul (Cytopsyche) of the
+    Protist (Infusoria, Ova, etc.): Cellular Psychology; II. The Soul
+    of a Colony of Cells, or the Cenobitic Soul (Coenopsyche):
+    Psychology of the Morula and Blastula; III. The Soul of the Tissue
+    (Histopsyche): Its Twofold Nature: The Soul of the Plant: The Soul
+    of the Lower, Nerveless Animal: Double Soul of the Siphonophora
+    (Personal and Kormal Soul); IV. The Nerve-Soul (Neuropsyche)
+    of the Higher Animal--Three Sections of its Psychic Apparatus:
+    Sense-Organs, Muscles, and Nerves--Typical Formation of the
+    Nerve-Centre in the Various Groups of Animals--Psychic Organ of the
+    Vertebrate: the Brain and the Spinal Cord--Phylogeny of the Mammal
+    Soul
+
+
+The theory of descent, combined with anthropological research, has
+convinced us of the descent of our human organism from a long series
+of animal ancestors by a slow and gradual transformation occupying
+many millions of years. Since, then, we cannot dissever man's psychic
+life from the rest of his vital functions--we are rather forced to a
+conviction of the natural evolution of our whole body and mind--it
+becomes one of the main tasks of the modern monistic psychology to
+trace the stages of the historical development of the soul of man from
+the soul of the brute. Our "phylogeny of the soul" seeks to attain this
+object; it may also, as a branch of general psychology, be called
+_phylogenetic_ psychology, or, in contradistinction to _biontic_
+(individual), _phyletic psychogeny_. And, although this new science has
+scarcely been taken up in earnest yet, and most of the "professional"
+psychologists deny its very right to existence, we must claim for it
+the utmost importance and the deepest interest. For, in our opinion, it
+is its special province to solve for us the great enigma of the nature
+and origin of the human soul.
+
+The methods and paths which will lead us to the remote goal of a
+complete phylogenetic psychology--a goal that is still buried in the
+mists of the future, and almost imperceptible to many--do not differ
+from those of other branches of evolutionary research. Comparative
+anatomy, physiology, and ontogeny are of the first importance. Much
+support is given also by palæontology, for the order in which the
+fossil remains of the various classes of vertebrates succeed each other
+in the course of organic evolution reveals to us, to some extent,
+the gradual growth of their psychic power as well as their phyletic
+connection. We must admit that we are here, as we are in every branch
+of phylogenetic research, driven to the construction of a number of
+hypotheses in order to fill up the considerable lacunæ of empirical
+phylogeny. Yet these hypotheses cast so clear and significant a light
+on the chief stages of historical development that we are afforded a
+most gratifying insight into their entire course.
+
+The comparative psychology of man and the higher animals enables us
+to learn from the highest group of the placentals, the primates, the
+long strides by which the human soul has advanced beyond the _psyche_
+of the anthropoid ape. The phylogeny of the mammals and of the lower
+vertebrates acquaints us with the long series of the earlier ancestors
+of the primates which have arisen within this stem since the Silurian
+age. All these vertebrates agree in the structure and development of
+their characteristic psychic organ--the spinal cord. We learn from
+the comparative anatomy of the vermalia that this spinal cord has
+been evolved from a dorsal _acroganglion_, or vertical brain, of an
+invertebrate ancestor. We learn, further, from comparative ontogeny
+that this simple psychic organ has been evolved from the stratum of
+cells in the outer germinal layer, the ectoderm, of the platodes. In
+these earliest flat-worms, which have no specialized nervous system,
+the outer skin-covering serves as a general sensitive and psychic
+organ. Finally, comparative embryology teaches us that these simple
+metazoa have arisen by gastrulation from blastæades, from hollow
+spheres, the wall of which is merely one simple layer of cells, the
+_blastoderm_; and the same science, with the aid of the biogenetic law,
+explains how these protozoic coenobia originally sprang from the
+simplest unicellular organisms.
+
+On a critical study of these different embryonic formations, the
+evolution of which from each other we can directly observe under the
+microscope, we arrive, by means of the great law of biogeny, at a
+series of most important conclusions as to the chief stages in the
+development of our psychic life. We may distinguish eight of these to
+begin with:
+
+I. Unicellular protozoa with a simple cell-soul: the infusoria.
+
+II. Multicellular protozoa with a communal soul: the catallacta.
+
+III. The earliest metazoa with an epithelial soul: the platodes.
+
+IV. Invertebrate ancestors with a simple vertical brain: the vermalia.
+
+V. Vertebrates without skull or brain, with a simple spinal cord: the
+acrania.
+
+VI. Animals with skull and brain (of five vesicles): the craniota.
+
+VII. Mammals with predominant development of the cortex of the brain:
+the placentals.
+
+VIII. The higher anthropoid apes and man, with organs of thought (in
+the cerebrum): the anthropomorpha.
+
+Among these eight stages in the development of the human soul we may
+further distinguish more or less clearly a number of subordinate
+stages. Naturally, however, in reconstructing them we have to fall
+back on the same defective evidence of empirical psychology which the
+comparative anatomy and physiology of the actual fauna affords us. As
+the craniote animals of the sixth stage--and these are true fishes--are
+already found fossilized in the Silurian system, we are forced to
+assume that the five preceding series of ancestors (which were
+incapable of fossilization) were evolved in an earlier, pre-Silurian
+age.
+
+I. _The cell-soul_ (_or cytopsyche_): first stage of phyletic
+psychogenesis.--The earliest ancestors of man and all other animals
+were unicellular protozoa. This fundamental hypothesis of rational
+phylogeny is based, in virtue of the phylogenetic law, on the
+familiar embryological fact that every man, like every other metazoon
+(_i.e._, every multicellular organism with tissues), begins his
+personal existence as a simple cell, the stem-cell (_cytula_), or the
+impregnated egg-cell (see p. 63). As this cell has a "soul" from the
+commencement, so had also the corresponding unicellular _ancestral
+forms_, which were represented in the oldest series of man's ancestors
+by a number of different protozoa.
+
+We learn the character of the psychic activity of these unicellular
+organisms from the comparative physiology of the protists of to-day.
+Close observation and careful experiment have opened out to us in this
+respect, in the second half of the nineteenth century, a new world of
+the most interesting phenomena. The best description of them was given
+by Max Verworn in his thoughtful work, based on original research,
+_Psycho-physiological Studies of the Protists_. The work includes also
+the few earlier observations of the "psychic life of the protist."
+Verworn came to the firm conclusion that the psychic processes are
+unconscious in all the protists, that the phenomena of sensation
+and movement coincide with the molecular vital processes in their
+protoplasm, and that their ultimate causes are to be sought in the
+properties of the protoplasmic molecules (the _plastidules_). "Hence
+the psychic phenomena of the protists form a bridge that connects the
+chemical processes of the inorganic world with the psychic life of
+the highest animals; they represent the germ of the highest psychic
+phenomena of the metazoa and of man."
+
+The careful observations and many experiments of Verworn, together
+with those of Wilhelm Engelmann, Wilhelm Preyer, Richard Hertwig, and
+other more recent students of the protists, afford conclusive evidence
+for my "theory of the cell-soul" (1866). On the strength of several
+years of study of different kinds of protists, especially rhizopods and
+infusoria, I published a theory thirty-three years ago to the effect
+that every living cell has psychic properties, and that the psychic
+life of the multicellular animals and plants is merely the sum total of
+the psychic functions of the cells which build up their structure. In
+the lower groups (in algæ and sponges, for instance) _all_ the cells of
+the body have an equal share in it (or with very slight differences);
+in the higher groups, in harmony with the law of the "division of
+labor," only a select portion of them are involved--the "soul-cells."
+The important consequences of this "cellular psychology" were partly
+treated in my work on _The Perigenesis of the Plastidule_ (1876),
+and partly in my speech at Munich, in 1877, on "Modern Evolution in
+Relation to the Whole of Science." A more popular presentation of
+them is to be found in my two Vienna papers (1878) on "The Origin and
+Development of the Sense-Organs" and on "Cell-Souls and Soul-Cells."
+
+Moreover, the cell-soul, even within the limits of the protist world,
+presents a long series of stages of development, from the most simple
+and primitive to a comparatively elaborate activity. In the earliest
+and simplest protists the faculty of sensation and movement is equally
+distributed over the entire protoplasm of the homogeneous morsel; in
+the higher forms certain "cell-instruments," or _organella_, appear,
+as their physiological organs. Motor cell-parts of that character are
+found in the pseudopodia of the rhizopods, and the vibrating hairs,
+lashes, or cilia of the infusoria. The cell-nucleus, which is wanting
+in the earlier and lower protists, is considered to be an internal
+central organ of the cell-life. It is especially noteworthy, from a
+physiologico-chemical point of view, that the very earliest protists
+were plasmodomous, with plant-like nutrition--hence _protophyta_, or
+primitive plants; from these came as a secondary stage, by metasitism,
+the first plasmophagi, with animal nutrition--the _protozoa_, or
+primitive animals.[18] This metasitism, or circulation of nutritive
+matter, implies an important psychological advance; with it began the
+development of those characteristic properties of the animal soul which
+are wanting in the plant.
+
+We find the highest development of the animal cell-soul in the class
+of ciliata, or ciliated infusoria. When we compare their activity
+with the corresponding psychic life of the higher, multicellular
+animals, we find scarcely any psychological difference; the sensitive
+and motor _organella_ of these protozoa seem to accomplish the same
+as the sense-organs, nerves, and muscles of the metazoa. Indeed, we
+have found in the great cell-nucleus (_meganucleus_) of the infusoria
+a central organ of psychic activity, which plays much the same part
+in their unicellular organism as the brain does in the psychic life
+of higher animals. However, it is very difficult to determine how far
+this comparison is justified; the views of experts diverge considerably
+over the matter. Some take all spontaneous bodily movement in them to
+be automatic, or impulsive, and all stimulated movement to be reflex;
+others are convinced that such movements are partly voluntary and
+intentional. The latter would attribute to the infusoria a certain
+degree of consciousness, and even self-consciousness; but this is
+rejected by the others. However that very difficult question may be
+settled, it does not alter the fact that these unicellular protozoa
+give proof of the possession of a highly developed "cell-soul," which
+is of great interest for a correct decision as to the _psyche_ of our
+earliest unicellular ancestors.
+
+II. _The communal or cenobitic soul_ (_coenopsyche_): second stage of
+phyletic psychogenesis.--Individual development begins, in man and in
+all other multicellular animals, with the repeated segmentation of one
+simple cell. This _stem-cell_, the impregnated ovum, divides first into
+two daughter cells, by a process of ordinary indirect segmentation;
+as the process is repeated there arise (by equal division of the egg)
+successively four, eight, sixteen, thirty-two, sixty-four such new
+cells, or "blastomeres." Usually (that is, in the case of the majority
+of animals) an irregular enlargement sooner or later takes the place
+of this original regular division of cells. But the result is the same
+in all cases--the formation of a (generally spherical) cluster of
+heterogeneous (originally homogeneous) cells. This stage is called the
+_morula_ ("mulberry," which it somewhat resembles in shape). Then, as
+a rule, a fluid gathers in the interior of this aggregate of cells; it
+changes into a spherical vesicle; all the cells go to its surface, and
+arrange themselves in one simple layer--the _blastoderm_. The hollow
+sphere which is thus formed is the important stage of the "germinal
+vesicle," the _blastula_, or blastosphere.
+
+The psychological phenomena which we directly observe in the formation
+of the blastula are partly sensations, partly movements, of this
+community of cells. The movements may be divided into two groups: (1)
+the inner movements, which are always repeated in substantially the
+same manner in the process of ordinary (indirect) segmentation of
+cells (formation of the axis of the nucleus, mitosis, karyokinesis,
+etc.); (2) the outer movements, which are seen in the regular change of
+position of the social cells and their grouping for the construction
+of the blastoderm. We assume that these movements are hereditary and
+unconscious, because they are always determined in the same fashion by
+heredity from the earlier protist ancestors. The sensations also fall
+into two groups: (1) the sensations of the individual cells, which
+reveal themselves in the assertion of their individual independence and
+their relation to neighboring cells (with which they are in contact,
+and partly in direct combination, by means of protoplasmic fibres); (2)
+the common sensation of the entire community of cells, which is seen in
+the individual formation of the _blastula_ as a hollow vesicle.
+
+The causal interpretation of the formation of the blastula is given us
+by the biogenetic law, which explains the phenomena we directly observe
+to be the outcome of heredity, and relates them to corresponding
+historical processes which took place long ago in the origin of the
+earliest protist-coenobia, the blastæads. But we get a physiological
+and psychological insight into these important phenomena of the
+earliest cell-communities by observation and experiment on their modern
+representatives. Such permanent cell-communities or colonies are still
+found in great numbers both among the plasmodomous primitive plants
+(for instance, the paulotomacea, diatomacea, volvocinæ, etc.) and the
+plasmophagous primitive animals (the infusoria and rhizopods). In
+all these coenobia we can easily distinguish two different grades
+of psychic activity: (1) the cell-soul of the individual cells (the
+"elementary organisms") and (2) the communal soul of the entire colony.
+
+III. _The tissue-soul_ (_histopsyche_): third stage of phyletic
+psychogenesis.--In all multicellular, tissue-forming plants
+(_metaphyta_) and in the lowest, nerveless classes of tissue-forming
+animals (_metazoa_) we have to distinguish two different forms of
+psychic activity--namely: (1) the _psyche_ of the individual cells
+which compose the tissue, and (2) the _psyche_ of the tissue itself, or
+of the "cell-state" which is made up of the tissues. This "tissue-soul"
+is the higher psychological function which gives physiological
+individuality to the compound multicellular organism as a true
+"cell-commonwealth." It controls all the separate "cell-souls" of the
+social cells--the mutually dependent "citizens" which constitute the
+community. This fundamental twofold character of the _psyche_ in the
+metaphyta and the lower, nerveless metazoa is very important. It may
+be verified by unprejudiced observation and suitable experiment. In
+the first place, each single cell has its own sensation and movement,
+and, in addition, each tissue and each organ, composed of a number
+of homogeneous cells, has its special irritability and psychic unity
+(_e.g._, the pollen and stamens).
+
+A. _The plant-soul_ (_phytopsyche_) is, in our view, the summary of
+the entire psychic activity of the tissue-forming, multicellular plant
+(the _metaphyton_, as distinct from the unicellular _protophyton_);
+it is, however, the subject of the most diverse opinions even at the
+present day. It was once customary to draw an essential distinction
+between the plant and the animal, on the ground that the latter had
+a "soul" and the plant had none. However, an unprejudiced comparison
+of the irritability and movements of various higher plants and lower
+animals convinced many observers, even at the beginning of the century,
+that there must be a "soul" on both sides. At a later date Fechner,
+Leitgeb, and others strongly contended for the plant-soul. But a
+profounder knowledge of the subject was obtained when the similarity
+of the elementary structure of the plant and of the animal was proved
+by the cellular theory, and especially when the similarity of conduct
+of the active, living protoplasm in both was shown in the plasma
+theory of Max Schultze (1859). Modern comparative physiology has
+shown that the physiological attitude towards various stimuli (light,
+heat, electricity, gravity, friction, chemical action, etc.) of the
+"sensitive" portions of many plants and animals is exactly the same,
+and that the reflex movements which the stimuli elicit take place in
+precisely the same manner on both sides. Hence, if it was necessary to
+attribute this activity to a "soul" in the lower, nerveless metazoa
+(sponges, polyps, etc.), it was also necessary in the case of many
+(if not all) metaphyta, at least in the very sensitive _mimosa_, the
+"fly-traps" (_dionaea_ and _drosera_), and the numerous kinds of
+climbing plants.
+
+It is true that modern vegetal physiology has given a purely physical
+explanation of many of these stimulated movements, or tropisms, by
+special features of growth, variations of pressure, etc. Yet these
+mechanical causes are neither more nor less _psychophysical_ than
+the similar "reflex movements" of the sponges, polyps, and other
+nerveless metazoa, even though their mechanism is entirely different.
+The character of the tissue-soul reveals itself in the same way in
+both cases--the cells of the tissue (the regular, orderly structure
+of cells) transmit the stimuli they have received in one part, and
+thus provoke movements of other parts, or of the whole organ. This
+transmission of stimuli has as much title to be called "psychic
+activity" as its more complete form in the higher animals with nerves;
+the anatomic explanation of it is that the social cells of the tissue,
+or cell-community, are not isolated from each other (as was formerly
+supposed), but are connected throughout by fine threads or bridges of
+protoplasm. When the sensitive mimosa closes its graceful leaves and
+droops its stalk at contact, or on being shaken; when the irritable
+fly-trap (the dionæa) swiftly clasps its leaves together at a touch,
+and captures a fly; the sensation seems to be keener, the transmission
+of the stimulus more rapid, and the movement more energetic than in the
+reflex action of the stimulated bath-sponge and many other sponges.
+
+B. _The soul of the nerveless metazoa._--Of very special interest for
+comparative psychology in general, and for the phylogeny of the animal
+soul in particular, is the psychic activity of those lower metazoa
+which have tissues, and sometimes differentiated organs, but no nerves
+or specific organs of sense. To this category belong four different
+groups of the earliest coelenterates: (_a_) the gastræads, (_b_) the
+platodaria, (_c_) the sponges, and (_d_) the hydropolyps, the lowest
+form of cnidaria.
+
+The _gastraeads_ (or animals with a primitive gut) form a small group
+of the lowest coelenterates, which is of great importance as the
+common ancestral group of all the metazoa. The body of these little
+swimming animals looks like a tiny (generally oval) vesicle, which has
+a simple cavity with one opening--the primitive gut and the primitive
+mouth. The wall of the digestive cavity is formed of two simple
+layers of cells, or epithelium, the inner of which--the gut-layer--is
+responsible for the vegetal activity of nourishment, while the outer,
+or skin-layer, discharges the animal functions of movement and
+sensation. The homogeneous sensitive cells of the skin-layer bear long,
+slender hairs or lashes (_cilia_), by the vibration of which the
+swimming motion is effected. The few surviving forms of gastræads,
+the gastræmaria (_trichoplacidae_) and cyemaria (_orthonectidae_),
+are extremely interesting, from the fact that they remain throughout
+life at a stage of structure which is passed by all the other metazoa
+(from the sponge to man) at the commencement of their embryonic
+development. As I have shown in my _Theory of the Gastraea_ (1872),
+a very characteristic embryonic form, the _gastrula_, is immediately
+developed from the _blastula_ in all the tissue animals. The germinal
+membrane (blastoderm), which represents the wall of the hollow vesicle,
+forms a depression at one side, and this soon sinks in so deep that the
+inner cavity of the vesicle disappears. The half of the membrane which
+bends in is thus laid on, and inside, the other half; the latter forms
+the _skin-layer_, or outer germinal layer (ectoderm or epiblast), and
+the former becomes the _gut-layer_, or inner germinal layer (endoderm
+or hypoblast). The new cavity of the cup-shaped body is the digestive
+stomach cavity (the _progaste_), and its opening is the primitive mouth
+(or _prostoma_).[19] The skin-layer, or ectoderm, is the primitive
+psychic organ in the metazoa; from it, in all the nerve animals, not
+only the external skin and the organs of sense, but also the nervous
+system, are developed. In the gastræads, which have no nerves, all the
+cells which compose the simple epithelium of the ectoderm are equally
+organs of sensation and of movement; we have here the tissue-soul in
+its simplest form.
+
+The platodaria, the earliest and simplest form of the platodes, seem to
+be of the same primitive construction. Some of these cryptocoela--the
+_convoluta_, etc.--have no specific nervous system, while their
+nearest relatives, the turbellaria, have already differentiated one,
+and even developed a vertical brain.
+
+The _sponges_ form a peculiar group in the animal world, which differs
+widely in organization from all the other metazoa. The innumerable
+kinds of sponges grow, as a rule, at the bottom of the sea. The
+simplest form of sponge, the _olynthus_, is in reality nothing more
+than a _gastraea_, the body-wall of which is perforated like a sieve,
+with fine pores, in order to permit the entrance of the nourishing
+stream of water. In the majority of sponges--even in the most familiar
+one, the bath-sponge--the bulbous organism constructs a kind of stem or
+tree, which is made up of thousands of these gastræads, and permeated
+by a nutritive system of canals. Sensation and movement are only
+developed in the faintest degree in the sponges; they have no nerves,
+muscles, or organs of sense. It was therefore quite natural that such
+stationary, shapeless, insensitive animals should have been commonly
+taken to be plants in earlier years. Their psychic life--for which no
+special organs have been differentiated--is far inferior to that of the
+mimosa and other sensitive plants.
+
+_The soul of the cnidaria_ is of the utmost importance in comparative
+and phylogenetic psychology; for in this numerous group of the
+coelenterates the historical evolution of the _nerve-soul_ out of the
+_tissue-soul_ is repeated before our eyes. To this group belong the
+innumerable classes of stationary polyps and corals, and of swimming
+medusæ and siphonophora. As the common ancestor of all the cnidaria
+we can safely assign a very simple polyp, which is substantially
+the same in structure as the common, still surviving, fresh-water
+polyp--the hydra. Yet the hydræ, and the stationary, closely related
+_hydropolyps_, have no nerves or higher sense-organs, although they
+are extremely sensitive. On the other hand, the free-swimming medusæ,
+which are developed from them--and are still connected with them
+by alternation of generations--have an independent nervous system
+and specific sense-organs. Here, also, we may directly observe the
+ontogenetic evolution of the nerve-soul (_neuropsyche_) out of the
+tissue-soul (_histopsyche_), and thus learn its phylogenetic origin.
+This is the more interesting as such phenomena are _polyphyletic_--that
+is, they have occurred several times--more than once, at least--quite
+independently. As I have shown elsewhere, the hydromedusæ have arisen
+from the hydropolyps in a different manner from that of the evolution
+of the scyphomedusæ from the scyphopolyps; the gemmation is terminal in
+the case of the latter, and lateral with the former. In addition, both
+groups have characteristic hereditary differences in the more minute
+structure of their psychic organs. The class of siphonophora is also
+very interesting to the psychologist. In these pretty, free-swimming
+organisms, which come from the hydromedusæ we can observe a double
+soul: the _personal soul_ of the numerous individualities which compose
+them, and the common, harmoniously acting psyche of the entire colony.
+
+IV. _The nerve-soul_ (_neuropsyche_): fourth stage of phyletic
+psychogeny.--The psychic life of all the higher animals is conducted,
+as in man, by means of a more or less complicated "psychic apparatus."
+This apparatus is always composed of three chief sections: the _organs
+of sense_ are responsible for the various sensations; the _muscles_
+effect the movements; the _nerves_ form the connection between the
+two by means of a special central organ, the brain or ganglion. The
+arrangement and action of this psychic mechanism have been frequently
+compared with those of a telegraphic system: the nerves are the wires,
+the brain the central, and the sense-organs subordinate stations. The
+motor nerves conduct the commands of the will centrifugally from the
+nerve-centre to the muscles, by the contraction of which they produce
+the movements: the sensitive nerves transmit the various sensations
+centripetally--that is, from the peripheral sense-organs to the
+brain, and thus render an account of the impressions they receive
+from the outer world. The ganglionic cells, or "psychic cells," which
+compose the central nervous organ, are the most perfect of all organic
+elements; they not only conduct the commerce between the muscles and
+the organs of sense, but they also effect the highest performances of
+the animal soul, the formation of ideas and thoughts, and especially
+consciousness.
+
+The great progress of anatomy, physiology, histology, and ontogeny has
+recently added a wealth of interesting discoveries to our knowledge of
+the mechanism of the soul. If speculative philosophy assimilated only
+the most important of these significant results of empirical biology,
+it would have a very different character from that it unfortunately
+presents. As I have not space for an exhaustive treatment of them here,
+I will confine myself to a relation of the chief facts.
+
+Each of the higher animal species has a characteristic psychic organ;
+the central nervous system of each has certain peculiarities of shape,
+position, and composition. The medusæ, among the radiating cnidaria,
+have a ring of nervous matter at the border of the fringe, generally
+provided with four or eight ganglia. The mouth of the five-rayed
+cnidarion is girt with a nerve-ring, from which proceed five branches.
+The bi-symmetrical _platodes_ and the _vermalia_ have a vertical
+brain, or acroganglion, composed of two dorsal ganglia, lying above
+the mouth; from these "upper ganglia" two branch nerves proceed to the
+skin and the muscles. In some of the vermalia and in the mollusca a
+pair of ventral "lower ganglia" are added, which are connected with
+the former by a ring round the gullet. This ring is found also in the
+_articulata_; but in these it is continued on the belly side of the
+long body as a ventral medulla, a double fibre like a rope-ladder,
+which expands into a double ganglion in each member. The vertebrates
+have an entirely different formation of the psychic organ; they have
+always a spinal medulla developed at the back of the body; and from an
+expansion of its fore part there arises subsequently the characteristic
+vesicular brain.[20]
+
+Although the psychic organs of the higher species of animals differ
+very materially in position, form, and composition, nevertheless
+comparative anatomy is in a position to prove a common origin for most
+of them--namely, from the vertical brain of the platodes and vermalia;
+they have all, moreover, had their origin in the outermost layer of the
+embryo, the _ectoderm_, or outer skin-layer. Hence we find the same
+typical structure in all varieties of the central nervous organ--a
+combination of ganglionic cells, or "psychic cells" (the real active
+elementary organs of the soul), and of nerve-fibres, which effect the
+connection and transmission of the action.
+
+The first fact we meet in the comparative psychology of the vertebrates,
+and which should be the empirical starting-point of all scientific
+human psychology, is the characteristic structure of the central
+nervous system. This central psychic organ has a particular position,
+shape, and texture in the vertebrate as it has in all the higher
+species. In every case we find a spinal medulla, a strong cylindrical
+nervous cord, which runs down the middle of the back, in the upper
+part of the vertebral column (or the cord which represents it). In
+every case a number of nerves branch off from this medulla in regular
+division, one pair to each segment or vertebra. In every case this
+medullary cord arises in the same way in the foetus; a fine groove
+appears in the middle axis of the skin at the back; then the parallel
+borders of this medullary groove are lifted up a little, bend over
+towards each other, and form into a kind of tube.
+
+The long dorsal cylindrical medullary tube which is thus formed is
+thoroughly characteristic of the vertebrates; it is always the same in
+the early embryonic sketch of the organism, and it is always the chief
+feature of the different kinds of psychic organ which evolve from it in
+time. Only one single group of invertebrates has a similar structure:
+the rare, marine _tunicata_, copelata, ascidia, and thalidiæ. These
+animals have other important peculiarities of structure (especially
+in the chorda and the gut) which show a striking divergence from
+the other invertebrates and resemblance to the vertebrates. The
+inference we draw is that both these groups, the vertebrates and the
+tunicates, have arisen from a common ancestral group of the vermalia,
+the _prochordonia_.[21] Still, there is a great difference between
+the two classes in the fact that the body of the tunicate does not
+articulate, or form members, and has a very simple organization (most
+of them subsequently attach themselves to the bottom of the sea and
+degenerate). The vertebrate, on the other hand, is characterized
+by an early development of internal members, and the formation of
+pro-vertebræ (_vertebratio_). This prepares the way for the much higher
+development of their organism, which finally attains perfection in man.
+This is easily seen in the finer structure of his spinal cord, and in
+the development of a number of segmental pairs of nerves, the spinal
+nerves, which proceed to the various parts of the body.
+
+The long ancestral history of our "vertebrate soul" commences with the
+formation of the most rudimentary spinal cord in the earliest acrania;
+slowly and gradually, through a period of many millions of years, it
+conducts to that marvellous structure of the human brain which seems
+to entitle the highest primate form to quite an exceptional position
+in nature. Since a clear conception of this slow and steady progress
+of our phyletic psychogeny is indispensable for a true psychology, we
+must divide that vast period into a number of stages or sections: in
+each of them the perfecting of the structure of the nervous centre has
+been accompanied by a corresponding evolution of its function, the
+_psyche_. I distinguish eight of these periods in the phylogeny of
+the spinal cord, which are characterized by eight different groups of
+vertebrates: (1) the acrania; (2) the cyclostomata; (3) the fishes; (4)
+the amphibia; (5) the implacental mammals (monotremes and marsupials);
+(6) the earlier placental mammals, especially the prosimiæ; (7) the
+younger primates, the simiæ; and (8) the anthropoid apes and man.
+
+I. First stage--the _acrania_: their only modern representative is the
+lancelot or amphioxus; the psychic organ remains a simple medullary
+tube, and contains a regularly segmented spinal cord, without brain.
+
+II. Second stage--the _cyclostomata_: the oldest group of the craniota,
+now only represented by the _petromyzontes_ and _myxinoides_:
+the fore-termination of the cord expands into a vesicle, which
+then subdivides into five successive parts--the great-brain,
+intermediate-brain, middle-brain, little-brain, and hind-brain: these
+five cerebral vesicles form the common type from which the brain of all
+craniota has evolved, from the lamprey to man.
+
+III. Third stage--the _primitive fishes_ (_selachii_): similar to the
+modern shark: in these oldest fishes, from which all the gnathostomata
+descend, the more pronounced division of the five cerebral vesicles
+sets in.
+
+IV. Fourth stage--the _amphibia_. These earliest land animals, making
+their first appearance in the Carboniferous period, represent the
+commencement of the characteristic structure of the _tetrapod_ and
+a corresponding development of the fish-brain: it advances still
+further in their Permian successors, the _reptiles_, the earliest
+representatives of which, the _tocosauria_, are the common ancestors of
+all the amniota (reptiles and birds on one side, mammals on the other).
+
+V.-VIII. Fifth to the eighth stages--the _mammals_. I have exhaustively
+treated, and illustrated with a number of plates, in my _Anthropogeny_,
+the evolution of our nervous system and the correlative question of the
+development of the soul. I have now, therefore, merely to refer the
+reader to that work. It only remains for me to add a few remarks on the
+last and most interesting class of facts pertaining to this--to the
+evolution of the soul and its organs within the limits of the class
+mammalia. In doing so, I must remind the reader that the _monophyletic
+origin_ of this class--that is, the descent of all the mammals from
+one common ancestral form (of the Triassic period)--is now fully
+established.
+
+The most important consequence of the monophyletic origin of the
+mammals is the necessity of deriving the human soul from a long
+evolutionary series of other mammal souls. A deep anatomical and
+physiological gulf separated the brain structure and the dependent
+psychic activity of the higher mammals from those of the lower:
+this gulf, however, is completely bridged over by a long series of
+intermediate stages. The period of at least fourteen (more than a
+hundred, on other estimates) million years, which has elapsed since the
+commencement of the Triassic period, is amply sufficient to allow even
+the greatest psychological advance. The following is a summary of the
+results of investigation in this quarter, which has recently been very
+penetrating:
+
+I. The brain of the mammal is differentiated from that of the other
+vertebrates by certain features, which are found in all branches of the
+class; especially by a preponderant development of the first and fourth
+vesicles, the cerebrum and cerebellum, while the third vesicle, the
+middle brain, disappears altogether.
+
+II. The brain development of the lowest and earliest mammals (the
+monotremes, marsupials, and prochoriates) is closely allied to
+that of their palæozoic ancestors, the Carboniferous amphibia (the
+_stegocephala_) and the Permian reptiles (the _tocosauria_).
+
+III. During the Tertiary period commences the typical development of
+the cerebrum, which distinguishes the younger mammals so strikingly
+from the older.
+
+IV. The special development (quantitatively and qualitatively) of
+the cerebrum which is so prominent a feature in man, and which is the
+root of his pre-eminent psychic achievements, is only found, outside
+humanity, in a small section of the most highly developed mammals of
+the earlier Tertiary epoch, especially in the anthropoid apes.
+
+V. The differences of brain structure and psychic faculty which
+separate man from the anthropoid ape are slighter than the corresponding
+interval between the anthropoid apes and the lower primates (the
+earliest simiæ and prosimiæ).
+
+VI. Consequently, the historical, gradual evolution of the human soul
+from a long chain of higher and lower mammal souls must, by application
+of the universally valid phyletic laws of the theory of descent, be
+regarded as a _fact_ which has been scientifically proved.
+
+
+
+
+CHAPTER X
+
+CONSCIOUSNESS
+
+    Consciousness as a Natural Phenomenon--Its Definition--Difficulties
+    of the Problem--Its Relation to the Life of the Soul--Our
+    Human Consciousness--Various Theories: I. Anthropistic
+    Theory (Descartes); II. Neurological Theory (Darwin);
+    III. Animal Theory (Schopenhauer); IV. Biological Theory
+    (Fechner); V. Cellular Theory (Fritz Schultze); VI. Atomistic
+    Theory--Monistic and Dualistic Theories--Transcendental
+    Character of Consciousness--The Ignorabimus Verdict of Du
+    Bois-Reymond--Physiology of Consciousness--Discovery of the
+    Organs of Thought by Flechsig--Pathology--Double and Intermittent
+    Consciousness--Ontogeny of Consciousness: Modifications at
+    Different Ages--Phylogeny of Consciousness--Formation of Concepts
+
+
+No phenomenon of the life of the soul is so wonderful and so variously
+interpreted as consciousness. The most contradictory views are current
+to-day, as they were two thousand years ago, not only with regard to
+the nature of this psychic function and its relation to the body,
+but even as to its diffusion in the organic world and its origin and
+development. It is more responsible than any other psychic faculty for
+the erroneous idea of an "immaterial soul" and the belief in "personal
+immortality"; many of the gravest errors that still dominate even
+our modern civilization may be traced to it. Hence it is that I have
+entitled consciousness "the central mystery of psychology"; it is
+the strong citadel of all mystic and dualistic errors, before whose
+ramparts the best-equipped efforts of reason threaten to miscarry. This
+fact would suffice of itself to induce us to make a special critical
+study of consciousness from our monistic point of view. We shall see
+that consciousness is simply a natural phenomenon like any other
+psychic quality, and that it is subject to the law of substance like
+all other natural phenomena.
+
+Even as to the elementary idea of consciousness, its contents and
+extension, the views of the most distinguished philosophers and
+scientists are widely divergent. Perhaps the meaning of consciousness
+is best conceived as an _internal perception_, and compared with the
+action of _a mirror_. As its two chief departments we distinguish
+objective and subjective consciousness--consciousness of the world,
+the non-ego, and of the ego. By far the greater part of our conscious
+activity, as Schopenhauer justly remarked, belongs to the consciousness
+of the outer world, or the non-ego: this _world-consciousness_
+embraces all possible phenomena of the outer world which are in any
+sense accessible to our minds. Much more contracted is the sphere
+of _self-consciousness_, the internal mirror of all our own psychic
+activity, all our presentations, sensations, and volitions.
+
+Many distinguished thinkers, especially on the physiological side
+(Wundt and Ziehen, for instance) take the ideas of consciousness and
+psychic function to be identical--"all psychic action is conscious";
+the province of psychic life, they say, is coextensive with that
+of consciousness. In our opinion, such a definition gives an undue
+extension to the meaning of consciousness, and occasions many
+errors and misunderstandings. We share, rather, the view of other
+philosophers (Romanes, Fritz Schultze, and Paulsen), that even our
+unconscious presentations, sensations, and volitions pertain to our
+psychic life; indeed, the province of these unconscious psychic actions
+(reflex action, and so forth) is far more extensive than that of
+consciousness. Moreover, the two provinces are intimately connected,
+and are separated by no sharp line of demarcation. An unconscious
+presentation may become conscious at any moment; let our attention be
+withdrawn from it by some other object, and forthwith it disappears
+from consciousness once more.
+
+The only source of our knowledge of consciousness is that faculty
+itself; that is the chief cause of the extraordinary difficulty of
+subjecting it to scientific research. Subject and object are one and
+the same in it: the perceptive subject mirrors itself in its own
+inner nature, which is to be the object of our inquiry. Thus we can
+never have a complete objective certainty of the consciousness of
+others; we can only proceed by a comparison of their psychic condition
+with our own. As long as this comparison is restricted to _normal_
+people we are justified in drawing certain conclusions as to their
+consciousness, the validity of which is unchallenged. But when we pass
+on to consider _abnormal_ individuals (the genius, the eccentric, the
+stupid, or the insane) our conclusions from analogy are either unsafe
+or entirely erroneous. The same must be said with even greater truth
+when we attempt to compare human consciousness with that of the animals
+(even the higher, but especially the lower). In that case such grave
+difficulties arise that the views of physiologists and philosophers
+diverge as widely as the poles on the subject. We shall briefly
+enumerate the most important of these views.
+
+I. _The anthropistic theory of consciousness._--It is peculiar to man.
+To Descartes we must trace the widespread notion that consciousness
+and thought are man's exclusive prerogative, and that he alone is
+blessed with an "immortal soul." This famous French philosopher and
+mathematician (educated in a Jesuit College) established a rigid
+partition between the psychic activity of man and that of the brute.
+In his opinion the human soul, a thinking, immaterial being, is
+completely separated from the body, which is extended and material.
+Yet it is united to the body at a certain point in the brain (the
+_glandula pinealis_) for the purpose of receiving impressions from the
+outer world and effecting muscular movements. The animals, not being
+endowed with thought, have no soul: they are mere automata, or cleverly
+constructed machines, whose sensations, presentations, and volitions
+are purely mechanical, and take place according to the ordinary laws
+of physics. Hence Descartes was a _dualist_ in human psychology, and
+a _monist_ in the psychology of the brute. This open contradiction in
+so clear and acute a thinker is very striking; in explaining it, it
+is not unnatural to suppose that he concealed his real opinion, and
+left the discovery of it to independent scholars. As a pupil of the
+Jesuits, Descartes had been taught to deny the truth in the face of his
+better insight; and perhaps he dreaded the power and the fires of the
+Church. Besides, his sceptical principle, that every sincere effort to
+attain the truth must start with a doubt of the traditional dogma had
+already drawn upon him fanatical accusations of scepticism and atheism.
+The great influence which Descartes had on subsequent philosophy was
+very remarkable, and entirely in harmony with his "book-keeping by
+double entry." The _materialists_ of the seventeenth and eighteenth
+centuries appealed to the Cartesian theory of the animal soul and its
+purely mechanical activity in support of their monistic psychology. The
+_spiritualists_, on the other hand, asserted that their dogma of the
+immortality of the soul and its independence of the body was firmly
+established by Descartes' theory of the human soul. This view is still
+prevalent in the camp of the theologians and dualistic metaphysicians.
+The scientific conception of nature, however, which has been built up
+in the nineteenth century, has, with the aid of empirical progress, in
+physiological and comparative psychology, completely falsified it.
+
+II. _Neurological theory of consciousness._--It is present only
+in man and those higher animals which have a centralized nervous
+system and organs of sense. The conviction that a large number of
+animals--at least the higher mammals--are not less endowed than man
+with a thinking soul and consciousness prevails in modern zoology,
+exact physiology, and the monistic psychology. The immense progress we
+have made in the various branches of biology has contributed to bring
+about a recognition of this important truth. We confine ourselves for
+the present to the higher vertebrates, and especially the mammals.
+That these most intelligent specimens of these highly developed
+vertebrates--apes and dogs, in particular--have a strong resemblance to
+man in their whole psychic life has been recognized and speculated on
+for thousands of years. Their faculty of presentation and sensation,
+of feeling and desire, is so like that of man that we need adduce no
+proof of our thesis. But even the higher associational activity of
+the brain, the formation of judgments and their connection into chains
+of reasoning, thought, and consciousness in the narrower sense, are
+developed in them after the same fashion as in man: they differ only in
+degree, not in kind. Moreover, we learn from comparative anatomy and
+histology that the intricate structure of the brain (both in general
+and in detail) is substantially the same in the mammals as it is in
+man. The same lesson is enforced by comparative ontogeny with regard
+to the origin of these psychic organs. Comparative physiology teaches
+us that the various states of consciousness are just the same in these
+highest placentals as in man; and we learn by experiment that there
+is the same reaction to external stimuli. The higher animals can be
+narcotized by alcohol, chloroform, ether, etc., and may be hypnotized
+by the usual methods, just as in the case of man.
+
+It is, however, impossible to determine mathematically at what stage
+of animal life consciousness is to be first recognized as such. Some
+zoologists draw the line very high in the scale, others very low.
+Darwin, who most accurately distinguishes the various stages of
+consciousness, intelligence, and emotion in the higher animals, and
+explains them by progressive evolution, points out how difficult,
+or even impossible, it is to determine the first beginning of this
+supreme psychic faculty in the lower animals. Personally, out of the
+many contradictory theories, I take that to be most probable which
+holds _the centralization of the nervous system_ to be a condition of
+consciousness; and that is wanting in the lower classes of animals. The
+presence of a central nervous organ, of highly developed sense-organs,
+and an elaborate association of groups of presentations, seem to me to
+be required before the unity of consciousness is possible.
+
+III. _Animal theory of consciousness._--All animals, and they alone,
+have consciousness. This theory would draw a sharp distinction between
+the psychic life of the animal and of the plant. Such a distinction
+was urged by many of the older writers, and was clearly formulated
+by Linné in his celebrated _Systema Naturae_; the two great kingdoms
+of the organic world are, in his opinion, divided by the fact that
+animals have sensation and consciousness, and the plants are devoid
+of them. Later on Schopenhauer laid stress on the same distinction:
+"Consciousness is only known to us as a feature of animal nature.
+Even though it extend upwards through the whole animal kingdom, even
+to man and his reason, the unconsciousness of the plant, from which
+it started, remains as the basic feature. In the lowest animals we
+have but the dawn of it." The inaccuracy of this view was obvious by
+about the middle of the present century, when a deeper study was made
+of the psychic activity of the lower animal forms, especially the
+coelenterates (sponges and cnidaria): they are undoubtedly animals,
+yet there is no more trace of a definite consciousness in them than in
+most of the plants. The distinction between the two kingdoms was still
+further obliterated when more careful research was made into their
+unicellular forms. There is no psychological difference between the
+plasmophagous protozoa and the plasmodomous protophyta, even in respect
+of their consciousness.
+
+IV. _Biological theory of consciousness._--It is found in all
+organisms, animal or vegetal, but not in lifeless bodies (such as
+crystals). This opinion is usually associated with the idea that all
+organisms (as distinguished from inorganic substances) have souls:
+the three ideas--life, soul, and consciousness--are then taken to be
+coextensive. Another modification of this view holds that, though
+these fundamental phenomena of organic life are inseparably connected,
+yet consciousness is only a part of the activity of the soul, and of
+the vital activity. Fechner, in particular, has endeavored to prove
+that the plant has a "soul," in the same sense as an animal is said
+to have one; and many credit the vegetal soul with a consciousness
+similar to that of the animal soul. In truth, the remarkable stimulated
+movements of the leaves of the sensitive plants (the mimosa, drosera,
+and dionæa), the automatic movements of other plants (the clover
+and wood-sorrel, and especially the hedysarum), the movements of
+the "sleeping plants" (particularly the _papilionacea_), etc., are
+strikingly similar to the movements of the lower animal forms: whoever
+ascribes consciousness to the latter cannot refuse it to such vegetal
+forms.
+
+V. _Cellular theory of consciousness._--It is a vital property of every
+cell. The application of the cellular theory to every branch of biology
+involved its extension to psychology. Just as we take the living cell
+to be the "elementary organism" in anatomy and physiology, and derive
+the whole system of the multicellular animal or plant from it, so, with
+equal right, we may consider the "cell-soul" to be the psychological
+unit, and the complex psychic activity of the higher organism to be
+the result of the combination of the psychic activity of the cells
+which compose it. I gave the outlines of this _cellular psychology_
+in my _General Morphology_ in 1866, and entered more fully into the
+subject in my paper on "Cell-Souls and Soul-Cells." I was led to a
+deeper study of this "elementary psychology" by my protracted research
+into the unicellular forms of life. Many of these tiny (generally
+microscopic) protists show similar expressions of sensation and will,
+and similar instincts and movements, to those of higher animals; that
+is especially true of the very sensitive and lively infusoria. In the
+relation of these sensitive cell-organisms to their environment, and in
+many other of their vital expressions (for instance, in the wonderful
+architecture of the rhizopods, the thalamophoræ, and the infusoria),
+we seemed to have clear indications of conscious psychic action. If,
+then, we accept the biological theory of consciousness (No. IV.), and
+credit every psychic function with a share of that faculty, we shall be
+compelled to ascribe it to each independent protist cell. In that case
+its material basis would be either the entire protoplasm of the cell,
+or its nucleus, or a portion of it. In the "psychade theory" of Fritz
+Schultze the elementary consciousness of the _psychade_ would have
+the same relation to the individual cells as personal consciousness
+has to the multicellular organism of the personality in the higher
+animals and man. It is impossible definitively to disprove this theory,
+which I held at one time. Still, I now feel compelled to agree with
+Max Verworn, in his belief that none of the protists have a developed
+self-consciousness, but that their sensations and movements are of an
+unconscious character.
+
+VI. _Atomistic theory of consciousness._--It is an elementary property
+of all atoms. This atomistic hypothesis goes furthest of all the
+different views as to the extension of consciousness. It certainly
+escapes the difficulty which so many philosophers and biologists
+experience in solving the problem of the first origin of consciousness.
+It is a phenomenon of so peculiar a character that a derivation of
+it from other psychic functions seems extremely hazardous. It seemed,
+therefore, the easiest way out of the difficulty to conceive it as an
+inherent property of all matter, like gravitation or chemical affinity.
+On that hypothesis there would be as many forms of this original
+consciousness as there are chemical elements; each atom of hydrogen
+would have its hydrogenic consciousness, each atom of carbon its
+carbonic consciousness, and so forth. There are philosophers, even, who
+ascribe consciousness to the four elements of Empedocles, the union of
+which, by "love and hate," produces the totality of things.
+
+Personally, I have never subscribed to this hypothesis of atomic
+consciousness. I emphasize the point because Emil du Bois-Reymond
+has attributed it to me. In the controversy I had with him (1880) he
+violently attacked my "pernicious and false philosophy," and contended
+that I had, in my paper on "The Perigenesis of the Plastidule," "laid
+it down as a metaphysical axiom that every atom has its individual
+consciousness." On the contrary, I explicitly stated that I conceive
+the elementary psychic qualities of sensation and will, which may
+be attributed to atoms, to be _unconscious_--just as unconscious as
+the elementary memory which I, in company with that distinguished
+physiologist, Ewald Hering, consider to be "a common function of
+all organized matter"--or, more correctly, "living substance." Du
+Bois-Reymond curiously confuses "soul" and "consciousness"; whether
+from oversight or not I cannot say. Since he considers consciousness
+to be a transcendental phenomenon (as we shall see presently), while
+denying that character to other psychic functions--the action of the
+senses, for example--I must infer that he recognizes the difference
+of the two ideas. Other parts of his eloquent speeches contain quite
+the opposite view, for the famous orator not infrequently contradicts
+himself on important questions of principle. However, I repeat that, in
+my opinion, consciousness is only _part_ of the psychic phenomena which
+we find in man and the higher animals; the great majority of them are
+unconscious.
+
+However divergent are the different views as to the nature and
+origin of consciousness, they may, nevertheless, on a clear and
+logical examination, all be reduced to two fundamental theories--the
+transcendental (or dualistic) and the physiological (or monistic).
+I have myself always held the latter view, in the light of my
+evolutionary principles, and it is now shared by a great number of
+distinguished scientists, though it is by no means generally accepted.
+The transcendental theory is the older and much more common; it
+has recently come once more into prominence, principally through
+Du Bois-Reymond, and it has acquired a great importance in modern
+discussions of cosmic problems through his famous "Ignorabimus speech."
+On account of the extreme importance of this fundamental question we
+must touch briefly on its main features.
+
+In the celebrated discourse on "The Limits of Natural Science,"
+which E. du Bois-Reymond gave on August 14, 1872, at the Scientific
+Congress at Leipzig, he spoke of two "absolute limits" to our possible
+knowledge of nature which the human mind will never transcend in its
+most advanced science--_never_, as the oft-quoted termination of the
+address, "Ignorabimus," emphatically pronounces. The first absolutely
+insoluble "world-enigma" is the "connection of matter and force," and
+the distinctive character of these fundamental natural phenomena; we
+shall go more fully into this "problem of substance" in the twelfth
+chapter. The second insuperable difficulty of philosophy is given as
+the problem of consciousness--the question how our mental activity
+is to be explained by material conditions, especially movements, how
+"substance [the substance which underlies matter and force] comes,
+under certain conditions, to feel, to desire, and to think."
+
+For brevity, and in order to give a characteristic name to the Leipzig
+discourse, I have called it the "Ignorabimus speech"; this is the
+more permissible, as E. du Bois-Reymond himself, with a just pride,
+eight years afterwards, speaking of the extraordinary consequences
+of his discourse, said: "Criticism sounded every possible note, from
+friendly praise to the severest censure, and the word 'Ignorabimus,'
+which was the culmination of my inquiry, was at once transformed into a
+kind of scientific shibboleth." It is quite true that loud praise and
+approbation resounded in the halls of the dualistic and spiritualistic
+philosophy, and especially in the camp of the "Church militant"; even
+the spiritists and the host of believers, who thought the immortality
+of their precious souls was saved by the "Ignorabimus," joined in the
+chorus. The "severest censure" came at first only from a few scientists
+and philosophers--from the few who had sufficient scientific knowledge
+and moral courage to oppose the dogmatism of the all-powerful secretary
+and dictator of the Berlin Academy of Science.
+
+Towards the end, however, the author of the "Ignorabimus speech" briefly
+alluded to the question whether these two great "world-enigmas," the
+general problem of substance and the special problem of consciousness,
+are not two aspects of one and the same problem. "This idea," he said,
+"is certainly the simplest, and preferable to the one which makes the
+world doubly incomprehensible. Such, however, is the nature of things
+that even here we can obtain no clear knowledge, and it is useless to
+speak further of the question." The latter sentiment I have always
+stoutly contested, and have endeavored to prove that the two great
+questions are not two distinct problems. "The neurological problem
+of consciousness is but a particular aspect of the all-pervading
+cosmological problem of substance."
+
+The peculiar phenomenon of consciousness is not, as Du Bois-Reymond
+and the dualistic school would have us believe, a completely
+"transcendental" problem; it is, as I showed thirty-three years ago,
+a _physiological_ problem, and, as such, must be reduced to the
+phenomena of physics and chemistry. I subsequently gave it the more
+definite title of a _neurological_ problem, as I share the view that
+true consciousness (thought and reason) is only present in those higher
+animals which have a centralized nervous system and organs of sense
+of a certain degree of development. Those conditions are certainly
+found in the higher vertebrates, especially in the placental mammals,
+the class from which man has sprung. The consciousness of the highest
+apes, dogs, elephants, etc., differs from that of man in degree only,
+not in kind, and the graduated interval between the consciousness of
+these "rational" placentals and that of the lowest races of men (the
+Veddahs, etc.) is less than the corresponding interval between these
+uncivilized races and the highest specimens of thoughtful humanity
+(Spinoza, Goethe, Lamarck, Darwin, etc.). Consciousness is but a part
+of the higher activity of the soul, and as such it is dependent on the
+normal structure of the corresponding psychic organ, the brain.
+
+Physiological observation and experiment determined twenty years ago
+that the particular portion of the mammal-brain which we call the
+_seat_ (preferably the _organ_) of consciousness is a part of the
+cerebrum, an area in the late-developed gray bed, or cortex, which
+is evolved out of the convex dorsal portion of the primary cerebral
+vesicle, the "fore-brain." Now, the morphological proof of this
+physiological thesis has been successfully given by the remarkable
+progress of the microscopic anatomy of the brain, which we owe to the
+perfect methods of research of modern science (Kölliker, Flechsig,
+Golgi, Edinger, Weigert, and others).
+
+The most important development is the discovery of the _organs of
+thought_ by Paul Flechsig, of Leipzig; he proved that in the gray bed
+of the brain are found the four seats of the central sense-organs,
+or four "inner spheres of sensation"--the sphere of touch in the
+vertical lobe, the sphere of smell in the frontal lobe, the sphere
+of sight in the occipital lobe, and the sphere of hearing in the
+temporal lobe. Between these four "sense-centres" lie the four great
+"thought-centres," or centres of association, the _real organs of
+mental life_; they are those highest instruments of psychic activity
+that produce thought and consciousness. In front we have the frontal
+brain or centre of association; behind, on top there is the vertical
+brain, or parietal centre of association, and underneath the principal
+brain, or "the great occipito-temporal centre of association" (the
+most important of all); lower down, and internally, the insular brain
+or the insula of Reil, the insular centre of association. These four
+"thought-centres," distinguished from the intermediate "sense-centres"
+by a peculiar and elaborate nerve-structure, are the true and sole
+organs of thought and consciousness. Flechsig has recently pointed out
+that, in the case of man, very specific structures are found in one
+part of them; these structures are wanting in the other mammals, and
+they, therefore, afford an explanation of the superiority of man's
+mental powers.
+
+The momentous announcement of modern physiology, that the cerebrum is
+the organ of consciousness and mental action in man and the higher
+mammals, is illustrated and confirmed by the pathological study of
+its diseases. When parts of the cortex are destroyed by disease their
+respective functions are affected, and thus we are enabled, to some
+extent, to localize the activities of the brain; when certain parts
+of the area are diseased, that portion of thought and consciousness
+disappears which depends on those particular sections. Pathological
+experiment yields the same result; the decay of some known area (for
+instance, the centre of speech) extinguishes its function (speech).
+In fact, there is proof enough in the most familiar phenomena of
+consciousness of their complete dependence on chemical changes in
+the substance of the brain. Many beverages (such as coffee and
+tea) stimulate our powers of thought; others (such as wine and
+beer) intensify feeling; musk and camphor reanimate the fainting
+consciousness; ether and chloroform deaden it, and so forth. How
+would that be possible if consciousness were an immaterial entity,
+independent of these anatomical organs? And what becomes of the
+consciousness of the "immortal soul" when it no longer has the use of
+these organs?
+
+These and other familiar facts prove that man's consciousness--and
+that of the nearest mammals--is _changeable_, and that its activity
+is always open to modification from inner (alimentation, circulation,
+etc.) and outer causes (lesion of the brain, stimulation, etc.).
+Very instructive, too, are the facts of double and intermittent
+consciousness, which remind us of "alternate generations of
+presentations." The same individual has an entirely different
+consciousness on different days, with a change of circumstances; he
+does not know to-day what he did yesterday: yesterday he could say, "I
+am I"; to-day he must say, "I am another being." Such intermittence of
+consciousness may last not only days, but months, and even years; the
+change may even become permanent.
+
+As everybody knows, the new-born infant has no consciousness. Preyer
+has shown that it is only developed after the child has begun to
+speak; for a long time it speaks of itself in the third person.
+In the important moment when it first pronounces the word "I,"
+when the feeling of self becomes clear, we have the beginning of
+self-consciousness, and of the antithesis to the non-ego. The rapid
+and solid progress in knowledge which the child makes in its first
+ten years, under the care of parents and teachers, and the slower
+progress of the second decade, until it reaches complete maturity of
+mind, are intimately connected with a great advancement in the growth
+and development of consciousness and of its organ, the brain. But even
+when the pupil has got his "certificate of maturity" his consciousness
+is still far from mature; it is then that his "world-consciousness"
+first begins to develop, in his manifold relations with the outer
+world. Then, in the third decade, we have the full maturity of rational
+thought and consciousness, which, in cases of normal development, yield
+their ripe fruits during the next three decades. The slow, gradual
+degeneration of the higher mental powers, which characterizes senility,
+usually sets in at the commencement of the seventh decade--sometimes
+earlier, sometimes later. Memory, receptiveness, and interest in
+particular objects gradually decay; though productivity, mature
+consciousness, and philosophic interest in general truths often remain
+for many years longer.
+
+The individual development of consciousness in earlier youth proves the
+universal validity of the _biogenetic law_; and, indeed, it is still
+recognizable in many ways during the later years. In any case, the
+ontogenesis of consciousness makes it perfectly clear that it is not
+an "immaterial entity," but a physiological function of the brain, and
+that it is, consequently, no exception to the general law of substance.
+
+From the fact that consciousness, like all other psychic functions,
+is dependent on the normal development of certain organs, and that
+it gradually unfolds in the child in proportion to the development
+of those organs, we may already conclude that it has arisen in the
+animal kingdom by a gradual historical development. Still, however
+certain we are of the fact of this natural evolution of consciousness,
+we are, unfortunately, not yet in a position to enter more deeply
+into the question and construct special hypotheses in elucidation
+of it. Palæontology, it is true, gives us a few facts which are not
+without significance. For instance, the quantitative and qualitative
+development of the brain of the placental mammals during the Tertiary
+period is very remarkable. The cavity of many of the fossil skulls of
+the period has been carefully examined, and has given us a good deal of
+reliable information as to the size, and, to some extent, as to the
+structure, of the brain they enclosed. We find, within the limits of
+one and the same group (the ungulates, the rodents, or the primates), a
+marked advance in the later miocene and pliocene specimens as compared
+with the earlier eocene and oligocene representatives of the same stem;
+in the former the brain (in proportion to the size of the organism) is
+six to eight times as large as in the latter.
+
+Moreover, that highest stage of consciousness, which is reached by man
+alone, has been evolved step by step--even by the very progress of
+civilization--from a lower condition, as we find illustrated to-day in
+the case of uncivilized races. That is easily proved by a comparison
+of their languages, which is closely connected with the comparison of
+their ideas. The higher the conceptual faculty advances in thoughtful
+civilized man, the more qualified he is to detect common features amid
+a multitude of details, and embody them in general concepts, and so
+much the clearer and deeper does his consciousness become.
+
+
+
+
+CHAPTER XI
+
+THE IMMORTALITY OF THE SOUL
+
+    The Citadel of Superstition--Athanatism and Thanatism--Individual
+    Character of Death--Immortality of the Unicellular Organisms
+    (Protists)--Cosmic and Personal Immortality--Primary Thanatism (of
+    Uncivilized Peoples)--Secondary Thanatism (of Ancient and Recent
+    Philosophers)--Athanatism and Religion--Origin of the Belief
+    in Immortality--Christian Athanatism--Eternal Life--The Day of
+    Judgment--Metaphysical Athanatism--Substance of the Soul--Ether
+    Souls and Air Souls; Fluid Souls and Solid Souls--Immortality of
+    the Animal Soul--Arguments for and Against Athanatism--Athanatist
+    Illusions
+
+
+When we turn from the genetic study of the soul to the great question
+of its immortality, we come to that highest point of superstition which
+is regarded as the impregnable citadel of all mystical and dualistic
+notions. For in this crucial question, more than in any other problem,
+philosophic thought is complicated by the selfish interest of the human
+personality, who is determined to have a guarantee of his existence
+beyond the grave at any price. This "higher necessity of feeling" is
+so powerful that it sweeps aside all the logical arguments of critical
+reason. Consciously or unconsciously, most men are influenced in all
+their general views, and, therefore, in their theory of life, by the
+dogma of personal immortality; and to this theoretical error must be
+added practical consequences of the most far-reaching character. It is
+our task, therefore, to submit every aspect of this important dogma to
+a critical examination, and to prove its untenability in the light of
+the empirical data of modern biology.
+
+In order to have a short and convenient expression for the two opposed
+opinions on the question, we shall call the belief in man's personal
+immortality "athanatism" (from _athanes_ or _athanatos_ == immortal).
+On the other hand, we give the name of "thanatism" (from _thanatos_
+== death) to the opinion which holds that at a man's death not only
+all the other physiological functions are arrested, but his "soul"
+also disappears--that is, that sum of cerebral functions which psychic
+dualism regards as a peculiar entity, independent of the other vital
+processes in the living body.
+
+In approaching this physiological problem of death we must point out
+the _individual_ character of this organic phenomenon. By death we
+understand simply the definitive cessation of the vital activity of
+the _individual_ organism, no matter to which category or stage of
+individuality the organism in question belongs. Man is dead when his
+own personality ceases to exist, whether he has left offspring that
+they may continue to propagate for many generations or not. In a
+certain sense we often say that the minds of great men (in a dynasty
+of eminent rulers, for instance, or a family of talented artists) live
+for many generations; and in the same way we speak of the "soul" of
+a noble woman living in her children and children's children. But in
+these cases we are dealing with intricate phenomena of _heredity_,
+in which a microscopic cell (the sperm-cell of the father or the
+egg-cell of the mother) transmits certain features to offspring. The
+particular personalities who produce those sexual cells in thousands
+are mortal beings, and at their death their personal psychic activity
+is extinguished like every other physiological function.
+
+A number of eminent zoologists--Weismann being particularly
+prominent--have recently defended the opinion that only the lowest
+unicellular organisms, the protists, are immortal, in contradistinction
+to the multicellular plants and animals, whose bodies are formed of
+tissues. This curious theory is especially based on the fact that
+most of the protists multiply without sexual means, by division or
+the formation of spores. In such processes the whole body of the
+unicellular organism breaks up into two or more equal parts (daughter
+cells), and each of these portions completes itself by further growth
+until it has the size and form of the mother cell. However, by the very
+process of division the _individuality_ of the unicellular creature
+has been destroyed; both its physiological and its morphological unity
+have gone. The view of Weismann is logically inconsistent with the
+very notion of _individual_--an "indivisible" entity; for it implies
+a unity which cannot be divided without destroying its nature. In
+this sense the unicellular protophyta and protozoa are throughout
+life _physiological individuals_, just as much as the multicellular
+tissue-plants and animals. A sexual propagation by simple division
+is found in many of the multicellular species (for instance, in many
+cnidaria, corals, medusæ, etc.); the mother animal, the division of
+which gives birth to the two daughter animals, ceases to exist with
+the segmentation. "The protozoa," says Weismann, "have no individuals
+and no generations in the metazoic sense." I must entirely dissent
+from his thesis. As I was the first to introduce the title of
+_metazoa_, and oppose these multicellular, tissue-forming animals to
+the unicellular _protozoa_ (infusoria, rhizopods, etc.), and as I was
+the first to point out the essential difference in the development of
+the two (the former from germinal layers, and the latter not), I must
+protest that I consider the _protozoa_ to be just as mortal in the
+physiological (and psychological) sense as the _metazoa_; neither body
+nor soul is immortal in either group. The other erroneous consequences
+of Weismann's notion have been refuted by Moebius (1884), who justly
+remarks that "every event in the world is periodic," and that "there is
+no source from which immortal organic individuals might have sprung."
+
+When we take the idea of immortality in the widest sense, and extend
+it to the totality of the knowable universe, it has a scientific
+significance; it is then not merely acceptable, but self-evident,
+to the monistic philosopher. In that sense the thesis of the
+indestructibility and eternal duration of all that exists is equivalent
+to our supreme law of nature, the _law of substance_ (see chap. xii).
+As we intend to discuss this immortality of the cosmos fully later on,
+in establishing the theory of the persistence of matter and force,
+we shall not dilate on it at present. We pass on immediately to the
+criticism of that belief in immortality which is the only sense usually
+attached to the word, the immortality of the individual soul. We
+shall first inquire into the extent and the origin of this mystic and
+dualistic notion, and point out, in particular, the wide acceptance
+of the contradictory thesis, our monistic, empirically established
+_thanatism_. I must distinguish two essentially different forms of
+thanatism--primary and secondary; primary thanatism is the original
+absence of the dogma of immortality (in the primitive uncivilized
+races); secondary thanatism is the later outcome of a rational
+knowledge of nature in the civilized intelligence.
+
+We still find it asserted in philosophic, and especially in theological,
+works that belief in the personal immortality of the human soul was
+originally shared by all men--or, at least, by all "rational" men. That
+is not the case. This dogma is not an original idea of the human mind,
+nor has it ever found universal acceptance. It has been absolutely
+proved by modern comparative ethnology that many uncivilized races
+of the earliest and most primitive stage had no notion either of
+immortality or of God. That is true, for instance, of the Veddahs of
+Ceylon, those primitive pygmies whom, on the authority of the able
+studies of the Sarasins, we consider to be a relic of the earliest
+inhabitants of India;[22] it is also the case in several of the
+earliest groups of the nearly related Dravidas, the Indian Seelongs,
+and some native Australian races. Similarly, several of the primitive
+branches of the American race, in the interior of Brazil, on the upper
+Amazon, etc., have no knowledge either of gods or immortality. This
+_primary_ absence of belief in immortality and deity is an extremely
+important fact; it is, obviously, easy to distinguish from the
+_secondary_ absence of such belief, which has come about in the highest
+civilized races as the result of laborious critico-philosophical study.
+
+Differently from the primary thanatism which originally characterized
+primitive man, and has always been widely spread, the _secondary_
+absence of belief in immortality is only found at a late stage of
+history: it is the ripe fruit of profound reflection on life and death,
+the outcome of bold and independent philosophical speculation. We first
+meet it in some of the Ionic philosophers of the sixth century B.C.,
+then in the founders of the old materialistic philosophy, Democritus
+and Empedocles, and also in Simonides and Epicurus, Seneca and Plinius,
+and in an elaborate form in Lucretius Carus. With the spread of
+Christianity at the decay of classical antiquity, athanatism, one of
+its chief articles of faith, dominated the world, and so, amid other
+forms of superstition, the myth of personal immortality came to be
+invested with a high importance.
+
+Naturally, through the long night of the Dark Ages it was rarely that
+a brave free-thinker ventured to express an opinion to the contrary:
+the examples of Galileo, Giordano Bruno, and other independent
+philosophers, effectually destroyed all freedom of utterance. Heresy
+only became possible when the Reformation and the Renaissance had
+broken the power of the papacy. The history of modern philosophy tells
+of the manifold methods by which the matured mind of man sought to
+rid itself of the superstition of immortality. Still, the intimate
+connection of the belief with the Christian dogma invested it with
+such power, even in the more emancipated sphere of Protestantism,
+that the majority of convinced free-thinkers kept their sentiments to
+themselves. From time to time some distinguished scholar ventured to
+make a frank declaration of his belief in the impossibility of the
+continued life of the soul after death. This was done in France in the
+second half of the eighteenth century by Voltaire, Danton, Mirabeau,
+and others, and by the leaders of the materialistic school of those
+days, Holbach, Lamettrie, etc. The same opinion was defended by the
+able friend of the Materialists, the greatest of the Hohenzollerns, the
+monistic "philosopher of Sans-souci." What would Frederick the Great,
+the "crowned thanatist and atheist," say, could he compare his monistic
+views with those of his successor of to-day?
+
+Among thoughtful physicians the conviction that the existence of the
+soul came to an end at death has been common for centuries: generally,
+however, they refrained from giving it expression. Moreover, the
+empirical science of the brain remained so imperfect during the last
+century that the soul could continue to be regarded as its mysterious
+inhabitant. It was the gigantic progress of biology in the present
+century, and especially in the latter half of the century, that
+finally destroyed the myth. The establishment of the theory of descent
+and the cellular theory, the astounding discoveries of ontogeny and
+experimental physiology--above all, the marvellous progress of the
+microscopic anatomy of the brain, gradually deprived athanatism of
+every basis; now, indeed, it is rarely that an informed and honorable
+biologist is found to defend the immortality of the soul. All the
+monistic philosophers of the century (Strauss, Feuerbach, Büchner,
+Spencer, etc.) are thanatists.
+
+The dogma of personal immortality owes its great popularity and its
+high importance to its intimate connection with the teaching of
+Christianity. This circumstance gave rise to the erroneous and still
+prevalent belief that the myth is a fundamental element of all the
+higher religions. That is by no means the case. The higher Oriental
+religions include no belief whatever in the immortality of the soul;
+it is not found in Buddhism, the religion that dominates thirty per
+cent. of the entire human race; it is not found in the ancient popular
+religion of the Chinese, nor in the reformed religion of Confucius
+which succeeded it; and, what is still more significant, it is not
+found in the earlier and purer religion of the Jews. Neither in the
+"five Mosaic books," nor in any of the writings of the Old Testament
+which were written before the Babylonian Exile, is there any trace of
+the notion of individual persistence after death.
+
+The mystic notion that the human soul will live forever after death has
+had a polyphyletic origin. It was unknown to the earliest speaking man
+(the hypothetical _homo primigenius_ of Asia), to his predecessors, of
+course, the _pithecanthropus_ and _prothylobates_, and to the least
+developed of his modern successors, the Veddahs of Ceylon, the Seelongs
+of India, and other distant races. With the development of reason and
+deeper reflection on life and death, sleep and dreams, mystic ideas of
+a dualistic composition of our nature were evolved--independently of
+each other--in a number of the earlier races. Very different influences
+were at work in these polyphyletic creations--worship of ancestors,
+love of relatives, love of life and desire of its prolongation, hope of
+better conditions of life beyond the grave, hope of the reward of good
+and punishment of evil deeds, and so forth. Comparative psychology has
+recently brought to our knowledge a great variety of myths and legends
+of that character; they are, for the most part, closely associated
+with the oldest forms of theistic and religious belief. In most of the
+modern religions athanatism is intimately connected with theism; the
+majority of believers transfer their materialistic idea of a "personal
+God" to their "immortal soul." That is particularly true of the
+dominant religion of modern civilized states, Christianity.
+
+As everybody knows, the dogma of the immortality of the soul has long
+since assumed in the Christian religion that rigid form which it
+has in the articles of faith: "I believe in the resurrection of the
+body and in an eternal life." Man will arise on "the last day," as
+Christ is alleged to have done on Easter morn, and receive a reward
+according to the tenor of his earthly life. This typically Christian
+idea is thoroughly materialistic and anthropomorphic; it is very little
+superior to the corresponding crude legends of uncivilized peoples. The
+impossibility of "the resurrection of the body" is clear to every man
+who has some knowledge of anatomy and physiology. The resurrection of
+Christ, which is celebrated every Easter by millions of Christians, is
+as purely mythical as "the awakening of the dead," which he is alleged
+to have taught. These mystic articles of faith are just as untenable in
+the light of pure reason as the cognate hypothesis of "eternal life."
+
+The fantastic notions which the Christian Church disseminates as to the
+eternal life of the immortal soul after the dissolution of the body are
+just as materialistic as the dogma of "the resurrection of the body."
+In his interesting work on _Religion in the Light of the Darwinian
+Theory_, Savage justly remarks: "It is one of the standing charges of
+the Church against science that it is materialistic. I must say, in
+passing, that the whole ecclesiastical doctrine of a future life has
+always been, and still is, materialism of the purest type. It teaches
+that the material body shall rise, and dwell in a material heaven." To
+prove this one has only to read impartially some of the sermons and
+ornate discourses in which the glory of the future life is extolled
+as the highest good of the Christian, and belief in it is laid down to
+be the foundation of morality. According to them, all the joys of the
+most advanced modern civilization await the pious believer in Paradise,
+while the "All-loving Father" reserves his eternal fires for the
+godless materialist.
+
+In opposition to the materialist athanatism, which is dominant in
+the Christian and Mohammedan Churches, we have, apparently, a purer
+and higher form of faith in the _metaphysical athanatism_, as taught
+by most of our dualist and spiritualist philosophers. Plato must be
+considered its chief creator: in the fourth century before Christ
+he taught that complete dualism of body and soul which afterwards
+became one of the most important, theoretically, and one of the most
+influential, practically, of the Christian articles of faith. The
+body is mortal, material, physical; the soul is immortal, immaterial,
+metaphysical. They are only temporarily associated, for the course of
+the individual life. As Plato postulated an eternal life before as well
+as after this temporary association, he must be classed as an adherent
+of "metempsychosis," or transmigration of souls; the soul existed as
+such, or as an "eternal idea," before it entered into a human body.
+When it quits one body it seeks such other as is most suited to its
+character for its habitation. The souls of bloody tyrants pass into the
+bodies of wolves and vultures, those of virtuous toilers migrate into
+the bodies of bees and ants, and so forth. The childish naïvety of this
+Platonic morality is obvious; on closer examination his views are found
+to be absolutely incompatible with the scientific truth which we owe to
+modern anatomy, physiology, histology, and ontogeny; we mention them
+only because, in spite of their absurdity, they have had a profound
+influence on thought and culture. On the one hand, the mysticism of the
+Neo-Platonists, which penetrated into Christianity, attaches itself to
+the psychology of Plato; on the other hand, it became subsequently one
+of the chief supports of spiritualistic and idealistic philosophy. The
+Platonic "idea" gave way in time to the notion of psychic "substance";
+this is just as incomprehensible and metaphysical, though it often
+assumed a physical appearance.
+
+The conception of the soul as a "substance" is far from clear in many
+psychologists; sometimes it is regarded as an "immaterial" entity of
+a peculiar character in an abstract and idealistic sense, sometimes
+in a concrete and realistic sense, and sometimes as a confused
+_tertium quid_ between the two. If we adhere to the monistic idea of
+substance, which we develop in chap. xii., and which takes it to be
+the simplest element of our whole world-system, we find _energy_ and
+_matter_ inseparably associated in it. We must, therefore, distinguish
+in the "substance of the soul" the characteristic psychic _energy_
+which is all we perceive (sensation, presentation, volition, etc.),
+and the psychic _matter_, which is the inseparable basis of its
+activity--that is, the living protoplasm. Thus, in the higher animals
+the "matter" of the soul is a part of the nervous system; in the lower
+nerveless animals and plants it is a part of their multicellular
+protoplasmic body; and in the unicellular protists it is a part of
+their protoplasmic cell-body. In this way we are brought once more
+to the psychic organs, and to an appreciation of the fact that these
+material organs are indispensable for the action of the soul; but the
+soul itself is _actual_--it is the sum-total of their physiological
+functions.
+
+However, the idea of a specific "soul-substance" found in the
+dualistic philosophers who admit such a thing is very different from
+this. They conceive the immortal soul to be material, yet invisible,
+and essentially different from the visible body which it inhabits.
+
+Thus _invisibility_ comes to be regarded as a most important attribute
+of the soul. Some, in fact, compare the soul with ether, and regard
+it, like ether, as an extremely subtle, light, and highly elastic
+material, an imponderable agency, that fills the intervals between the
+ponderable particles of the living organism, others compare the soul
+with the wind, and so give it a gaseous nature; and it is this simile
+which first found favor with primitive peoples, and led in time to the
+familiar dualistic conception. When a man died, the body remained as a
+lifeless corpse, but the immortal soul "flew out of it with the last
+breath."
+
+The comparison of the human soul with physical ether as a qualitatively
+similar idea has assumed a more concrete shape in recent times through
+the great progress of optics and electricity (especially in the last
+decade); for these sciences have taught us a good deal about the
+energy of ether, and enabled us to formulate certain conclusions as
+to the material character of this all-pervading agency. As I intend
+to describe these important discoveries later on (in chap. xii.), I
+shall do no more at present than briefly point out that they render
+the notion of an "etheric soul" absolutely untenable. Such an etheric
+soul--that is a psychic substance--which is similar to physical ether,
+and which, like ether, passes between the ponderable elements of the
+living protoplasm or the molecules of the brain, cannot possibly
+account for the individual life of the soul. Neither the mystic
+notions of that kind which were warmly discussed about the middle
+of the century, nor the attempts of modern "Neovitalists" to put
+their mystical "vital force" on a line with physical ether, call for
+refutation any longer.
+
+Much more widespread, and still much respected, is the view which
+ascribes a gaseous nature to the substance of the soul. The comparison
+of human breath with the wind is a very old one; they were originally
+considered to be identical, and were both given the same name. The
+_anemos_ and _psyche_ of the Greeks, and the _anima_ and _spiritus_
+of the Romans, were originally all names for "a breath of wind"; they
+were transferred from this to the breath of man. After a time this
+"living breath" was identified with the "vital force," and finally it
+came to be regarded as the soul itself, or, in a narrower sense, as its
+highest manifestation, the "spirit." From that the imagination went on
+to derive the mystic notion of individual "spirits"; these, also, are
+still usually conceived as "aëriform beings"--though they are credited
+with the physiological functions of an organism, and they have been
+photographed in certain well-known spiritist circles.
+
+Experimental physics has succeeded, during the last decade of the
+century, in reducing all gaseous bodies to a liquid--most of them,
+also, to a solid--condition. Nothing more is needed than special
+apparatus, which exerts a violent pressure on the gases at a very low
+temperature. By this process not only the atmospheric elements, oxygen,
+hydrogen, and nitrogen, but even compound gases (such as carbonic-acid
+gas) and gaseous aggregates (like the atmosphere) have been changed
+from gaseous to liquid form. In this way the "invisible" substances
+have become "visible" to all, and in a certain sense "tangible."
+With this transformation the mystic nimbus which formerly veiled
+the character of the gas in popular estimation--as an invisible body
+that wrought visible effects--has entirely disappeared. If, then, the
+substance of the soul were really gaseous, it should be possible to
+liquefy it by the application of a high pressure at a low temperature.
+We could then catch the soul as it is "breathed out" at the moment of
+death, condense it, and exhibit it in a bottle as "immortal fluid"
+(_Fluidum animae immortale_). By a further lowering of temperature and
+increase of pressure it might be possible to solidify it--to produce
+"soul-snow." The experiment has not yet succeeded.
+
+If athanatism were true, if, indeed, the human soul were to live for
+all eternity, we should have to grant the same privilege to the souls
+of the higher animals, at least to those of the nearest related mammals
+(apes, dogs, etc.). For man is not distinguished from them by a special
+_kind_ of soul, or by any peculiar and exclusive psychic function,
+but only by a higher _degree_ of psychic activity, a superior stage
+of development. In particular, consciousness--the function of the
+association of ideas, thought, and reason--has reached a higher level
+in many men (by no means in all) than in most of the animals. Yet this
+difference is far from being so great as is popularly supposed; and it
+is much slighter in every respect than the corresponding difference
+between the higher and the lower animal souls, or even the difference
+between the highest and the lowest stages of the human soul itself. If
+we ascribe "personal immortality" to man, we are bound to grant it also
+to the higher animals.
+
+It is, therefore, quite natural that we should find this belief in
+the immortality of the animal soul among many ancient and modern
+peoples; we even meet it sometimes to-day in many thoughtful men
+who postulate an "immortal life" for themselves, and have, at the
+same time, a thorough empirical knowledge of the psychic life of the
+animals. I once knew an old head-forester, who, being left a widower
+and without children at an early age, had lived alone for more than
+thirty years in a noble forest of East Prussia. His only companions
+were one or two servants, with whom he exchanged merely a few necessary
+words, and a great pack of different kinds of dogs, with which he
+lived in perfect psychic communion. Through many years of training
+this keen observer and friend of nature had penetrated deep into the
+individual souls of his dogs, and he was as convinced of their personal
+immortality as he was of his own. Some of his most intelligent dogs
+were, in his impartial and objective estimation, at a higher stage of
+psychic development than his old, stupid maid and the rough, wrinkled
+manservant. Any unprejudiced observer, who will study the conscious
+and intelligent psychic activity of a fine dog for a year, and follow
+attentively the physiological processes of its thought, judgment,
+and reason, will have to admit that it has just as valid a claim to
+immortality as man himself.
+
+The proofs of the immortality of the soul, which have been adduced for
+the last two thousand years, and are, indeed, still credited with some
+validity, have their origin, for the most part, not in an effort to
+discover the truth, but in an alleged "necessity of emotion"--that is,
+in imagination and poetic conceit. As Kant puts it, the immortality of
+the soul is not an object of pure reason, but a "postulate of practical
+reason." But we must set "practical reason" entirely aside, together
+with all the "exigencies of emotion, or of moral education, etc.," when
+we enter upon an honest and impartial pursuit of truth; for we shall
+only attain it by the work of pure reason, starting from empirical
+data and capable of logical analysis. We have to say the same of
+athanatism as of theism; both are creations of poetic mysticism and of
+transcendental "faith," not of rational science.
+
+When we come to analyze all the different proofs that have been urged
+for the immortality of the soul, we find that not a single one of them
+is of a scientific character; not a single one is consistent with the
+truths we have learned in the last few decades from physiological
+psychology and the theory of descent. The _theological_ proof--that
+a personal creator has breathed an immortal soul (generally regarded
+as a portion of the divine soul) into man--is a pure myth. The
+_cosmological_ proof--that the "moral order of the world" demands
+the eternal duration of the human soul--is a baseless dogma. The
+_teleological_ proof--that the "higher destiny" of man involves the
+perfecting of his defective, earthly soul beyond the grave--rests
+on a false anthropism. The _moral_ proof--that the defects and
+the unsatisfied desires of earthly existence must be fulfilled by
+"compensative justice" on the other side of eternity--is nothing
+more than a pious wish. The _ethnological_ proof--that the belief in
+immortality, like the belief in God, is an innate truth, common to
+all humanity--is an error in fact. The _ontological_ proof--that the
+soul, being a "simple, immaterial, and indivisible entity," cannot be
+involved in the corruption of death--is based on an entirely erroneous
+view of the psychic phenomena; it is a spiritualistic fallacy. All
+these and similar "proofs of athanatism" are in a parlous condition;
+they are definitely annulled by the scientific criticism of the last
+few decades.
+
+The extreme importance of the subject leads us to oppose to these
+untenable "proofs of immortality" a brief exposition of the sound
+scientific arguments against it. The _physiological_ argument shows
+that the human soul is not an independent, immaterial substance, but,
+like the soul of all the higher animals, merely a collective title
+for the sum-total of man's cerebral functions; and these are just
+as much determined by physical and chemical processes as any of the
+other vital functions, and just as amenable to the law of substance.
+The _histological_ argument is based on the extremely complicated
+microscopic structure of the brain; it shows us the true "elementary
+organs of the soul" in the ganglionic cells. The _experimental_
+argument proves that the various functions of the soul are bound up
+with certain special parts of the brain, and cannot be exercised unless
+these are in a normal condition; if the areas are destroyed, their
+function is extinguished; and this is especially applicable to the
+"organs of thought," the four central instruments of mental activity.
+The _pathological_ argument is the complement of the physiological;
+when certain parts of the brain (the centres of speech, sight,
+hearing, etc.) are destroyed by sickness, their activity (speech,
+vision, hearing, etc.) disappears; in this way nature herself makes
+the decisive physiological experiment. The _ontogenetic_ argument
+puts before us the facts of the development of the soul in the
+individual; we see how the child-soul gradually unfolds its various
+powers; the youth presents them in full bloom, the mature man shows
+their ripe fruit; in old age we see the gradual decay of the psychic
+powers, corresponding to the senile degeneration of the brain. The
+_phylogenetic_ argument derives its strength from palæontology, and the
+comparative anatomy and physiology of the brain; co-operating with and
+completing each other, these sciences prove to the hilt that the human
+brain (and, consequently, its function--the soul) has been evolved step
+by step from that of the mammal, and, still further back, from that of
+the lower vertebrate.
+
+These inquiries, which might be supplemented by many other results of
+modern science, prove the old dogma of the immortality of the soul
+to be absolutely untenable; in the twentieth century it will not be
+regarded as a subject of serious scientific research, but will be left
+wholly to transcendental "faith." The "critique of pure reason" shows
+this treasured faith to be a mere _superstition_, like the belief in a
+personal God which generally accompanies it. Yet even to-day millions
+of "believers"--not only of the lower, uneducated masses, but even of
+the most cultured classes--look on this superstition as their dearest
+possession and their most "priceless treasure." It is, therefore,
+necessary to enter more deeply into the subject, and--assuming it to
+be true--to make a critical inquiry into its practical value. It soon
+becomes apparent to the impartial critic that this value rests, for
+the most part, on fancy, on the want of clear judgment and consecutive
+thought. It is my firm and honest conviction that a definitive
+abandonment of these "athanatist illusions" would involve no painful
+loss, but an inestimable positive gain for humanity.
+
+Man's "emotional craving" clings to the belief on immortality for two
+main reasons: firstly, in the hope of better conditions of life beyond
+the grave; and, secondly, in the hope of seeing once more the dear
+and loved ones whom death has torn from us. As for the first hope,
+it corresponds to a natural feeling of the justice of compensation,
+which is quite correct subjectively, but has no objective validity
+whatever. We make our claim for an indemnity for the unnumbered defects
+and sorrows of our earthly existence, without the slightest real
+prospect or guarantee of receiving it. We long for an eternal life in
+which we shall meet no sadness and no pain, but an unbounded peace
+and joy. The pictures that most men form of this blissful existence
+are extremely curious; the immaterial soul is placed in the midst of
+grossly material pleasures. The imagination of each believer paints
+the enduring splendor according to his personal taste. The American
+Indian, whose athanatism Schiller has so well depicted, trusts to
+find in his Paradise the finest hunting-grounds with innumerable
+hordes of buffaloes and bears; the Eskimo looks forward to sun-tipped
+icebergs with an inexhaustible supply of bears, seals, and other polar
+animals; the effeminate Cingalese frames his Paradise on the wonderful
+island-paradise of Ceylon with its noble gardens and forests--adding
+that there will be unlimited supplies of rice and curry, of cocoanuts
+and other fruit, always at hand; the Mohammedan Arab believes it will
+be a place of shady gardens of flowers, watered by cool springs, and
+filled with lovely maidens; the Catholic fisherman of Sicily looks
+forward to a daily superabundance of the most valuable fishes and the
+finest macaroni, and eternal absolution for all his sins, which he
+can go on committing in his eternal home; the evangelical of North
+Europe longs for an immense Gothic cathedral, in which he can chant
+the praises of the Lord of Hosts for all eternity. In a word, each
+believer really expects his eternal life to be a direct continuation
+of his individual life on earth, only in a "much improved and enlarged
+edition."
+
+We must lay special stress on the thoroughly materialistic character
+of _Christian_ athanatism, which is closely connected with the absurd
+dogma of the "resurrection of the body." As thousands of paintings of
+famous masters inform us, the bodies that have risen again, with the
+souls that have been born again, walk about in heaven just as they did
+in this vale of tears; they see God with their eyes, they hear His
+voice with their ears, they sing hymns to His praise with their larynx,
+and so forth. In fine, the modern inhabitants of the Christian Paradise
+have the same dual character of body and soul, the same organs of an
+earthly body, as our ancient ancestors had in Odin's Hall in Walhalla,
+as the "immortal" Turks and Arabs have in Mohammed's lovely gardens, as
+the old Greek demi-gods and heroes had in the enjoyment of nectar and
+ambrosia at the table of Zeus.
+
+But, however gloriously we may depict this eternal life in Paradise,
+it remains _endless_ in duration. Do we realize what "eternity"
+means?--the uninterrupted continuance of our individual life forever!
+The profound legend of the "wandering Jew," the fruitless search for
+rest of the unhappy Ahasuerus, should teach us to appreciate such
+an "eternal life" at its true value. The best we can desire after a
+courageous life, spent in doing good according to our light, is the
+eternal peace of the grave. "Lord, give them an eternal rest."
+
+Any impartial scholar who is acquainted with geological calculations
+of time, and has reflected on the long series of millions of years the
+organic history of the earth has occupied, must admit that the crude
+notion of an eternal life is not a _comfort_, but a fearful _menace_,
+to the best of men. Only want of clear judgment and consecutive thought
+can dispute it.
+
+The best and most plausible ground for athanatism is found in the
+hope that immortality will reunite us to the beloved friends who have
+been prematurely taken from us by some grim mischance. But even this
+supposed good fortune proves to be an illusion on closer inquiry; and
+in any case it would be greatly marred by the prospect of meeting the
+less agreeable acquaintances and the enemies who have troubled our
+existence here below. Even the closest family ties would involve many
+a difficulty. There are plenty of men who would gladly sacrifice all
+the glories of Paradise if it meant the eternal companionship of their
+"better half" and their mother-in-law. It is more than questionable
+whether Henry VIII. would like the prospect of living eternally with
+his six wives; or Augustus the Strong of Poland, who had a hundred
+mistresses and three hundred and fifty-two children. As he was on good
+terms with the Vicar of Christ, he must be assumed to be in Paradise,
+in spite of his sins, and in spite of the fact that his mad military
+ventures cost the lives of more than a hundred thousand Saxons.
+
+Another insoluble difficulty faces the athanatist when he asks _in what
+stage of their individual development_ the disembodied souls will spend
+their eternal life. Will the new-born infant develop its psychic powers
+in heaven under the same hard conditions of the "struggle for life"
+which educate man here on earth? Will the talented youth who has fallen
+in the wholesale murder of war unfold his rich, unused mental powers in
+Walhalla? Will the feeble, childish old man, who has filled the world
+with the fame of his deeds in the ripeness of his age, live forever in
+mental decay? Or will he return to an earlier stage of development?
+If the immortal souls in Olympus are to live in a condition of
+rejuvenescence and perfectness, then both the stimulus to the formation
+of, and the interest in, personality disappear for them.
+
+Not less impossible, in the light of pure reason, do we find the
+anthropistic myth of the "last judgment," and the separation of the
+souls of men into two great groups, of which one is destined for
+the eternal joys of Paradise and the other for the eternal torments
+of hell--and that from a personal God who is called the "Father of
+Love"! And it is this "Universal Father" who has himself created the
+conditions of heredity and adaptation, in virtue of which the elect, on
+the one side, were _bound_ to pursue the path towards eternal bliss,
+and the luckless poor and miserable, on the other hand, were _driven_
+into the paths of the damned?
+
+A critical comparison of the countless and manifold fantasies which
+belief in immortality has produced during the last few thousand years
+in the different races and religions yields a most remarkable picture.
+An intensely interesting presentation of it, based on most extensive
+original research, may be found in Adalbert Svoboda's distinguished
+works, _The Illusion of the Soul_ and _Forms of Faith_. However absurd
+and inconsistent with modern knowledge most of these myths seem to be,
+they still play an important part, and, as "postulates of practical
+reason," they exercise a powerful influence on the opinions of
+individuals and on the destiny of races.
+
+The idealist and spiritualist philosophy of the day will freely grant
+that these prevalent materialistic forms of belief in immortality are
+untenable; it will say that the refined idea of an immaterial soul,
+a Platonic "idea" or a transcendental psychic substance, must be
+substituted for them. But modern realism can have nothing whatever to
+do with these incomprehensible notions; they satisfy neither the mind's
+feeling of causality nor the yearning of our emotions. If we take a
+comprehensive glance at all that modern anthropology, psychology,
+and cosmology teach with regard to athanatism, we are forced to this
+definite conclusion: "The belief in the immortality of the human soul
+is a dogma which is in hopeless contradiction with the most solid
+empirical truths of modern science."
+
+
+
+
+CHAPTER XII
+
+THE LAW OF SUBSTANCE
+
+    The Fundamental Chemical Law of the Constancy of Matter--The
+    Fundamental Physical Law of the Conservation of Energy--Combination
+    of Both Laws in the Law of Substance--The Kinetic, Pyknotic,
+    and Dualistic Ideas of Substance--Monism of Matter--Ponderable
+    Matter--Atoms and Elements--Affinity of the Elements--The Soul of
+    the Atom (Feeling and Inclination)--Existence and Character of
+    Ether--Ether and Ponderable Matter--Force and Energy--Potential
+    and Actual Force--Unity of Natural Forces--Supremacy of the Law of
+    Substance
+
+
+The supreme and all-pervading law of nature, the true and only
+cosmological law, is, in my opinion, _the law of substance_; its
+discovery and establishment is the greatest intellectual triumph of the
+nineteenth century, in the sense that all other known laws of nature
+are subordinate to it. Under the name of "law of substance" we embrace
+two supreme laws of different origin and age--the older is the chemical
+law of the "conservation of matter," and the younger is the physical
+law of the "conservation of energy."[23] It will be self-evident to
+many readers, and it is acknowledged by most of the scientific men of
+the day, that these two great laws are essentially inseparable. This
+fundamental thesis, however, is still much contested in some quarters,
+and we must proceed to furnish the proof of it. But we must first
+devote a few words to each of the two laws.
+
+The law of the "_persistence_" or "_indestructibility of matter_,"
+established by Lavoisier in 1789, may be formulated thus: The sum of
+matter, which fills infinite space, is unchangeable. A body has merely
+changed its form, when it seems to have disappeared. When coal burns,
+it is changed into carbonic-acid gas by combination with the oxygen of
+the atmosphere; when a piece of sugar melts in water, it merely passes
+from the solid to the fluid condition. In the same way, it is merely
+a question of change of form in the cases where a new body seems to
+be produced. A shower of rain is the moisture of the atmosphere cast
+down in the form of drops of water; when a piece of iron rusts, the
+surface layer of the metal has combined with water and with atmospheric
+oxygen, and formed a "rust," or oxyhydrate of iron. Nowhere in nature
+do we find an example of the production, or "creation," of new matter;
+nowhere does a particle of existing matter pass entirely away. This
+empirical truth is now the unquestionable foundation of chemistry; it
+may be directly verified at any moment by means of the balance. To the
+great French chemist Lavoisier belongs the high merit of first making
+this experiment with the balance. At the present day the scientist, who
+is occupied from one end of the year to the other with the study of
+natural phenomena, is so firmly convinced of the absolute "constancy"
+of matter that he is no longer able to imagine the contrary state of
+things.
+
+We may formulate the "_law of the persistence of force_" or
+"_conservation of energy_" thus: The sum of force, which is at work in
+infinite space and produces all phenomena, is unchangeable. When the
+locomotive rushes along the line, the potential energy of the steam
+is transformed into the kinetic or actual energy of the mechanical
+movement; when we hear its shrill whistle, as it speeds along, the
+sound-waves of the vibrating atmosphere are conveyed through the
+tympanum and the three bones of the ear into the inner labyrinth, and
+thence transferred by the auditory nerve to the acoustic ganglionic
+cells which form the centre of hearing in the temporal lobe of the
+gray bed of the brain. The whole marvellous panorama of life that
+spreads over the surface of our globe is, in the last analysis,
+transformed sunlight. It is well known how the remarkable progress of
+technical science has made it possible for us to convert the different
+physical forces from one form to another; heat may be changed into
+molar movement, or movement of mass; this in turn into light or sound,
+and then into electricity, and so forth. Accurate measurement of
+the quantity of force which is used in this metamorphosis has shown
+that it is "constant" or unchanged. No particle of living energy is
+ever extinguished; no particle is ever created anew. Friedrich Mohr,
+of Bonn, was very near to the discovery of this great fact in 1837,
+but the discovery was actually made by the able Swabian physician,
+Robert Mayer, of Heilbronn, in 1842. Independently of Mayer, however,
+the principle was reached almost at the same time by the famous
+physiologist, Hermann Helmholtz; five years afterwards he pointed out
+its general application to, and fertility in, every branch of physics.
+We ought to say to-day that it rules also in the entire province of
+physiology--that is, of "organic physics"; but on that point we meet
+a strenuous opposition from the vitalistic biologists and the dualist
+and spiritualist philosophers. For these the peculiar "spiritual
+forces" of human nature are a group of "free" forces, not subject to
+the law of energy; the idea is closely connected with the dogma of the
+"freedom of the will." We have, however, already seen (p. 204) that the
+dogma is untenable. Modern physics draws a distinction between "force"
+and "energy," but our general observations so far have not needed a
+reference to it.
+
+The conviction that these two great cosmic theorems, the chemical law
+of the persistence of matter and the physical law of the persistence
+of force, are fundamentally one, is of the utmost importance in our
+monistic system. The two theories are just as intimately united as
+their objects--matter and force or energy. Indeed, this fundamental
+unity of the two laws is self-evident to many monistic scientists and
+philosophers, since they merely relate to two different aspects of one
+and the same object, the _cosmos_. But, however natural the thought may
+be, it is still very far from being generally accepted. It is stoutly
+contested by the entire dualistic philosophy, vitalistic biology,
+and parallelistic psychology; even, in fact, by a few (inconsistent)
+monists, who think they find a check to it in "consciousness," in the
+higher mental activity of man, or in other phenomena of our "free
+mental life."
+
+For my part, I am convinced of the profound importance of the unifying
+"law of substance," as an expression of the inseparable connection in
+reality of two laws which are only separated in conception. That they
+were not originally taken together and their unity recognized from
+the beginning is merely an accident of the date of their respective
+discoveries. The earlier and more accessible chemical law of the
+persistence of matter was detected by Lavoisier in 1789, and, after
+a general application of the balance, became the basis of exact
+chemistry. On the other hand, the more recondite law of the persistence
+of force was only discovered by Mayer in 1842, and only laid down
+as the basis of exact physics by Helmholtz. The unity of the two
+laws--still much disputed--is expressed by many scientists who are
+convinced of it in the formula: "Law of the persistence of matter and
+force." In order to have a briefer and more convenient expression for
+this fundamental thought, I proposed some time ago to call it the "law
+of substance" or the "fundamental cosmic law"; it might also be called
+the "universal law," or the "law of constancy," or the "axiom of the
+constancy of the universe." In the ultimate analysis it is found to be
+a necessary consequence of the principle of causality.[24]
+
+The first thinker to introduce the purely monistic conception of
+substance into science and appreciate its profound importance was the
+great philosopher Baruch Spinoza; his chief work appeared shortly after
+his premature death in 1677, just one hundred years before Lavoisier
+gave empirical proof of the constancy of matter by means of the
+chemist's principal instrument, the balance. In his stately pantheistic
+system the notion of the _world_ (the universe, or the cosmos) is
+identical with the all-pervading notion of God; it is at one and the
+same time the purest and most rational _monism_ and the clearest and
+most abstract _monotheism_. This universal substance, this "divine
+nature of the world," shows us two different aspects of its being, or
+two fundamental attributes--matter (infinitely _extended_ substance)
+and spirit (the all-embracing energy of _thought_). All the changes
+which have since come over the idea of substance are reduced, on a
+logical analysis, to this supreme thought of Spinoza's; with Goethe
+I take it to be the loftiest, profoundest, and truest thought of all
+ages. Every single object in the world which comes within the sphere
+of our cognizance, all individual forms of existence, are but special
+transitory forms--_accidents_ or _modes_--of substance. These modes are
+material things when we regard them under the attribute of _extension_
+(or "occupation of space"), but forces or ideas when we consider them
+under the attribute of _thought_ (or "energy"). To this profound
+thought of Spinoza our purified monism returns after a lapse of two
+hundred years; for us, too, matter (space-filling substance) and energy
+(moving force) are but two inseparable attributes of the one underlying
+substance.
+
+Among the various modifications which the fundamental idea of substance
+has undergone in modern physics, in association with the prevalent
+atomism, we shall select only two of the most divergent theories for
+a brief discussion, the kinetic and the pyknotic. Both theories agree
+that we have succeeded in reducing all the different forces of nature
+to one common original force; gravity and chemical action, electricity
+and magnetism, light and heat, etc., are only different manifestations,
+forms, or _dynamodes_, of a single primitive force (_prodynamis_).
+This fundamental force is generally conceived as a vibratory motion
+of the smallest particles of matter--a vibration of atoms. The atoms
+themselves, according to the usual "kinetic theory of substance," are
+dead, separate particles of matter, which dance to and fro in empty
+space and act at a distance. The real founder and most distinguished
+representative of the kinetic theory is Newton, the famous discoverer
+of the law of gravitation. In his great work, the _Philosophiae
+Naturalis Principia Mathematica_ (1687), he showed that throughout the
+universe the same law of attraction controls the unvarying constancy of
+gravitation; the attraction of two particles being in direct proportion
+to their mass and in inverse proportion to the square of their
+distance. This universal force of gravity is at work in the fall of
+an apple and the tidal wave no less than in the course of the planets
+round the sun and the movements of all the heavenly bodies. Newton
+had the immortal merit of establishing the law of gravitation and
+embodying it in an indisputable mathematical formula. Yet this _dead
+mathematical formula_, on which most scientists lay great stress, as so
+frequently happens, gives us merely the _quantitative_ demonstration
+of the theory; it gives us no insight whatever into the _qualitative_
+nature of the phenomena. The action at a distance without a medium,
+which Newton deduced from his law of gravitation, and which became one
+of the most serious and most dangerous dogmas of later physics, does
+not afford the slightest explanation of the real causes of attraction;
+indeed, it long obstructed our way to the real discovery of them. I
+cannot but suspect that his speculations on this mysterious action at a
+distance contributed not a little to the leading of the great English
+mathematician into the obscure labyrinth of mystic dreams and theistic
+superstition in which he passed the last thirty-four years of his
+life; we find him, at the end, giving metaphysical hypotheses on the
+predictions of Daniel and on the paradoxical fantasies of St. John.
+
+In fundamental opposition to the theory of vibration, or the kinetic
+theory of substance, we have the modern "theory of condensation,"
+or the pyknotic theory of substance. It is most ably established
+in the suggestive work of J. C. Vogt on _The Nature of Electricity
+and Magnetism on the Basis of a Simplified Conception of Substance_
+(1891). Vogt assumes the primitive force of the world, the universal
+_prodynamis_, to be, not the vibration or oscillation of particles in
+empty space, but the condensation of a simple primitive substance,
+which fills the infinity of space in an unbroken continuity. Its
+sole inherent mechanical form of activity consists in a tendency to
+condensation or contraction, which produces infinitesimal centres
+of condensation; these may change their degree of thickness, and,
+therefore, their volume, but are constant as such. These minute parts
+of the universal substance, the centres of condensation, which might
+be called _pyknatoms_, correspond in general to the ultimate separate
+atoms of the kinetic theory; they differ, however, very considerably in
+that they are credited with sensation and inclination (or will-movement
+of the simplest form), _with souls_, in a certain sense--in harmony
+with the old theory of Empedocles of the "love and hatred of the
+elements." Moreover, these "atoms with souls" do not float in empty
+space, but in the continuous, extremely attenuated intermediate
+substance, which represents the uncondensed portion of the primitive
+matter. By means of certain "constellations, centres of perturbation,
+or systems of deformation," great masses of centres of condensation
+quickly unite in immense proportions, and so obtain a preponderance
+over the surrounding masses. By that process the primitive substance,
+which in its original state of quiescence had the same mean consistency
+throughout, divides or differentiates into two kinds. The centres
+of disturbance, which _positively_ exceed the mean consistency in
+virtue of the _pyknosis_ or condensation, form the ponderable matter
+of bodies; the finer, intermediate substance, which occupies the space
+between them, and _negatively_ falls below the mean consistency, forms
+the ether, or imponderable matter. As a consequence of this division
+into mass and ether there ensues a ceaseless struggle between the two
+antagonistic elements, and this struggle is the source of all physical
+processes. The positive ponderable matter, the element with the feeling
+of like or desire, is continually striving to complete the process of
+condensation, and thus collecting an enormous amount of _potential_
+energy; the negative, imponderable matter, on the other hand, offers a
+perpetual and equal resistance to the further increase of its strain
+and of the feeling of dislike connected therewith, and thus gathers the
+utmost amount of _actual_ energy.
+
+We cannot go any further here into the details of the brilliant
+theory of J. C. Vogt. The interested reader cannot do better than
+have recourse to the second volume of the above work for a clear,
+popular exposition of the difficult problem. I am myself too little
+informed in physics and mathematics to enter into a critical discussion
+of its lights and shades; still, I think that this pyknotic theory
+of substance will prove more acceptable to every biologist who is
+convinced of the unity of nature than the kinetic theory which prevails
+in physics to-day. A misunderstanding may easily arise from the fact
+that Vogt puts his process of condensation in explicit contradiction
+with the general phenomenon of motion; but it must be remembered that
+he is speaking of vibratory movement in the sense of the physicist. His
+hypothetical "condensation" is just as much determined by a movement
+of substance as is the hypothetical "vibration"; only the kind of
+movement and the relation of the moving elements are very different in
+the two hypotheses. Moreover, it is not the whole theory of vibration,
+but only an important section of it, that is contradicted by the theory
+of condensation.
+
+Modern physics, for the most part, still firmly adheres to the older
+theory of vibration, to the idea of an _actio in distans_ and the
+eternal vibration of dead atoms in empty space; it rejects the pyknotic
+theory. Although Vogt's theory may be still far from perfect, and his
+original speculations may be marred by many errors, yet I think he has
+rendered a very good service in eliminating the untenable principles
+of the kinetic theory of substance. As to my own opinion--and that of
+many other scientists--I must lay down the following theses, which
+are involved in Vogt's pyknotic theory, as indispensable for a truly
+monistic view of substance, and one that covers the whole field of
+organic and inorganic nature:
+
+I. The two fundamental forms of substance, ponderable matter and ether,
+are not dead and only moved by extrinsic force, but they are endowed
+with sensation and will (though, naturally, of the lowest grade); they
+experience an inclination for condensation, a dislike of strain; they
+strive after the one and struggle against the other.
+
+II. There is no such thing as empty space; that part of space which is
+not occupied with ponderable atoms is filled with ether.
+
+III. There is no such thing as an action at a distance through
+perfectly empty space; all action of bodies upon each other is either
+determined by immediate contact or is effected by the mediation of
+ether.
+
+Both the theories of substance which we have just contrasted are
+_monistic_ in principle, since the opposition between the two
+conditions of substance--mass and ether--is not original; moreover,
+they involve a continuous immediate contact and reciprocal action
+of the two elements. It is otherwise with the _dualistic_ theories
+of substance which still obtain in the idealist and spiritualist
+philosophy, and which have the support of a powerful theology, in so
+far as theology indulges in such metaphysical speculations. These
+theories draw a distinction between two entirely different kinds of
+substance, material and immaterial. Material substance enters into
+the composition of the bodies which are the object of physics and
+chemistry; the law of the persistence of matter and force is confined
+to this world (apart from a belief in its "creation from nothing"
+and other miracles). Immaterial substance is found in the "spiritual
+world" to which the law does not extend; in this province the laws
+of physics and chemistry are either entirely inapplicable or they
+are subordinated to a "vital force," or a "free will," or a "divine
+omnipotence," or some other phantom which is beyond the ken of critical
+science. In truth, these profound errors need no further refutation
+to-day, for experience has never yet discovered for us a single
+immaterial substance, a single force which is not dependent on matter,
+or a single form of energy which is not exerted by material movement,
+whether it be of mass, or of ether, or of both. Even the most elaborate
+and most perfect forms of energy that we know--the psychic life of
+the higher animals, the thought and reason of man--depend on material
+processes, or changes in the neuroplasm of the ganglionic cells; they
+are inconceivable apart from such modifications. I have already shown
+(chap. xi.) that the physiological hypothesis of a special, immaterial
+"soul-substance" is untenable.
+
+The study of ponderable matter is primarily the concern of chemistry.
+Few are ignorant of the astonishing theoretical progress which this
+science has made in the course of the century and the immense practical
+influence it has had on every aspect of modern life. We shall confine
+ourselves here to a few remarks on the more important questions
+which concern the nature of ponderable matter. It is well known that
+analytical chemistry has succeeded in resolving the immense variety
+of bodies in nature into a small number of simple elements--that is,
+simple bodies which are incapable of further analysis. The number of
+these elements is about seventy. Only fourteen of them are widely
+distributed on the earth and of much practical importance; the majority
+are rare elements (principally metals) of little practical moment. The
+affinity of these groups of elements, and the remarkable proportions of
+their atomic weights, which Lothar Meyer and Mendelejeff have proved
+in their _Periodic System of the Elements_, make it extremely probable
+that they are not _absolute species_ of ponderable matter--that is,
+not eternally unchangeable particles. The seventy elements have in
+that system been distributed into eight leading groups, and arranged
+in them according to their atomic weight, so that the elements which
+have a chemical affinity are formed into families. The relations of
+the various groups in such a natural system of the elements recall,
+on the one hand, similar relations of the innumerable compounds of
+carbon, and, again, the relations of parallel groups in the natural
+arrangement of the animal and plant species. Since in the latter
+cases the "affinity" of the related forms is based on descent from a
+common parent form, it seems very probable that the same holds good of
+the families and orders of the chemical elements. We may, therefore,
+conclude that the "empirical elements" we now know are not really
+simple, ultimate, and unchangeable forms of matter, but compounds
+of homogeneous, simple, primitive atoms, variously distributed as
+to number and grouping. The recent speculations of Gustav Wendt,
+Wilhelm Preyer, Sir W. Crookes, and others, have pointed out how we
+may conceive the evolution of the elements from a simple primitive
+material, the _prothyl_.
+
+The modern atomistic theory, which is regarded as an indispensable
+instrument in chemistry to-day, must be carefully distinguished from
+the old philosophic atomism which was taught more than two thousand
+years ago by a group of distinguished thinkers of antiquity--Leucippus,
+Democritus, and Epicurus: it was considerably developed and modified
+later on by Descartes, Hobbes, Leibnitz, and other famous philosophers.
+But it was not until 1808 that modern atomism assumed a definite and
+acceptable form, and was furnished with an empirical basis by Dalton,
+who formulated the "law of simple and multiple proportions" in the
+formation of chemical combinations. He first determined the atomic
+weight of the different elements, and thus created the solid and exact
+foundation on which more recent chemical theories are based; these
+are all _atomistic_, in the sense that they assume the elements to be
+made up of homogeneous, infinitesimal, distinct particles, which are
+incapable of further analysis. That does not touch the question of the
+real nature of the atoms--their form, size, psychology, etc. These
+atomic qualities are merely hypothetical; while the _chemistry_ of the
+atoms, their "chemical affinity"--that is, the constant proportion in
+which they combine with the atoms of other elements--is empirical.[25]
+
+The different relation of the various elements towards each other,
+which chemistry calls "affinity," is one of the most important
+properties of ponderable matter; it is manifested in the different
+relative quantities or proportions of their combination in the
+intensity of its consummation. Every shade of inclination, from
+complete indifference to the fiercest passion, is exemplified in the
+chemical relation of the various elements towards each other, just
+as we find in the psychology of man, and especially in the life of
+the sexes. Goethe, in his classical romance, _Affinities_, compared
+the relations of pairs of lovers with the phenomenon of the same name
+in the formation of chemical combinations. The irresistible passion
+that draws Edward to the sympathetic Ottilia, or Paris to Helen, and
+leaps over all bounds of reason and morality, is the same powerful
+"unconscious" attractive force which impels the living spermatozoon to
+force an entrance into the ovum in the fertilization of the egg of the
+animal or plant--the same impetuous movement which unites two atoms
+of hydrogen to one atom of oxygen for the formation of a molecule of
+water. This fundamental _unity of affinity in the whole of nature_,
+from the simplest chemical process to the most complicated love story,
+was recognized by the great Greek scientist, Empedocles, in the fifth
+century B.C., in his theory of "the love and hatred of the elements."
+It receives empirical confirmation from the interesting progress of
+cellular psychology, the great significance of which we have only
+learned to appreciate in the last thirty years. On those phenomena we
+base our conviction that even the _atom_ is not without a rudimentary
+form of sensation and will, or as it is better expressed, of feeling
+(_aesthesis_) and inclination (_tropesis_)--that is, a universal "soul"
+of the simplest character. The same must be said of the molecules which
+are composed of two or more atoms. Further combinations of different
+kinds of these molecules give rise to simple and, subsequently, complex
+chemical compounds, in the activity of which the same phenomena are
+repeated in a more complicated form.
+
+The study of ether, or imponderable matter, pertains principally to
+physics. The existence of an extremely attenuated medium, filling the
+whole of space outside of ponderable matter, was known and applied
+to the elucidation of various phenomena (especially light) a long
+time ago; but it was not until the second half of the nineteenth
+century that we became more closely acquainted with this remarkable
+substance, in connection with our astonishing empirical discoveries in
+the province of electricity, with their experimental detection, their
+theoretical interpretation, and their practical application. The path
+was opened in particular by the famous researches of Heinrich Hertz, of
+Bonn, in 1888. The premature death of a brilliant young physicist of so
+much promise cannot be sufficiently deplored. Like the premature death
+of Spinoza, Raphael, Schubert, and many other great men, it is one of
+those brutal facts of human history which are enough of themselves to
+destroy the untenable myth of a "wise Providence" and an "All-loving
+Father in heaven."
+
+The existence of ether (or cosmic ether) as a real element is a
+_positive fact_, and has been known as such for the last twelve years.
+We sometimes read even to-day that ether is a "pure hypothesis";
+this erroneous assertion comes not only from uninformed philosophers
+and "popular" writers, but even from certain "prudent and exact
+physicists." But there would be just as much reason to deny the
+existence of ponderable matter. As a matter of fact, there are
+metaphysicians who accomplish even this feat, and whose highest wisdom
+lies in denying or calling into question the existence of an external
+universe; according to them only one real entity exists--their own
+precious personality, or, to be more correct, their immortal soul.
+Several modern physiologists have embraced this ultra-idealist view,
+which is to be found in Descartes, Berkeley, Fichte, and others.
+Their "psycho-monism" affirms: "One thing only exists, and that is
+my own mind." This audacious spiritualism seems to us to rest on an
+erroneous inference from Kant's correct critical theory, that we can
+know the outer world only in the phenomenal aspect which is accessible
+to our human organs of thought--the brain and the organs of sense. If
+by those means we can attain only an imperfect and limited knowledge
+of the material world, that is no reason for denying its existence
+altogether. In my opinion, the existence of ether is as certain as that
+of ponderable matter--as certain as my own existence, as I reflect and
+write on it. As we assure ourselves of the existence of ponderable
+matter by its mass and weight, by chemical and mechanical experiments,
+so we prove that of ether by the experiences and experiments of optics
+and electricity.
+
+Although, however, the existence of ether is now regarded as a
+positive fact by nearly all physicists, and although many effects of
+this remarkable substance are familiar to us through an extensive
+experience, especially in the way of optical and electrical experiments,
+yet we are still far from being clear and confident as to its real
+character. The views of the most eminent physicists, who have made
+a special study of it, are extremely divergent; they frequently
+contradict each other on the most important points. One is, therefore,
+free to choose among the contradictory hypotheses according to one's
+knowledge and judgment. I will put in the following eight theses the
+view which has approved itself to me after mature reflection on the
+subject, though I am no expert in this department:
+
+I. Ether fills the whole of space, in so far as it is not occupied by
+ponderable matter, as a _continuous substance_; it fully occupies the
+space between the atoms of ponderable matter.
+
+II. Ether has probably no chemical quality, and is not composed of
+atoms. If it be supposed that it consists of minute homogeneous atoms
+(for instance, indivisible etheric particles of a uniform size), it
+must be further supposed that there is something else between these
+atoms, either "empty space" or a third, completely unknown medium, a
+purely hypothetical "interether"; the question as to the nature of this
+brings us back to the original difficulty, and so on _in infinitum_.
+
+III. As the idea of an empty space and an action at a distance is
+scarcely possible in the present condition of our knowledge (at least
+it does not help to a clear monistic view), I postulate for ether a
+special structure which is not atomistic, like that of ponderable
+matter, and which may provisionally be called (without further
+determination) _etheric_ or _dynamic_ structure.
+
+IV. The consistency of ether is also peculiar, on our hypothesis, and
+different from that of ponderable matter. It is neither gaseous, as
+some conceive, nor solid, as others suppose; the best idea of it can be
+formed by comparison with an extremely attenuated, elastic, and light
+jelly.
+
+V. Ether may be called _imponderable_ matter in the sense that we
+have no means of determining its weight experimentally. If it really
+has weight, as is very probable, it must be so slight as to be far
+below the capacity of our most delicate balance. Some physicists have
+attempted to determine its weight by the energy of the light-waves, and
+have discovered that it is some fifteen trillion times lighter than
+atmospheric air; on that hypothesis a sphere of ether of the size of
+our earth would weigh at least two hundred and fifty pounds(?).
+
+VI. The etheric consistency may probably (in accordance with the
+pyknotic theory) pass into the gaseous state under certain conditions
+by progressive condensation, just as a gas may be converted into a
+fluid, and ultimately into a solid, by lowering its temperature.
+
+VII. Consequently, these three conditions of matter may be arranged
+(and it is a point of great importance in our monistic cosmogony) in a
+genetic, continuous order. We may distinguish five stages in it: (1)
+the etheric, (2) the gaseous, (3) the fluid, (4) the viscous (in the
+living protoplasm), and (5) the solid state.
+
+VIII. Ether is boundless and immeasurable, like the space it occupies.
+It is in eternal motion; and this specific movement of ether (it is
+immaterial whether we conceive it as vibration, strain, condensation,
+etc.), in reciprocal action with mass-movement (or gravitation), is the
+ultimate cause of all phenomena.
+
+"The great question of the nature of ether," as Hertz justly calls
+it, includes the question of its relation to ponderable matter; for
+these two forms of matter are not only always in the closest external
+contact, but also in eternal, dynamic, reciprocal action. We may divide
+the most general phenomena of nature, which are distinguished by
+physics as natural forces or "functions of matter," into two groups;
+the first of them may be regarded mainly (though not exclusively) as a
+function of ether, and the second a function of ponderable matter--as
+in the following scheme which I take from my _Monism_:
+
+ THE WORLD (NATURE, OR THE COSMOS)
+
+ ---------------------------------+-------------------------------------
+  ETHER--Imponderable.            | MASS--Ponderable.
+ ---------------------------------+-------------------------------------
+                                  |
+ 1. _Consistency_:                | 1. _Consistency_:
+                                  |
+ Etheric (_i.e._, neither         | Not etheric (but gaseous, fluid,
+ gaseous nor fluid, nor solid).   | or solid).
+                                  |
+ 2. _Structure_:                  | 2. _Structure_:
+                                  |
+ Not atomistic, not made up of    | Atomistic, made up of infinitesimal,
+ separate particles (atoms), but  | distinct particles (atoms)
+ continuous.                      | discontinuous.
+                                  |
+ 3. _Chief Functions_:            | 3. _Chief Functions_:
+                                  |
+ Light, radiant heat, electricity,| Gravity, inertia, molecular heat,
+ and magnetism.                   | and chemical affinity.
+ ---------------------------------+-------------------------------------
+
+The two groups of functions of matter, which we have opposed in this
+table, may, to some extent, be regarded as the outcome of the first
+"division of labor" in the development of matter, the "primary ergonomy
+of matter." But this distinction must not be supposed to involve an
+absolute separation of the two antithetic groups; they always retain
+their connection, and are in constant reciprocal action. It is well
+known that the optical and electrical phenomena of ether are closely
+connected with mechanical and chemical changes in ponderable elements;
+the radiant heat of ether may be directly converted into the mechanical
+heat of the mass; gravitation is impossible unless the ether effects
+the mutual attraction of the separated atoms, because we cannot admit
+the idea of an _actio in distans_. In like manner, the conversion
+of one form of energy into another, as indicated in the law of the
+persistence of force, illustrates the constant reciprocity of the two
+chief types of substance, ether and mass.
+
+The great law of nature, which, under the title of the "law of
+substance," we put at the head of all physical considerations, was
+conceived as the law of "the persistence of force" by Robert Meyer, who
+first formulated it, and Helmholtz, who continued the work. Another
+German scientist, Friedrich Mohr, of Bonn, had clearly outlined it in
+its main features ten years earlier (1837). The old idea of _force_
+was, after a time, differentiated by modern physics from that of
+_energy_, which was at first synonymous with it. Hence the law is
+now usually called the "law of the persistence of energy." However,
+this finer distinction need not enter into the general consideration,
+to which I must confine myself here, and into the question of the
+great principle of the "persistence of substance." The interested
+reader will find a very clear treatment of the question in Tyndall's
+excellent paper on "The Fundamental Law of Nature," in his _Fragments
+of Science_. It fully explains the broad significance of this profound
+cosmic law, and points out its application to the main problems of
+very different branches of science. We shall confine our attention to
+the important fact that the "principle of energy" and the correlative
+idea of the unity of natural forces, on the basis of a common origin,
+are now accepted by all competent physicists, and are regarded as the
+greatest advance of physics in the nineteenth century. We now know that
+heat, sound, light, chemical action, electricity, and magnetism are all
+modes of motion. We can, by a certain apparatus, convert any one of
+these forces into another, and prove by an accurate measurement that
+not a single particle of energy is lost in the process.
+
+The sum-total of force or energy in the universe remains constant, no
+matter what changes take place around us; it is eternal and infinite,
+like the matter on which it is inseparably dependent. The whole drama
+of nature apparently consists in an alternation of movement and
+repose; yet the bodies at rest have an inalienable quantity of force,
+just as truly as those that are in motion. It is in this movement
+that the potential energy of the former is converted into the kinetic
+energy of the latter. "As the principle of the persistence of force
+takes into account repulsion as well as attraction, it affirms that
+the mechanical value of the potential energy and the kinetic energy
+in the material world is a constant quantity. To put it briefly, the
+force of the universe is divided into two parts, which may be mutually
+converted, according to a fixed relation of value. The diminution of
+the one involves the increase of the other; the total value remains
+unchanged in the universe." The potential energy and the actual, or
+kinetic, energy are being continually transformed from one condition to
+the other; but the infinite sum of force in the world at large never
+suffers the slightest curtailment.
+
+Once modern physics had established the law of substance as far as
+the simpler relations of inorganic bodies are concerned, physiology
+took up the story, and proved its application to the entire province
+of the organic world. It showed that all the vital activities of the
+organism--without exception--are based on a constant "reciprocity
+of force" and a correlative change of material, or metabolism, just
+as much as the simplest processes in "lifeless" bodies. Not only
+the growth and the nutrition of plants and animals, but even their
+functions of sensation and movement, their sense-action and psychic
+life, depend on the conversion of potential into kinetic energy,
+and _vice versâ_. This supreme law dominates also those elaborate
+performances of the nervous system which we call, in the higher animals
+and man, "the action of the mind."
+
+Our monistic view, that the great cosmic law applies throughout the
+whole of nature, is of the highest moment. For it not only involves,
+on its positive side, the essential unity of the cosmos and the
+causal connection of all phenomena that come within our cognizance,
+but it also, in a negative way, marks the highest intellectual
+progress, in that it definitely rules out the three central dogmas of
+metaphysics--God, freedom, and immortality. In assigning mechanical
+causes to phenomena everywhere, the law of substance comes into line
+with the universal law of causality.
+
+
+
+
+CHAPTER XIII
+
+THE EVOLUTION OF THE WORLD
+
+    The Notion of Creation--Miracles--Creation of the Whole Universe
+    and of its Various Parts--Creation of Substance (Cosmological
+    Creation)--Deism: One Creative Day--Creation of Separate
+    Entities--Five Forms of Ontological Creationism--Theory of
+    Evolution--I. Monistic Cosmogony--Beginning and End of the
+    World--The Infinity and Eternity of the Universe--Space and
+    Time--_Universum perpetuum mobile_--Entropy of the Universe--II.
+    Monistic Geogeny--History of the Inorganic and Organic Worlds--III.
+    Monistic Biogeny--Transformism and the Theory of Descent: Lamarck
+    and Darwin--IV. Monistic Anthropogeny--Origin of Man
+
+
+The greatest, vastest, and most difficult of all cosmic problems is
+that of the origin and development of the world--the "question of
+creation," in a word. Even to the solution of this most difficult
+world-riddle the nineteenth century has contributed more than all its
+predecessors; in a certain sense, indeed, it has found the solution. We
+have at least attained to a clear view of the fact that all the partial
+questions of creation are indivisibly connected, that they represent
+one single, comprehensive "cosmic problem," and that the key to this
+problem is found in the one magic word--evolution. The great questions
+of the creation of man, the creation of the animals and plants, the
+creation of the earth and the sun, etc., are all parts of the general
+question, What is the origin of the whole world? Has it been _created_
+by supernatural power, or has it been _evolved_ by a natural process?
+What are the causes and the manner of this evolution? If we succeed
+in finding the correct answer to one of these questions, we have,
+according to our monistic conception of the world, cast a brilliant
+light on the solution of them all, and on the entire cosmic problem.
+
+The current opinion as to the origin of the world in earlier ages was
+almost a universal belief in creation. This belief has been expressed
+in thousands of interesting, more or less fabulous, legends, poems,
+cosmogonies, and myths. A few great philosophers were devoid of it,
+especially those remarkable free-thinkers of classical antiquity who
+first conceived the idea of natural evolution. All the creation-myths,
+on the contrary, were of a supernatural, miraculous, and transcendental
+character. Incompetent, as it was, to investigate for itself the
+nature of the world and its origin by natural causes, the undeveloped
+mind naturally had recourse to the idea of miracle. In most of these
+creation-myths _anthropism_ was blended with the belief in the
+miraculous. The creator was supposed to have constructed the world on a
+definite plan, just as man accomplishes his artificial constructions;
+the conception of the creator was generally completely anthropomorphic,
+a palpable "anthropistic creationism." The "all-mighty maker of heaven
+and earth," as he is called in Genesis and the Catechism, is just as
+humanly conceived as the modern creator of Agassiz and Reinke, or the
+intelligent "engineer" of other recent biologists.
+
+Entering more fully into the notion of creation, we can distinguish
+as two entirely different acts the production of the universe as a
+whole and the partial production of its various parts, in harmony with
+Spinoza's idea of _substance_ (the universe) and _accidents_ (or
+_modes_, the individual phenomena of substance). This distinction is of
+great importance, because there are many eminent philosophers who admit
+the one and reject the other.
+
+According to this creationist theory, then, God has "made the world
+out of nothing." It is supposed that God (a rational, but immaterial,
+being) existed by himself for an eternity before he resolved to create
+the world. Some supporters of the theory restrict God's creative
+function to one single act; they believe that this extramundane God
+(the rest of whose life is shrouded in mystery) created the substance
+of the world in a single moment, endowed it with the faculty of
+the most extensive evolution, and troubled no further about it.
+This view may be found, for instance, in the English Deists in many
+forms. It approaches very close to our monistic theory of evolution,
+only abandoning it in the one instant in which God accomplished the
+creation. Other creationists contend that God did not confine himself
+to the mere creation of matter, but that he continues to be operative
+as the "sustainer and ruler of the world." Different modifications of
+this belief are found, some approaching very close to _pantheism_ and
+others to complete _theism_. All these and similar forms of belief in
+creation are incompatible with the law of the persistence of matter and
+force; that law knows nothing of a beginning.
+
+It is interesting to note that E. du Bois-Reymond has identified
+himself with this cosmological creationism in his latest speech
+(on "Neovitalism," 1894). "It is more consonant with the divine
+omnipotence," he says, "to assume that it created the whole material
+of the world in one creative act unthinkable ages ago in such
+wise that it should be endowed with inviolable laws to control the
+origin and the progress of living things--that, for instance, here
+on earth rudimentary organisms should arise from which, without
+further assistance, the whole of living nature could be evolved, from
+a primitive bacillus to the graceful palm-wood, from a primitive
+micrococcus to Solomon's lovely wives or to the brain of Newton.
+Thus we are content with _one_ creative day, and we derive organic
+nature mechanically, without the aid of either old or new vitalism."
+Du Bois-Reymond here shows, as in the question of consciousness, the
+shallow and illogical character of his monistic thought.
+
+According to another still prevalent theory, which may be called
+"ontological creationism," God not only created the world at large,
+but also its separate contents. In the Christian world the old Semitic
+legend of creation, taken from Genesis, is still very widely accepted;
+even among modern scientists it finds an adherent here and there. I
+have fully entered into the criticism of it in the first chapter of my
+_Natural History of Creation_. The following theories may be enumerated
+as the most interesting modifications of this ontological creationism:
+
+I. _Dualistic creation._--God restricted his interference to _two_
+creative acts. First he created the inorganic world, mere dead
+substance, to which alone the law of energy applies, working blindly
+and aimlessly in the mechanism of material things and the building of
+the mountains; then God attained intelligence and communicated it to
+the purposive intelligent forces which initiate and control organic
+evolution.[26]
+
+II. _Trialistic creation._--God made the world in _three_ creative
+acts: (_a_) the creation of the heavens--the extra-terrestrial world,
+(_b_) the creation of the earth (as the centre of the world) and of
+its living inhabitants, and (_c_) the creation of man (in the image
+and likeness of God). This dogma is still widely prevalent among
+theologians and other "educated" people; it is taught as the truth in
+many of our schools.
+
+III. _Heptameral creation_; a creation in seven days (_teste_
+Moses).--Although few educated people really believe in this Mosaic
+myth now, it is still firmly impressed on our children in the biblical
+lessons of their earliest years. The numerous attempts that have been
+made, especially in England, to harmonize it with the modern theory of
+evolution have entirely failed. It obtained some importance in science
+when Linné adopted it in the establishment of his system, and based his
+definition of organic species (which he considered to be unchangeable)
+on it: "There are as many different species of animals and plants as
+there were different forms created in the beginning by the Infinite."
+This dogma was pretty generally held until the time of Darwin (1859),
+although Lamarck had already proved its untenability in 1809.
+
+IV. _Periodic creation._--At the beginning of each period of the
+earth's history the whole population of animals and plants was created
+anew, and destroyed by a general catastrophe at its close; there were
+as many general creative acts as there are distinct geological periods
+(the catastrophic theory of Cuvier [1818] and Louis Agassiz [1858]).
+Palæontology, which seemed to support this theory in its more imperfect
+stage, has since completely refuted it.
+
+V. _Individual creation._--Every single man--and every individual
+animal and plant--does not arise by a natural process of growth, but
+is created by the favor of God. This view of creation is still often
+met with in journals, especially in the "births" column. The special
+talents and features of our children are often gratefully acknowledged
+to be "gifts of God"; their hereditary defects fit into another theory.
+
+The error of these creation-legends and the cognate belief in miracles
+must have been apparent to thoughtful minds at an early period; more
+than two thousand years ago we find that many attempts were made
+to replace them by a rational theory, and to explain the origin of
+the world by natural causes. In the front rank, once more, we must
+place the leaders of the Ionic school, with Democritus, Heraclitus,
+Empedocles, Aristotle, Lucretius, and other ancient philosophers. The
+first imperfect attempts which they made astonish us, in a measure,
+by the flashes of mental light in which they anticipate modern ideas.
+It must be remembered that classical antiquity had not that solid
+groundwork for scientific speculation which has been provided by the
+countless observations and experiments of modern scientists. During the
+Middle Ages--especially during the domination of the papacy--scientific
+work in this direction entirely ceased. The torture and the stake of
+the Inquisition insured that an unconditional belief in the Hebrew
+mythology should be the final answer to all the questions of creation.
+Even the phenomena which led directly to the observation of the _facts_
+of evolution--the embryology of the plant and the animal, and of
+man--remained unnoticed, or only excited the interest of an occasional
+keen observer; but their discoveries were ignored or forgotten.
+Moreover, the path to a correct knowledge of natural development was
+barred by the dominant theory of preformation, the dogma which held
+that the characteristic form and structure of each animal and plant
+were already sketched in miniature in the germ (cf. p. 54).
+
+The science which we now call the science of evolution (in the broadest
+sense) is, both in its general outline and in its separate parts,
+a child of the nineteenth century; it is one of its most momentous
+and most brilliant achievements. Almost unknown in the preceding
+century, this theory has now become the sure foundation of our whole
+world-system. I have treated it exhaustively in my _General Morphology_
+(1866), more popularly in my _Natural History of Creation_ (1868), and
+in its special application to man in my _Anthropogeny_ (1874). Here I
+shall restrict myself to a brief survey of the chief advances which
+the science has made in the course of the century. It falls into four
+sections, according to the nature of its object; that is, it deals with
+the natural origin of (1) the cosmos, (2) the earth, (3) terrestrial
+forms of life, and (4) man.
+
+
+I.--MONISTIC COSMOGONY
+
+The first attempt to explain the constitution and the mechanical
+origin of the world in a simple manner by "Newtonian laws"--that is,
+by mathematical and physical laws--was made by Immanuel Kant in the
+famous work of his youth (1755), _General History of the Earth and
+Theory of the Heavens_. Unfortunately, this distinguished and daring
+work remained almost unknown for ninety years; it was only disinterred
+in 1845 by Alexander Humboldt in the first volume of his _Cosmos_. In
+the mean time the great French mathematician, Pierre Laplace, had
+arrived independently at similar views to those of Kant, and he gave
+them a mathematical foundation in his _Exposition du Système du Monde_
+(1796). His chief work, the _Mécanique Céleste_, appeared a hundred
+years ago. The analogous features of the cosmogony of Kant and Laplace
+consist, as is well known, in a mechanical explanation of the movements
+of the planets, and the conclusion which is drawn therefrom, that all
+the cosmic bodies were formed originally by a condensation of rotating
+nebulous spheres. This "nebular hypothesis" has been much improved
+and supplemented since, but it is still the best of all the attempts
+to explain the origin of the world on monistic and mechanical lines.
+It has recently been strongly confirmed and enlarged by the theory
+that this cosmogonic process did not simply take place once, but is
+periodically repeated. While new cosmic bodies arise and develop out
+of rotating masses of nebula in some parts of the universe, in other
+parts old, extinct, frigid suns come into collision, and are once more
+reduced by the heat generated to the condition of nebulæ.
+
+Nearly all the older and the more recent cosmogonies, including most
+of those which were inspired by Kant and Laplace, started from the
+popular idea that the world had had a beginning. Hence, according to
+a widespread version of the nebular hypothesis, "in the beginning"
+was made a vast nebula of infinitely attenuated and light material,
+and at a certain moment ("countless ages ago") a movement of rotation
+was imparted to this mass. Given this "first beginning" of the
+cosmogonic movement, it is easy, on mechanical principles, to deduce
+and mathematically establish the further phenomena of the formation of
+the cosmic bodies, the separation of the planets, and so forth. This
+first "origin of movement" is Du Bois-Reymond's second "world-enigma";
+he regards it as transcendental. Many other scientists and philosophers
+are equally helpless before this difficulty; they resign themselves to
+the notion that we have here a primary "supernatural impetus" to the
+scheme of things, a "miracle."
+
+In our opinion, this second "world-enigma" is solved by the recognition
+that movement is as innate and original a property of substance as
+is sensation. The proof of this monistic assumption is found, first,
+in the law of substance, and, secondly, in the discoveries which
+astronomy and physics have made in the latter half of the century. By
+the spectral analysis of Bunsen and Kirchhoff (1860) we have found, not
+only that the millions of bodies, which fill the infinity of space, are
+of the same material as our own sun and earth, but also that they are
+in various stages of evolution; we have obtained by its aid information
+as to the movements and distances of the stars, which the telescope
+would never have given us. Moreover, the telescope itself has been
+vastly improved, and has, in alliance with photography, made a host
+of scientific discoveries of which no one dreamed at the beginning
+of the century. In particular, a closer acquaintance with comets,
+meteorites, star-clusters, and nebulæ has helped us to realize the
+great significance of the smaller bodies which are found in millions in
+the space between the stars.
+
+We now know that the _paths_ of the millions of heavenly bodies are
+_changeable_, and to some extent irregular, whereas the planetary
+system was formerly thought to be constant, and the rotating spheres
+were described as pursuing their orbits in eternal regularity.
+Astro-physics owes much of its triumph to the immense progress of other
+branches of physics, of optics, and electricity, and especially of
+the theory of ether. And here, again, our supreme law of substance is
+found to be one of the most valuable achievements of modern science.
+We now know that it rules unconditionally in the most distant reaches
+of space, just as it does in our planetary system, in the most minute
+particle of the earth as well as in the smallest cell of our human
+frame. We are, moreover, justified in concluding, if we are not
+logically compelled to conclude, that the persistence of matter and
+force has held good throughout all time as it does to-day. Through all
+eternity the infinite universe has been, and is, subject to the law of
+substance.
+
+From this great progress of astronomy and physics, which mutually
+elucidate and supplement each other, we draw a series of most important
+conclusions with regard to the constitution and evolution of the
+cosmos, and the persistence and transformation of substance. Let us put
+them briefly in the following theses:
+
+I. The _extent_ of the universe is infinite and unbounded; it is empty
+in no part, but everywhere filled with substance.
+
+II. The _duration_ of the world is equally infinite and unbounded; it
+has no beginning and no end: it is eternity.
+
+III. Substance is everywhere and always in uninterrupted movement and
+transformation: nowhere is there perfect repose and rigidity; yet the
+infinite quantity of matter and of eternally changing force remains
+constant.
+
+IV. This universal movement of substance in space takes the form of an
+eternal cycle or of a periodical process of evolution.
+
+V. The phases of this evolution consist in a periodic change of
+consistency, of which the first outcome is the primary division into
+mass and ether--the ergonomy of ponderable and imponderable matter.
+
+VI. This division is effected by a progressive condensation of matter
+as the formation of countless infinitesimal "centres of condensation,"
+in which the inherent primitive properties of substance--feeling and
+inclination--are the active causes.
+
+VII. While minute and then larger bodies are being formed by this
+pyknotic process in one part of space, and the intermediate ether
+increases its strain, the opposite process--the destruction of cosmic
+bodies by collision--is taking place in another quarter.
+
+VIII. The immense quantity of heat which is generated in this
+mechanical process of the collision of swiftly moving bodies represents
+the new kinetic energy which effects the movement of the resultant
+nebulæ and the construction of new rotating bodies. The eternal drama
+begins afresh. Even our mother earth, which was formed of part of the
+gyrating solar system millions of ages ago, will grow cold and lifeless
+after the lapse of further millions, and, gradually narrowing its
+orbit, will fall eventually into the sun.
+
+It seems to me that these modern discoveries as to the periodic decay
+and re-birth of cosmic bodies, which we owe to the most recent advance
+of physics and astronomy, associated with the law of substance, are
+especially important in giving us a clear insight into the universal
+cosmic process of evolution. In their light our earth shrinks into the
+slender proportions of a "mote in the sunbeam," of which unnumbered
+millions chase each other through the vast depths of space. Our own
+"human nature," which exalted itself into an image of God in its
+anthropistic illusion, sinks to the level of a placental mammal, which
+has no more value for the universe at large than the ant, the fly of
+a summer's day, the microscopic infusorium, or the smallest bacillus.
+Humanity is but a transitory phase of the evolution of an eternal
+substance, a particular phenomenal form of matter and energy, the true
+proportion of which we soon perceive when we set it on the background
+of infinite space and eternal time.
+
+Since Kant explained space and time to be merely "forms of
+perception"--space the form of external, time of internal,
+sensitivity--there has been a keen controversy, which still continues,
+over this important problem. A large section of modern metaphysicians
+have persuaded themselves that this "critical fact" possesses a great
+importance as the starting-point of "a purely idealist theory of
+knowledge," and that, consequently, the natural opinion of the ordinary
+healthy mind as to the _reality_ of time and space is swept aside. This
+narrow and ultra-idealist conception of time and space has become a
+prolific source of error. It overlooks the fact that Kant only touched
+one side of the problem, the _subjective_ side, in that theory, and
+recognized the equal validity of its _objective_ side. "Time and
+space," he said, "have empirical reality, but transcendental ideality."
+Our modern monism is quite compatible with this thesis of Kant's,
+but not with the one-sided exaggeration of the subjective aspect of
+the problem; the latter leads logically to the absurd idealism that
+culminates in Berkeley's thesis, "Bodies are but ideas; their essence
+is in their perception." The thesis should be read thus: "Bodies are
+only ideas for my personal consciousness; their existence is just
+as real as that of my organs of thought, the ganglionic cells in
+the gray bed of my brain, which receive the impress of bodies on my
+sense-organs and form those ideas by association of the impressions." It
+is just as easy to doubt or to deny the reality of my own consciousness
+as to doubt that of time and space. In the delirium of fever, in
+hallucinations, in dreams, and in double-consciousness, I take ideas
+to be true which are merely fancies. I mistake my own personality for
+another (_vide_ p. 185); Descartes' famous _Cogito ergo sum_ applies no
+longer. On the other hand, the reality of time and space is now fully
+established by that expansion of our philosophy which we owe to the
+law of substance and to our monistic cosmogony. When we have happily
+got rid of the untenable idea of "empty space," there remains as the
+infinite "space-filling"-medium matter, in its two forms of ether and
+mass. So also we find a "time-filling" event in the eternal movement,
+or genetic energy, which reveals itself in the uninterrupted evolution
+of substance, in the _perpetuum mobile_ of the universe.
+
+As a body which has been set in motion continues to move as long as no
+external agency interferes with it, the idea was conceived long ago of
+constructing an apparatus which should illustrate perpetual motion. The
+fact was overlooked that every movement meets with external impediments
+and gradually ceases, unless a new impetus is given to it from without
+and a new force is introduced to counteract the impediments. Thus, for
+instance, a pendulum would swing backward and forward for an eternity
+at the same speed if the resistance of the atmosphere and the friction
+at the point it hangs from did not gradually deprive it of the
+mechanical kinetic energy of its motion and convert it into heat. We
+have to furnish it with fresh mechanical energy by a spring (or, as in
+the pendulum-clock, by the drag of a weight). Hence it is impossible to
+construct a machine that would produce, without external aid, a surplus
+of energy by which it could keep itself going. Every attempt to make
+such a _perpetuum mobile_ must necessarily fail; the discovery of the
+law of substance showed, in addition, the theoretical impossibility of
+it.
+
+The case is different, however, when we turn to the world at large, the
+boundless universe that is in eternal movement. The infinite matter,
+which fills it objectively, is what we call _space_ in our subjective
+impression of it; _time_ is our subjective conception of its eternal
+movement, which is, objectively, a periodic, cyclic evolution. These
+two "forms of perception" teach us the infinity and eternity of the
+universe. That is, moreover, equal to saying that the universe itself
+is a _perpetuum mobile_. This infinite and eternal "machine of the
+universe" sustains itself in eternal and uninterrupted movement,
+because every impediment is compensated by an "equivalence of energy,"
+and the unlimited sum of kinetic and potential energy remains always
+the same. The law of the persistence of force proves also that the idea
+of a _perpetuum mobile_ is just as applicable to, and as significant
+for, the cosmos as a whole as it is impossible for the isolated action
+of any part of it. Hence the theory of _entropy_ is likewise untenable.
+
+The able founder of the mechanical theory of heat (1850), Clausius,
+embodied the momentous contents of this important theory in two theses.
+The first runs: "The energy of the universe is constant"--that is
+one-half of our law of substance, the principle of energy (_vide_ p.
+230). The second thesis is: "The energy of the universe tends towards
+a maximum." In my opinion this second assertion is just as erroneous
+as the first is true. In the theory of Clausius the entire energy of
+the universe is of two kinds, one of which (heat of the higher degree,
+mechanical, electrical, chemical energy, etc.) is partly convertible
+into work, but the other is not; the latter energy, already converted
+into heat and distributed in the cooler masses, is irrevocably lost as
+far as any further work is concerned. Clausius calls this unconsumed
+energy, which is no longer available for mechanical work, _entropy_
+(that is, force that is directed _inward_); it is continually
+increasing at the cost of the other half. As, therefore, the mechanical
+energy of the universe is daily being transformed into heat, and this
+cannot be reconverted into mechanical force, the sum of heat and energy
+in the universe must continually tend to be reduced and dissipated. All
+difference of temperature must ultimately disappear, and the completely
+latent heat must be equally distributed through one inert mass of
+motionless matter. All organic life and movement must cease when this
+maximum of _entropy_ has been reached. That would be a real "end of the
+world."
+
+If this theory of entropy were true, we should have a "beginning"
+corresponding to this assumed "end" of the world--a minimum of
+entropy, in which the differences in temperature of the various parts
+of the cosmos would be at a maximum. Both ideas are quite untenable
+in the light of our monistic and consistent theory of the eternal
+cosmogenetic process; both contradict the law of substance. There is
+neither beginning nor end of the world. The universe is infinite, and
+eternally in motion; the conversion of kinetic into potential energy,
+and _vicissim_, goes on uninterruptedly; and the sum of this actual and
+potential energy remains constant. The second thesis of the mechanical
+theory of heat contradicts the first, and so must be rejected.
+
+The representatives of the theory of entropy are quite correct as long
+as they confine themselves to distinct processes, in which, _under
+certain conditions_, the latent heat cannot be reconverted into work.
+Thus, for instance, in the steam-engine the heat can only be converted
+into mechanical work when it passes from a warmer body (steam) into a
+cooler (water); the process cannot be reversed. In the world at large,
+however, quite other conditions obtain--conditions which permit the
+reconversion of latent heat into mechanical work. For instance, in the
+collision of two heavenly bodies, which rush towards each other at
+inconceivable speed, enormous quantities of heat are liberated, while
+the pulverized masses are hurled and scattered about space. The eternal
+drama begins afresh--the rotating mass, the condensation of its parts,
+the formation of new meteorites, their combination into larger bodies,
+and so on.
+
+
+II.--MONISTIC GEOGENY
+
+The history of the earth, of which we are now going to make a brief
+survey, is only a minute section of the history of the cosmos. Like
+the latter, it has been the object of philosophic speculation and
+mythological fantasy for many thousand years. Its true scientific
+study, however, is much younger; it belongs, for the most part, to
+the nineteenth century. The fact that the earth is a planet revolving
+round the sun was determined by the system of Copernicus (1543);
+Galilei, Kepler, and other great astronomers, mathematically determined
+its distance from the sun, the laws of its motion, and so forth.
+Kant and Laplace indicated, in their cosmogony, the way in which the
+earth had been developed from the parent sun. But the later history
+of the earth, the formation of its crust, the origin of its seas and
+continents, its mountains and deserts, was rarely made the subject
+of serious scientific research in the eighteenth century, and in the
+first two decades of the nineteenth. As a rule, men were satisfied with
+unreliable conjectures or with the traditional story of creation; once
+more the Mosaic legend barred the way to an independent investigation.
+
+In 1822 an important work appeared, which followed the same method
+in the scientific investigation of the history of the earth that
+had already proved the most fertile--the _ontological_ method, or
+the principle of "actualism." It consists in a careful study and
+manipulation of _actual_ phenomena with a view to the elucidation of
+the analogous historical processes of the past. The Society of Science
+at Göttingen had offered a prize in 1818 for "the most searching and
+comprehensive inquiry into the changes in the earth's crust which are
+historically demonstrable, and the application which may be made of a
+knowledge of them in the investigation of the terrestrial revolutions
+which lie beyond the range of history." This prize was obtained by Karl
+Hoff, of Gotha, for his distinguished work, _History of the Natural
+Changes in the Crust of the Earth in the Light of Tradition_ (1822-34).
+Sir Charles Lyell then applied this _ontological_ or _actualistic_
+method with great success to the whole province of geology; his
+_Principles of Geology_ (1830) laid the firm foundation on which
+the fabric of the history of the earth was so happily erected. The
+important geogenetic research of Alexander Humboldt, Leopold Buch,
+Gustav Bischof, Edward Süss, and other geologists, were wholly based
+on the empirical foundation and the speculative principles of Karl
+Hoff and Charles Lyell. They cleared the way for purely rational
+science in the field of geology; they removed the obstacles that had
+been put in the path by mythological fancy and religious tradition,
+especially by the Bible and its legends. I have already discussed the
+merits of Lyell, and his relations with his friend Charles Darwin,
+in the sixteenth and seventeenth chapters of my _Natural History of
+Creation_, and must refer the reader to the standard works on geology
+for a further acquaintance with the history of the earth and the great
+progress which dynamical and historical geology have made during the
+century.
+
+The first division of the history of the earth must be a separation
+of inorganic and organic geogeny; the latter begins with the first
+appearance of living things on our planet. The earlier section, the
+inorganic history of the earth, ran much the same course as that of the
+other planets of our system. They were all cast off as rings of nebula
+at the equator of the rotating solar mass, and gradually condensed
+into independent bodies. After cooling down a little, the glowing ball
+of the earth was formed out of the gaseous mass, and eventually, as
+the heat continued to radiate out into space, there was formed at its
+surface the thin solid crust on which we live. When the temperature at
+the surface had gone down to a certain point, the water descended upon
+it from the environing clouds of steam, and thus the first condition
+was secured for the rise of organic life. Many million years--certainly
+more than a hundred--have passed since this important process of
+the formation of water took place, introducing the third section of
+cosmogony, which we call _biogeny_.
+
+
+III.--MONISTIC BIOGENY
+
+The third phase of the evolution of the world opens with the advent of
+organisms on our planet, and continues uninterrupted from that point
+until the present day. The great problems which this most interesting
+part of the earth's history suggests to us were still thought insoluble
+at the beginning of the nineteenth century, or, at least, so difficult
+that their solution seemed to be extremely remote. Now, at the close of
+the century, we can affirm with legitimate pride that they have been
+substantially solved by modern biology and its theory of transformism;
+indeed, many of the phenomena of the organic world are now interpreted
+on physical principles as completely as the familiar physical phenomena
+of inorganic nature. The merit of making the first important step
+in this difficult path and of pointing out the way to the monistic
+solution of all the problems of biology must be accorded to the great
+French scientist, Jean Lamarck; it was in 1809, the year of the
+birth of Charles Darwin, that he published his famous _Philosophie
+Zoologique_. In this original work not only is a splendid effort made
+to interpret all the phenomena of organic life from a monistic and
+physical point of view, but the path is opened which alone leads to
+the solution of the greatest enigma of this branch of science--the
+problem of the natural origin of organic species. Lamarck, who had an
+equally extensive empirical acquaintance with zoology and botany, drew
+the first sketch of the theory of descent; he showed that all the
+countless members of the plant and animal kingdoms have arisen by slow
+transformation from simple, common ancestral types, and that it is the
+gradual modification of forms by _adaptation_, in reciprocal action
+with _heredity_, which has brought about this secular metamorphosis.
+
+I have fully appreciated the merit of Lamarck in the fifth chapter, and
+of Darwin in the sixth and seventh chapters, of the _Natural History
+of Creation_. Darwin, fifty years afterwards, not only gave a solid
+foundation to all the essential parts of the theory of descent, but he
+filled up the _lacunae_ of Lamarck's work by his theory of selection.
+Darwin reaped abundantly the success that Lamarck had never seen,
+with all his merit. His epoch-making work on _The Origin of Species
+by Natural Selection_ has transformed modern biology from its very
+foundations, in the course of the last forty years, and has raised it
+to a stage of development that yields to no other science in existence.
+Darwin is _the Copernicus of the organic world_, as I said in 1868, and
+E. du Bois-Reymond repeated fifteen years afterwards.[27]
+
+
+IV.--MONISTIC ANTHROPOGENY
+
+The fourth and last phase of the world's history must be for us men
+that latest period of time which has witnessed the development of our
+own race. Lamarck (1809) had already recognized that this evolution is
+only rationally conceivable as the outcome of a natural process, by
+"descent from the apes," our next of kin among the mammals. Huxley then
+proved, in his famous essay on _The Place of Man in Nature_, that this
+momentous thesis is an inevitable consequence of the theory of descent,
+and is thoroughly established by the facts of anatomy, embryology, and
+palæontology. He considered this "question of all questions" to be
+substantially answered. Darwin followed with a brilliant discussion
+of the question under many aspects in his _Descent of Man_ (1871).
+I had myself devoted a special chapter to this important problem of
+the science of evolution in my _General Morphology_ (1866). In 1874 I
+published my _Anthropogeny_, which contains the first attempt to trace
+the descent of man through the entire chain of his ancestry right up to
+the earliest archigonous monera; the attempt was based equally on the
+three great "documents" of evolutionary science--anatomy, embryology,
+and palæontology. The progress we have made in anthropogenetic research
+during the last few years is described in the paper which I read on
+"Our Present Knowledge of the Origin of Man" at the International
+Congress of Zoologists at Cambridge in 1898.[28]
+
+
+
+
+CHAPTER XIV
+
+THE UNITY OF NATURE
+
+    The Monism of the Cosmos--Essential Unity of Organic
+    and Inorganic Nature--Carbon-Theory--The Hypothesis of
+    Abiogenesis--Mechanical and Purposive Causes--Mechanicism and
+    Teleology in Kant's Works--Design in the Organic and Inorganic
+    Worlds--Vitalism--Neovitalism--Dysteleology (the Moral of the
+    Rudimentary Organs)--Absence of Design in, and Imperfection of,
+    Nature--Telic Action in Organized Bodies--Its Absence in Ontogeny
+    and Phylogeny--The Platonist "Ideas"--No Moral Order Discoverable
+    in the History of the Organic World, of the Vertebrates, or of the
+    Human Race--Prevision--Design and Chance
+
+
+One of the first things to be proved by the law of substance is the
+basic fact that any natural force can be directly or indirectly
+converted into any other. Mechanical and chemical energy, sound and
+heat, light and electricity, are mutually convertible; they seem to be
+but different modes of one and the same fundamental force or _energy_.
+Thence follows the important thesis of the unity of all natural
+forces, or, as it may also be expressed, the "monism of energy."
+This fundamental principle is now generally recognized in the entire
+province of physics and chemistry, as far as it applies to inorganic
+substances.
+
+It seems to be otherwise with the organic world and its wealth of
+color and form. It is, of course, obvious that a great part of the
+phenomena of life may be immediately traced to mechanical and chemical
+energy, and to the effects of electricity and light. For other vital
+processes, however, especially for psychic activity and consciousness,
+such an interpretation is vigorously contested. Yet the modern science
+of evolution has achieved the task of constructing a bridge between
+these two apparently irreconcilable provinces. We are now certain that
+all the phenomena of organic life are subject to the universal law of
+substance no less than the phenomena of the inorganic universe.
+
+The unity of nature which necessarily follows, and the demolition of
+the earlier dualism, are certainly among the most valuable results of
+modern evolution. Thirty-three years ago I made an exhaustive effort
+to establish this "monism of the cosmos" and the essential unity of
+organic and inorganic nature by a thorough, critical demonstration,
+and a comparison of the accordance of these two great divisions of
+nature with regard to matter, form, and force.[29] A short epitome of
+the result is given in the fifteenth chapter of my _Natural History
+of Creation_. The views I put forward are accepted by the majority
+of modern scientists, but an attempt has been made in many quarters
+lately to dispute them and to maintain the old antithesis of the two
+divisions of nature. The ablest of these is to be found in the recent
+_Welt als That_ of the botanist Reinke. It defends _pure cosmological_
+dualism with admirable lucidity and consistency, and only goes to prove
+how utterly untenable the teleological system is that is connected
+therewith. According to the author, physical and chemical forces alone
+are at work in the entire field of inorganic nature, while in the
+organic world we find "intelligent forces," regulative or dominant
+forces. The law of substance is supposed to apply to the one, but not
+to the other. On the whole, it is a question of the old antithesis of
+a mechanical and a teleological system. But before we go more fully
+into it, let us glance briefly at two other theories, which seem to
+me to be of great importance in the decision of that controversy--the
+carbon-theory and the theory of spontaneous generation.
+
+Physiological chemistry has, after countless analyses, established the
+following five facts during the last forty years:
+
+I. No other elements are found in organic bodies than those of the
+inorganic world.
+
+II. The combinations of elements which are peculiar to organisms,
+and which are responsible for their vital phenomena, are compound
+protoplasmic substances, of the group of albuminates.
+
+III. Organic life itself is a chemico-physical process, based on the
+metabolism (or interchange of material) of these albuminates.
+
+IV. The only element which is capable of building up these compound
+albuminates, in combination with other elements (oxygen, hydrogen,
+nitrogen, and sulphur), is carbon.
+
+V. These protoplasmic compounds of carbon are distinguished from
+most other chemical combinations by their very intricate molecular
+structure, their instability, and their jelly-like consistency.
+
+On the basis of these five fundamental facts the following
+"carbon-theory" was erected thirty-three years ago: "The peculiar
+chemico-physical properties of carbon--especially the fluidity and
+the facility of decomposition of the most elaborate albuminoid
+compounds of carbon--are the sole and the mechanical causes of
+the specific phenomena of movement, which distinguish organic from
+inorganic substances, and which are called life, in the usual sense
+of the word" (see _The Natural History of Creation_). Although this
+"carbon-theory" is warmly disputed in some quarters, no better monistic
+theory has yet appeared to replace it. We have now a much better and
+more thorough knowledge of the physiological relations of cell-life,
+and of the chemistry and physics of the living protoplasm, than we had
+thirty-three years ago, and so it is possible to make a more confident
+and effective defence of the carbon-theory.
+
+The old idea of spontaneous generation is now taken in many different
+senses. It is owing to this indistinctness of the idea, and its
+application to so many different hypotheses, that the problem is one
+of the most contentious and confused of the science of the day. I
+restrict the idea of spontaneous generation--also called abiogenesis
+or archigony--to the first development of living protoplasm out of
+inorganic carbonates, and distinguish two phases in this "beginning
+of biogenesis": (1) _autogony_, or the rise of the simplest
+protoplasmic substances in a formative fluid, and (2) _plasmogony_,
+the differentiation of individual primitive organisms out of these
+protoplasmic compounds, in the form of _monera_. I have treated this
+important, though difficult, problem so exhaustively in the fifteenth
+chapter of my _Natural History of Creation_ that I may content myself
+here with referring to it. There is also a very searching and severely
+scientific inquiry into it in my _General Morphology_ (1866). Naegeli
+has also treated the hypothesis in quite the same sense in his
+mechanico-physiological theory of descent (1884), and has represented
+it to be an indispensable thesis in any natural theory of evolution.
+I entirely agree with his assertion that "to reject abiogenesis is to
+admit a miracle."
+
+The hypothesis of spontaneous generation and the allied carbon-theory
+are of great importance in deciding the long-standing conflict between
+the _teleological_ (dualistic) and the _mechanical_ (monistic)
+interpretation of phenomena. Since Darwin gave us the key to the
+monistic explanation of organization in his theory of selection forty
+years ago, it has become possible for us to trace the splendid variety
+of orderly tendencies of the organic world to mechanical, natural
+causes, just as we could formerly in the inorganic world alone. Hence
+the supernatural and telic forces, to which the scientist had had
+recourse, have been rendered superfluous. Modern metaphysics, however,
+continues to regard the latter as indispensable and the former as
+inadequate.
+
+No philosopher has done more than Immanuel Kant in defining the
+profound distinction between efficient and final causes, with relation
+to the interpretation of the whole cosmos. In his well-known earlier
+work on _The General Natural History and Theory of the Heavens_ he
+made a bold attempt "to treat the constitution and the mechanical
+origin of the entire fabric of the universe according to Newtonian
+laws." This "cosmological nebular theory" was based entirely on the
+mechanical phenomena of gravitation. It was expanded and mathematically
+established later on by Laplace. When the famous French astronomer
+was asked by Napoleon I. where God, the creator and sustainer of all
+things, came in in his system, he clearly and honestly replied: "Sire,
+I have managed without that hypothesis." That indicated the atheistic
+character which this mechanical cosmogony shares with all the other
+inorganic sciences. This is the more noteworthy because the theory of
+Kant and Laplace is now almost universally accepted; every attempt to
+supersede it has failed. When atheism is denounced as a grave reproach,
+as it so often is, it is well to remember that the reproach extends to
+the whole of modern science, in so far as it gives a purely mechanical
+interpretation of the inorganic world.
+
+Mechanicism (in the Kantian sense) alone can give us a true explanation
+of natural phenomena, for it traces them to their real efficient
+causes, to blind and unconscious agencies, which are determined in
+their action only by the material constitution of the bodies we are
+investigating. Kant himself emphatically affirms that "there can be
+no science without this mechanicism of nature," and that the capacity
+of human reason to give a mechanical interpretation of phenomena is
+unlimited. But when he came subsequently to give an elucidation of
+the complex phenomena of organic nature in his _critique_ of the
+teleological system, he declared that these mechanical causes were
+inadequate; that in this we must call _final causes_ to our assistance.
+It is true, he said, that even here we must recognize the theoretical
+faculty of the mind to give a mechanical interpretation, but its actual
+competence to do so is restricted. He grants it this capacity to some
+extent; but for the majority of the vital processes (and especially for
+man's psychic activity) he thinks we are bound to postulate _final_
+causes. The remarkable §79 of the _critique_ of judgment bears the
+characteristic heading: "On the Necessity for the Subordination of
+the Mechanical Principle to the Teleological in the Explanation of a
+Thing as a Natural End." It seemed to Kant so impossible to explain
+the orderly processes in the living organism without postulating
+supernatural final causes (that is, a purposive creative force) that
+he said: "It is quite certain that we cannot even satisfactorily
+understand, much less elucidate, the nature of an organism and its
+internal faculty on purely mechanical natural principles; it is so
+certain, indeed, that we may confidently say, 'It is absurd for a man
+to conceive the idea even that some day a Newton will arise who can
+explain the origin of a single blade of grass by natural laws which are
+uncontrolled by design'--such a hope is entirely forbidden us." Seventy
+years afterwards this impossible "Newton of the organic world" appeared
+in the person of Charles Darwin, and achieved the great task that Kant
+had deemed impracticable.
+
+Since Newton (1682) formulated the law of gravitation, and Kant (1755)
+established "the constitution and mechanical origin of the entire
+fabric of the world on Newtonian laws," and Laplace (1796) provided
+a mathematical foundation for this law of cosmic mechanicism, the
+whole of the inorganic sciences have become purely _mechanical_, and
+at the same time purely _atheistic_. Astronomy, cosmogony, geology,
+meteorology, and inorganic physics and chemistry are now absolutely
+ruled by mechanical laws on a mathematical foundation. The idea of
+"design" has wholly disappeared from this vast province of science.
+At the close of the nineteenth century, now that this monistic view
+has fought its way to general recognition, no scientist ever asks
+seriously of the "purpose" of any single phenomenon in the whole of
+this great field. Is any astronomer likely to inquire seriously to-day
+into the purpose of planetary motion, or a mineralogist to seek design
+in the structure of a crystal? Does the physicist investigate the
+purpose of electric force, or the chemist that of atomic weight? We
+may confidently answer in the negative--certainly not, in the sense
+that God, or a purposive natural force, had at some time created these
+fundamental laws of the mechanism of the universe with a definite
+design, and causes them to work daily in accordance with his rational
+will. The anthropomorphic notion of a deliberate architect and ruler of
+the world has gone forever from this field; the "eternal, iron laws of
+nature" have taken his place.
+
+But the idea of design has a very great significance and application
+in the _organic_ world. We do undeniably perceive a purpose in the
+structure and in the life of an organism. The plant and the animal
+seem to be controlled by a definite design in the combination of their
+several parts, just as clearly as we see in the machines which man
+invents and constructs; as long as life continues the functions of the
+several organs are directed to definite ends, just as is the operation
+of the various parts of a machine. Hence it was quite natural that the
+older naïve study of nature, in explaining the origin and activity
+of the living being, should postulate a creator who had "arranged
+all things with wisdom and understanding," and had constructed each
+plant and animal according to the special purpose of its life. The
+conception of this "almighty creator of heaven and earth" was usually
+quite anthropomorphic; he created "everything after its kind." As long
+as the creator seemed to man to be of human shape, to think with his
+brain, see with his eyes, and fashion with his hands, it was possible
+to form a definite picture of this "divine engineer" and his artistic
+work in the great workshop of creation. This was not so easy when
+the idea of God became refined, and man saw in his "invisible God" a
+creator without organs--a gaseous being. Still more unintelligible
+did these anthropomorphic ideas become when physiology substituted
+for the conscious, divine architect an unconscious, creative "vital
+force"--a mysterious, purposive, natural force, which differed from the
+familiar forces of physics and chemistry, and only took these in part,
+during life, into its service. This vitalism prevailed until about the
+middle of the nineteenth century. Johannes Müller, the great Berlin
+physiologist, was the first to menace it with a destructive dose of
+facts. It is true that the distinguished biologist had himself (like
+all others in the first half of the century) been educated in a belief
+in this vital force, and deemed it indispensable for an elucidation of
+the ultimate sources of life; nevertheless, in his classical and still
+unrivalled _Manual of Physiology_ (1833) he gave a demonstrative proof
+that there is really nothing to be said for this vital force. Müller
+himself, in a long series of remarkable observations and experiments,
+showed that most of the vital processes in the human organism (and in
+the other animals) take place according to physical and chemical laws,
+and that many of them are capable of mathematical determination. That
+was no less true of the animal functions of the muscles and nerves,
+and of both the higher and the lower sense-organs, than of the vegetal
+functions of digestion, assimilation, and circulation. Only two
+branches of the life of the organism, mental action and reproduction,
+retained any element of mystery, and seemed inexplicable without
+assuming a vital force. But immediately after Müller's death such
+important discoveries and advances were made in these two branches
+that the uneasy "phantom of vital force" was driven from its last
+refuge. By a very remarkable coincidence Johannes Müller died in the
+year 1858, which saw the publication of Darwin's first communication
+concerning his famous theory. The theory of selection solved the great
+problem that had mastered Müller--the question of the origin of orderly
+arrangements from purely mechanical causes.
+
+Darwin, as we have often said, had a twofold immortal merit in the
+field of philosophy--firstly, the reform of Lamarck's theory of
+descent, and its establishment on the mass of facts accumulated in the
+course of the half-century; secondly, the conception of the theory
+of selection, which first revealed to us the true causes of the
+gradual formation of species. Darwin was the first to point out that
+the "struggle for life" is the unconscious regulator which controls
+the reciprocal action of heredity and adaptation in the gradual
+transformation of species; it is the great "selective divinity" which,
+by a purely "natural choice," without preconceived design, creates
+new forms, just as selective man creates new types by an "artificial
+choice" with a definite design. That gave us the solution of the great
+philosophic problem: "How can purposive contrivances be produced by
+purely mechanical processes without design?" Kant held the problem to
+be insoluble, although Empedocles had pointed out the direction of the
+solution two thousand years before. His principle of "teleological
+mechanism" has become more and more accepted of late years, and
+has furnished a mechanical explanation even of the finest and most
+recondite processes of organic life by "the functional self-production
+of the purposive structure." Thus have we got rid of the transcendental
+"design" of the ideological philosophy of the schools, which was the
+greatest obstacle to the growth of a rational and monistic conception
+of nature.
+
+Very recently, however, this ancient phantom of a mystic vital force,
+which seemed to be effectually banished, has put in a fresh appearance;
+a number of distinguished biologists have attempted to reintroduce it
+under another name. The clearest presentation of it is to be found in
+the _Welt als That_, of the Kiel botanist, J. Reinke. He takes upon
+himself the defence of the notion of miracle, of theism, of the Mosaic
+story of creation, and of the constancy of species; he calls "vital
+forces," in opposition to physical forces, the directive or dominant
+forces. Other neovitalists prefer, in the good old anthropomorphic
+style, a "supreme" engineer, who has endowed organic substance with a
+purposive structure, directed to the realization of a definite plan.
+These curious teleological hypotheses, and the objections to Darwinism
+which generally accompany them, do not call for serious scientific
+refutation to-day.
+
+Thirty-three years ago I gave the title of "dysteleology" to the
+science of those extremely interesting and significant biological
+facts, which, in the most striking fashion, give a direct contradiction
+to the teleological idea "of the purposive arrangement of the living
+organism."[30] This "science of rudimentary, abortive, arrested,
+distorted, atrophied, and cataplastic individuals" is based on an
+immense quantity of remarkable phenomena, which were long familiar to
+zoologists and botanists, but were not properly interpreted, and their
+great philosophic significance appreciated, until Darwin.
+
+All the higher animals and plants, or, in general, all organisms which
+are not entirely simple in structure, but are made up of a number of
+organs in orderly co-operation, are found, on close examination, to
+possess a number of useless or inoperative members, sometimes, indeed,
+hurtful and dangerous. In the flowers of most plants we find, besides
+the actual sex-leaves that effect reproduction, a number of other
+leaf-organs which have no use or meaning (arrested or "miscarried"
+pistils, fruit, corona, and calix-leaves, etc.). In the two large and
+variegated classes of flying animals, birds and insects, there are,
+besides the forms which make constant use of their wings, a number of
+species which have undeveloped wings and cannot fly. In nearly every
+class of the higher animals which have eyes there are certain types
+that live in the dark; they have eyes, as a rule, but undeveloped and
+useless for vision. In our own human organism we have similar useless
+rudimentary structures in the muscles of the ear, in the eye-lid, in
+the nipple and milk-gland of the male, and in other parts of the body;
+indeed, the vermiform appendix of our cæcum is not only useless, but
+extremely dangerous, and inflammation of it is responsible for a number
+of deaths every year.
+
+Neither the old mystic vitalism nor the new, equally irrational,
+neovitalism can give any explanation of these and many other
+purposeless contrivances in the structure of the plant and the animal;
+but they are very simple in the light of the theory of descent. It
+shows that these rudimentary organs are atrophied, owing to disuse.
+Just as our muscles, nerves, and organs of sense are strengthened by
+exercise and frequent use, so, on the other hand, they are liable to
+degenerate more or less by disuse or suspended exercise. But, although
+the development of the organs is promoted by exercise and adaptation,
+they by no means disappear without leaving a trace after neglect; the
+force of heredity retains them for many generations, and only permits
+their gradual disappearance after the lapse of a considerable time.
+The blind "struggle for existence between the organs" determines their
+historical disappearance, just as it effected their first origin and
+development. There is no internal "purpose" whatever in the drama.
+
+The life of the animal and the plant bears the same universal character
+of incompleteness as the life of man. This is directly attributable
+to the circumstance that nature--organic as well as inorganic--is
+in a perennial state of evolution, change, and transformation. This
+evolution seems on the whole--at least as far as we can survey the
+development of organic life on our planet--to be a progressive
+improvement, an historical advance from the simple to the complex,
+the lower to the higher, the imperfect to the perfect. I have proved
+in my _General Morphology_ that this historical progress--or gradual
+perfecting (_teleosis_)--is the inevitable result of selection, and not
+the outcome of a preconceived design. That is clear from the fact that
+no organism is perfect; even if it does perfectly adapt itself to its
+environment at a given moment, this condition would not last very long;
+the conditions of existence of the environment are themselves subject
+to perpetual change and they thus necessitate a continuous adaptation
+on the part of the organism.
+
+Under the title of _Design in the Living Organism_, the famous
+embryologist, Karl Ernst Baer, published a work in 1876 which, together
+with the article on Darwinism which accompanied it, proved very
+acceptable to our opponents, and is still much quoted in opposition
+to evolution. It was a revival of the old teleological system under
+a new name, and we must devote a line of criticism to it. We must
+premise that, though Baer was a scientist of the highest order, his
+original monistic views were gradually marred by a tinge of mysticism
+with the advance of age, and he eventually became a thorough dualist.
+In his profound work on "the evolution of animals" (1828), which he
+himself entitled _Observation and Experiment_, these two methods of
+investigation are equally applied. By careful observation of the
+various phenomena of the development of the animal ovum Baer succeeded
+in giving the first consistent presentation of the remarkable changes
+which take place in the growth of the vertebrate from a simple
+egg-cell. At the same time he endeavored, by far-seeing comparison
+and keen reflection, to learn the causes of the transformation, and
+to reduce them to general constructive laws. He expressed the general
+result of his research in the following thesis: "The evolution of
+the individual is the story of the growth of individuality in every
+respect." He meant that "the one great thought that controls all the
+different aspects of animal evolution is the same that gathered the
+scattered fragments of space into spheres and linked them into solar
+systems. This thought is no other than life itself, and the words and
+syllables in which it finds utterance are the varied forms of living
+things."
+
+Baer, however, did not attain to a deeper knowledge of this great
+genetic truth and a clearer insight into the real efficient causes of
+organic evolution, because his attention was exclusively given to
+one half of evolutionary science, the science of the evolution of the
+individual, embryology, or, in a wider sense, _ontogeny_. The other
+half, the science of the evolution of species, _phylogeny_, was not yet
+in existence, although Lamarck had already pointed out the way to it in
+1809. When it was established by Darwin in 1859, the aged Baer was no
+longer in a position to appreciate it; the fruitless struggle which he
+led against the theory of selection clearly proved that he understood
+neither its real meaning nor its philosophic importance. Teleological
+and, subsequently, theological speculations had incapacitated the
+ageing scientist from appreciating this greatest reform of biology. The
+teleological observations which he published against it in his _Species
+and Studies_ in his eighty-fourth year are mere repetitions of errors
+which the teleology of the dualists has opposed to the mechanical or
+monistic system for more than two thousand years. The "telic idea"
+which, according to Baer, controls the entire evolution of the animal
+from the ovum, is only another expression for the eternal "idea" of
+Plato and the _entelecheia_ of his pupil Aristotle.
+
+Our modern biogeny gives a purely physiological explanation of the
+facts of embryology, in assigning the functions of heredity and
+adaptation as their causes. The great biogenetic law, which Baer
+failed to appreciate, reveals the intimate causal connection between
+the _ontogenesis_ of the individual and the _phylogenesis_ of its
+ancestors; the former seems to be a recapitulation of the latter.
+Nowhere, however, in the evolution of animals and plants do we find any
+trace of design, but merely the inevitable outcome of the struggle for
+existence, the blind controller, instead of the provident God, that
+effects the changes of organic forms by a mutual action of the laws of
+heredity and adaptation. And there is no more trace of "design" in the
+embryology of the individual plant, animal, or man. This _ontogeny_
+is but a brief epitome of _phylogeny_, an abbreviated and condensed
+recapitulation of it, determined by the physiological laws of heredity.
+
+Baer ended the preface to his classical _Evolution of Animals_ (1828)
+with these words: "The palm will be awarded to the fortunate scientist
+who succeeds in reducing the constructive forces of the animal body
+to the general forces or life-processes of the entire world. The tree
+has not yet been planted which is to make his cradle." The great
+embryologist erred once more. That very year, 1828, witnessed the
+arrival of Charles Darwin at Cambridge University (for the purpose of
+studying theology!)--the "fortunate scientist" who richly earned the
+palm thirty years afterwards by his theory of selection.
+
+In the philosophy of history--that is, in the general reflections which
+historians make on the destinies of nations and the complicated course
+of political evolution--there still prevails the notion of a "moral
+order of the universe." Historians seek in the vivid drama of history
+a leading design, an ideal purpose, which has ordained one or other
+race or state to a special triumph, and to dominion over the others.
+This teleological view of history has recently become more strongly
+contrasted with our monistic view in proportion as monism has proved
+to be the only possible interpretation of inorganic nature. Throughout
+the whole of astronomy, geology, physics, and chemistry there is no
+question to-day of a "moral order," or a personal God, whose "hand hath
+disposed all things in wisdom and understanding." And the same must
+be said of the entire field of biology, the whole constitution and
+history of organic nature, if we set aside the question of man for the
+moment. Darwin has not only proved by his theory of selection that the
+orderly processes in the life and structure of animals and plants have
+arisen by mechanical laws without any preconceived design, but he has
+shown us in the "struggle for life" the powerful natural force which
+has exerted supreme control over the entire course of organic evolution
+for millions of years. It may be said that the struggle for life is the
+"survival of the fittest" or the "victory of the best"; that is only
+correct when we regard the strongest as the best (in a moral sense).
+Moreover, the whole history of the organic world goes to prove that,
+besides the predominant advance towards perfection, there are at all
+times cases of retrogression to lower stages. Even Baer's notion of
+"design" has no moral feature whatever.
+
+Do we find a different state of things in the history of peoples, which
+man, in his anthropocentric presumption, loves to call "the history of
+the world"? Do we find in every phase of it a lofty moral principle or
+a wise ruler, guiding the destinies of nations? There can be but one
+answer in the present advanced stage of natural and human history: No.
+The fate of those branches of the human family, those nations and races
+which have struggled for existence and progress for thousands of years,
+is determined by the same "eternal laws of iron" as the history of the
+whole organic world which has peopled the earth for millions of years.
+
+Geologists distinguish three great epochs in the organic history of
+the earth, as far as we can read it in the monuments of the science of
+fossils--the primary, secondary, and tertiary epochs. According to a
+recent calculation, the first occupied at least thirty-four million,
+the second eleven million, and the third three million years. The
+history of the family of vertebrates, from which our own race has
+sprung, unfolds clearly before our eyes during this long period. Three
+different stages in the evolution of the vertebrate correspond to the
+three epochs; the _fishes_ characterized the primary (palæozoic) age,
+the _reptiles_ the secondary (mesozoic), and the _mammals_ the tertiary
+(cænozoic). Of the three groups the fishes rank lowest in organization,
+the reptiles come next, and the mammals take the highest place. We
+find, on nearer examination of the history of the three classes, that
+their various orders and families also advanced progressively during
+the three epochs towards a higher stage of perfection. May we consider
+this progressive development as the outcome of a conscious design or
+a moral order of the universe? Certainly not. The theory of selection
+teaches us that this organic progress, like the earlier organic
+differentiation, is an inevitable consequence of the struggle for
+existence. Thousands of beautiful and remarkable species of animals and
+plants have perished during those forty-eight million years, to give
+place to stronger competitors, and the victors in this struggle for
+life were not always the noblest or most perfect forms in a moral sense.
+
+It has been just the same with the history of humanity. The splendid
+civilization of classical antiquity perished because Christianity,
+with its faith in a loving God and its hope of a better life beyond
+the grave, gave a fresh, strong impetus to the soaring human mind. The
+Papal Church quickly degenerated into a pitiful caricature of real
+Christianity, and ruthlessly scattered the treasures of knowledge
+which the Hellenic philosophy had gathered; it gained the dominion
+of the world through the ignorance of the credulous masses. In time
+the Reformation broke the chains of this mental slavery, and assisted
+reason to secure its right once more. But in the new, as in the
+older, period the great struggle for existence went on in its eternal
+fluctuation, with no trace of a moral order.
+
+And it is just as impossible for the impartial and critical observer
+to detect a "wise providence" in the fate of individual human beings
+as a moral order in the history of peoples. Both are determined with
+iron necessity by a mechanical causality which connects every single
+phenomenon with one or more antecedent causes. Even the ancient Greeks
+recognized _ananke_, the blind _heimarmene_, the fate "that rules
+gods and men," as the supreme principle of the universe. Christianity
+replaced it by a conscious Providence, which is not blind, but sees,
+and which governs the world in patriarchal fashion. The anthropomorphic
+character of this notion, generally closely connected with belief in
+a personal God, is quite obvious. Belief in a "loving Father," who
+unceasingly guides the destinies of one billion five hundred million
+men on our planet, and is attentive at all times to their millions of
+contradictory prayers and pious wishes, is absolutely impossible; that
+is at once perceived on laying aside the colored spectacles of "faith"
+and reflecting rationally on the subject.
+
+As a rule, this belief in Providence and the tutelage of a "loving
+Father" is more intense in the modern civilized man--just as in the
+uncultured savage--when some good fortune has fallen him: an escape
+from peril of life, recovery from a severe illness, the winning of the
+first prize in a lottery, the birth of a long-delayed child, and so
+forth. When, on the other hand, a misfortune is met with, or an ardent
+wish is not fulfilled, "Providence" is forgotten. The wise ruler of the
+world slumbered--or refused his blessing.
+
+In the extraordinary development of commerce of the nineteenth century
+the number of catastrophes and accidents has necessarily increased
+beyond all imagination; of that the journal is a daily witness.
+Thousands are killed every year by shipwreck, railway accidents, mine
+accidents, etc. Thousands slay each other every year in war, and the
+preparation for this wholesale massacre absorbs much the greater part
+of the revenue in the highest civilized nations, the chief professors
+of "Christian charity." And among these hundreds of thousands of annual
+victims of modern civilization strong, industrious, courageous workers
+predominate. Yet the talk of a "moral order" goes on.
+
+Since impartial study of the evolution of the world teaches us that
+there is no definite aim and no special purpose to be traced in it,
+there seems to be no alternative but to leave everything to "blind
+chance." This reproach has been made to the transformism of Lamarck and
+Darwin, as it had been to the previous systems of Kant and Laplace;
+there are a number of dualist philosophers who lay great stress on it.
+It is, therefore, worth while to make a brief remark upon it.
+
+One group of philosophers affirms, in accordance with its teleological
+conception, that the whole cosmos is an orderly system, in which every
+phenomenon has its aim and purpose; there is no such thing as chance.
+The other group, holding a mechanical theory, expresses itself thus:
+The development of the universe is a monistic mechanical process, in
+which we discover no aim or purpose whatever; what we call design in
+the organic world is a special result of biological agencies; neither
+in the evolution of the heavenly bodies nor in that of the crust of
+our earth do we find any trace of a controlling purpose--all is the
+result of chance. Each party is right--according to its definition of
+chance. The general law of causality, taken in conjunction with the law
+of substance, teaches us that every phenomenon has a mechanical cause;
+in this sense there is no such thing as chance. Yet it is not only
+lawful, but necessary, to retain the term for the purpose of expressing
+the simultaneous occurrence of two phenomena, which are not causally
+related to each other, but of which each has its own mechanical cause,
+independent of that of the other. Everybody knows that chance, in its
+monistic sense, plays an important part in the life of man and in the
+universe at large. That, however, does not prevent us from recognizing
+in each "chance" event, as we do in the evolution of the entire
+cosmos, the universal sovereignty of nature's supreme law, _the law of
+substance_.
+
+
+
+
+CHAPTER XV
+
+GOD AND THE WORLD
+
+    The Idea of God in General--Antithesis of God and the World; the
+    Supernatural and Nature--Theism and Pantheism--Chief Forms of
+    Theism--Polytheism--Triplotheism--Amphitheism--Monotheism--Religious
+    Statistics--Naturalistic Monotheism--Solarism--Anthropistic
+    Monotheism--The Three Great Mediterranean
+    Religions--Mosaism--Christianity--The Cult of the Madonna and
+    the Saints--Papal Polytheism--Islam--Mixotheism--Nature of
+    Theism--An Extra-mundane and Anthropomorphic God; a Gaseous
+    Vertebrate--Pantheism--Intramundane God (Nature)--The Hylozoism
+    of the Ionic Monists (Anaximander)--Conflict of Pantheism and
+    Christianity--Spinoza--Modern Monism--Atheism
+
+
+For thousands of years humanity has placed the last and supreme basis
+of all phenomena in an efficient cause, to which it gives the title of
+God (_deus_, _theos_). Like all general ideas, this notion of God has
+undergone a series of remarkable modifications and transformations in
+the course of the evolution of reason. Indeed, it may be said that no
+other idea has had so many metamorphoses; for no other belief affects
+in so high a degree the chief objects of the mind and of rational
+science, as well as the deepest interests of the emotion and poetic
+fancy of the believer.
+
+A comparative criticism of the many different forms of the idea of God
+would be extremely interesting and instructive; but we have not space
+for it in the present work. We must be content with a passing glance
+at the most important forms of the belief and their relation to the
+modern thought that has been evoked by a sound study of nature. For
+further information on this interesting question the reader would do
+well to consult the distinguished work of Adalbert Svoboda, _Forms of
+Faith_ (1897).
+
+When we pass over the finer shades and the variegated clothing of
+the God-idea and confine our attention to its chief element, we can
+distribute all the different presentations of it in two groups--the
+_theistic_ and _pantheistic_ group. The latter is closely connected
+with the monistic, or rational, view of things, and the former is
+associated with dualism and mysticism.
+
+
+I.--THEISM
+
+In this view God is distinct from, and opposed to, the world as its
+creator, sustainer, and ruler. He is always conceived in a more or
+less human form, as an organism which thinks and acts like a man--only
+on a much higher scale. This anthropomorphic God, polyphyletically
+evolved by the different races, assumes an infinity of shapes in their
+imagination, from fetichism to the refined monotheistic religions
+of the present day. The chief forms of theism are polytheism,
+triplotheism, amphitheism, and monotheism.
+
+The polytheist peoples the world with a variety of gods and goddesses,
+which enter into its machinery more or less independently. _Fetichism_
+sees such subordinate deities in the lifeless body of nature, in rocks,
+in water, in the air, in human productions of every kind (pictures,
+statues, etc.). _Demonism_ sees gods in living organisms of every
+species--trees, animals, and men. This kind of polytheism is found in
+innumerable forms even in the lowest tribes. It reaches the highest
+stage in Hellenic polytheism, in the myths of ancient Greece, which
+still furnish the finest images to the modern poet and artist. At a
+much lower stage we have Catholic polytheism, in which innumerable
+"saints" (many of them of very equivocal repute) are venerated as
+subordinate divinities, and prayed to to exert their mediation with the
+supreme divinity.
+
+The dogma of the "Trinity," which still comprises three of the chief
+articles of faith in the creed of Christian peoples, culminates in the
+notion that the one God of Christianity is really made up of _three_
+different persons: (1) God the Father, the omnipotent creator of heaven
+and earth (this untenable myth was refuted long ago by scientific
+cosmogony, astronomy, and geology); (2) Jesus Christ; and (3) the Holy
+Ghost, a mystical being, over whose incomprehensible relation to the
+Father and the Son millions of Christian theologians have racked their
+brains in vain for the last nineteen hundred years. The Gospels, which
+are the only clear sources of this _triplotheism_, are very obscure as
+to the relation of these three persons to each other, and do not give a
+satisfactory answer to the question of their unity. On the other hand,
+it must be carefully noted what confusion this obscure and mystic dogma
+of the Trinity must necessarily cause in the minds of our children even
+in the earlier years of instruction. One morning they learn (in their
+religious instruction) that three times one are one, and the very next
+hour they are told in their arithmetic class that three times one are
+three. I remember well the reflection that this confusion led me to in
+my early school-days.
+
+For the rest, the "Trinity" is not an original element in Christianity;
+like most of the other Christian dogmas, it has been borrowed from
+earlier religions. Out of the sun-worship of the Chaldean magi was
+evolved the Trinity of Ilu, the mysterious source of the world; its
+three manifestations were Anu, primeval chaos; Bel, the architect of
+the world; and Aa, the heavenly light, the all-enlightening wisdom.
+In the Brahmanic religion the Trimurti is also conceived as a "divine
+unity" made up of three persons--Brahma (the creator), Vishnu (the
+sustainer), and Shiva (the destroyer). It would seem that in this
+and other ideas of a Trinity the "sacred number, three," as such--as
+a "symbolical number"--has counted for something. The three first
+Christian virtues--Faith, Hope, and Charity--form a similar _triad_.
+
+According to the _amphitheists_, the world is ruled by two different
+gods, a good and an evil principle, God and the Devil. They are engaged
+in a perpetual struggle, like rival emperors, or pope and anti-pope.
+The condition of the world is the result of this conflict. The
+loving God, or good principle, is the source of all that is good and
+beautiful, of joy and of peace. The world would be perfect if His work
+were not continually thwarted by the evil principle, the Devil; this
+being is the cause of all that is bad and hateful, of contradiction and
+of pain.
+
+Amphitheism is undoubtedly the most rational of all forms of belief in
+God, and the one which is least incompatible with a scientific view
+of the world. Hence we find it elaborated in many ancient peoples
+thousands of years before Christ. In ancient India Vishnu, the
+preserver, struggles with Shiva, the destroyer. In ancient Egypt the
+good Osiris is opposed by the wicked Typhon. The early Hebrews had a
+similar dualism of Aschera (or Keturah), the fertile mother-earth,
+and Elion (Moloch or Sethos), the stern heavenly father. In the Zend
+religion of the ancient Persians, founded by Zoroaster two thousand
+years before Christ, there is a perpetual struggle between Ormuzd, the
+good god of light, and Ahriman, the wicked god of darkness.
+
+In Christian mythology the Devil is scarcely less conspicuous as the
+adversary of the good deity, the tempter and seducer, the prince of
+hell, and lord of darkness. A personal devil was still an important
+element in the belief of most Christians at the beginning of the
+nineteenth century. Towards the middle of the century he was gradually
+eliminated by being progressively explained away, or he was restricted
+to the subordinate _rôle_ he plays as Mephistopheles in Goethe's great
+drama. To-day the majority of educated people look upon "belief in a
+personal devil" as a mediæval superstition, while "belief in God" (that
+is, the personal, good, and loving God) is retained as an indispensable
+element of religion. Yet the one belief is just as much (or as little)
+justified as the other. In any case, the much-lamented "imperfection of
+our earthly life," the "struggle for existence," and all that pertains
+to it, are explained much more simply and naturally by this struggle of
+a good and an evil god than by any other form of theism.
+
+The dogma of the unity of God may in some respects be regarded as the
+simplest and most natural type of theism; it is popularly supposed to
+be the most widely accepted element of religion, and to predominate
+in the ecclesiastical systems of civilized countries. In reality,
+that is not the case, because this alleged "monotheism" usually turns
+out on closer inquiry to be one of the other forms of theism we have
+examined, a number of subordinate deities being generally introduced
+besides the supreme one. Most of the religions which took a purely
+monotheistic stand-point have become more or less polytheistic in the
+course of time. Modern statistics assure us that of the one billion
+five hundred million men who people the earth the great majority
+are monotheists; of these, _nominally_, about six hundred millions
+are Brahma-Buddhists, five hundred millions are called Christians,
+two hundred millions are heathens (of various types), one hundred
+and eighty millions are Mohammedans, ten millions are Jews, and ten
+millions have no religion at all. However, the vast majority of
+these nominal monotheists have very confused ideas about the deity,
+or believe in a number of gods and goddesses besides the chief
+god--angels, devils, etc.
+
+The different forms which monotheism has assumed in the course of its
+polyphyletic development may be distributed in two groups--those of
+_naturalistic_ and _anthropistic_ monotheism. Naturalistic monotheism
+finds the embodiment of the deity in some lofty and dominating natural
+phenomenon. The sun, the deity of light and warmth, on whose influence
+all organic life insensibly and directly depends, was taken to be
+such a phenomenon many thousand years ago. Sun-worship (solarism,
+or heliotheism) seems to the modern scientist to be the best of all
+forms of theism, and the one which may be most easily reconciled
+with modern monism. For modern astrophysics and geogeny have taught
+us that the earth is a fragment detached from the sun, and that it
+will eventually return to the bosom of its parent. Modern physiology
+teaches us that the first source of organic life on the earth is the
+formation of protoplasm, and that this synthesis of simple inorganic
+substances, water, carbonic acid, and ammonia, only takes place under
+the influence of sunlight. On the primary evolution of the plasmodomous
+plants followed, secondarily, that of the plasmophagous animals, which
+directly or indirectly depend on them for nourishment; and the origin
+of the human race itself is only a later stage in the development of
+the animal kingdom. Indeed, the whole of our bodily and mental life
+depends, in the last resort, like all other organic life, on the
+light and heat rays of the sun. Hence in the light of pure reason,
+sun-worship, as a form of naturalistic monotheism, seems to have a much
+better foundation than the anthropistic worship of Christians and of
+other monotheists who conceive their god in human form. As a matter of
+fact, the sun-worshippers attained, thousands of years ago, a higher
+intellectual and moral standard than most of the other theists. When
+I was in Bombay, in 1881, I watched with the greatest sympathy the
+elevating rites of the pious Parsees, who, standing on the sea-shore,
+or kneeling on their prayer-rugs, offered their devotion to the sun at
+its rise and setting.[31]
+
+Moon-worship (lunarism and selenotheism) is of much less importance
+than sun-worship. There are a few uncivilized races that have adored
+the moon as their only deity, but it has generally been associated with
+a worship of the stars and the sun.
+
+The humanization of God, or the idea that the "Supreme Being" feels,
+thinks, and acts like man (though in a higher degree), has played a
+most important part, as _anthropomorphic monotheism_, in the history
+of civilization. The most prominent in this respect are the three
+great religions of the Mediterranean peoples--the old Mosaic religion,
+the intermediate Christian religion, and the younger Mohammedanism.
+These three great Mediterranean religions, all three arising on the
+east coast of the most interesting of all seas, and originating in an
+imaginative enthusiast of the Semitic race, are intimately connected,
+not only by this external circumstance of an analogous origin, but by
+many common features of their internal contents. Just as Christianity
+borrowed a good deal of its mythology directly from ancient Judaism, so
+Islam has inherited much from both its predecessors. All the three were
+originally monotheistic; all three were subsequently overlaid with a
+great variety of polytheistic features, in proportion as they extended,
+first along the coast of the Mediterranean with its heterogeneous
+population, and eventually into every part of the world.
+
+The Hebrew monotheism, as it was founded by Moses (about 1600 B.C.), is
+usually regarded as the ancient faith which has been of the greatest
+importance in the ethical and religious development of humanity.
+This high historical appreciation is certainly valid in the sense
+that the two other world-conquering Mediterranean religions issued
+from it; Christ was just as truly a pupil of Moses as Mohammed was
+afterwards of Christ. So also the New Testament, which has become the
+foundation of the belief of the highest civilized nations in the short
+space of nineteen hundred years, rests on the venerable basis of the
+Old Testament. The Bible, which the two compose, has had a greater
+influence and a wider circulation than any other book in the world.
+Even to-day the Bible--in spite of its curious mingling of the best and
+the worst elements--is in a certain sense the "book of books." Yet when
+we make an impartial and unprejudiced study of this notable historical
+source, we find it very different in several important respects from
+the popular impression. Here again modern criticism and history have
+come to certain conclusions which destroy the prevalent tradition in
+its very foundations.
+
+The monotheism which Moses endeavored to establish in the worship
+of Jehovah, and which the prophets--the philosophers of the Hebrew
+race--afterwards developed with great success, had at first to sustain
+a long and severe struggle with the dominant polytheism which was
+in possession. Jehovah, or Yahveh, was originally derived from the
+heaven-god, which, under the title of Moloch or Baal, was one of
+the most popular of the Oriental deities (the Sethos or Typhon of
+the Egyptians, and the Saturn or Cronos of the Greeks). There were,
+however, other gods in great favor with the Jewish people, and so the
+struggle with "idolatry" continued. Still, Jehovah was, in principle,
+the only God, explicitly claiming, in the first precept of the
+decalogue: "I am the Lord thy God; thou shalt have no other gods beside
+me."
+
+Christian monotheism shared the fate of its mother, Mosaism; it was
+generally only monotheistic in theory, while it degenerated practically
+into every kind of polytheism. In point of fact, monotheism was
+logically abandoned in the very dogma of the Trinity, which was adopted
+as an indispensable foundation of the Christian religion. The three
+persons, which are distinguished as Father, Son, and Holy Ghost, are
+three distinct individuals (and, indeed, anthropomorphic persons), just
+as truly as the three Indian deities of the Trimurti (Brahma, Vishnu,
+and Shiva) or the Trinity of the ancient Hebrews (Anu, Bel, and Aa).
+Moreover, in the most widely distributed form of Christianity the
+"virgin" mother of Christ plays an important part as a fourth deity;
+in many Catholic countries she is practically taken to be much more
+powerful and influential than the three male persons of the celestial
+administration. The cult of the madonna has been developed to such an
+extent in these countries that we may oppose it to the usual masculine
+form of monotheism as one of a feminine type. The "Queen of Heaven"
+becomes so prominent, as is seen in so many pictures and legends of the
+madonna, that the three male persons practically disappear.
+
+In addition, the imagination of the pious Christian soon came to
+increase this celestial administration by a numerous company of
+"saints" of all kinds, and bands of musical angels, who should see
+that "eternal life" should not prove too dull. The popes--the greatest
+charlatans that any religion ever produced--have constantly studied to
+increase this band of celestial satellites by repeated canonizations.
+This curious company received its most interesting acquisition in 1870,
+when the Vatican Council pronounced the popes, as the vicars of Christ,
+to be infallible, and thus raised them to a divine dignity. When we add
+the "personal Devil" that they acknowledge, and the "bad angels" who
+form his court, we have in modern Catholicism, still the most extensive
+branch of Christianity, a rich and variegated polytheism that dwarfs
+the Olympic family of the Greeks.
+
+Islam, or the Mohammedan monotheism, is the youngest and purest form of
+monotheism. When the young Mohammed (born 570) learned to despise the
+polytheistic idolatry of his Arabian compatriots, and became acquainted
+with Nestorian Christianity, he adopted its chief doctrines in a
+general way; but he could not bring himself to see anything more than
+a prophet in Christ, like Moses. He found in the dogma of the Trinity
+what every emancipated thinker finds on impartial reflection--an
+absurd legend which is neither reconcilable with the first principles
+of reason nor of any value whatever for our religious advancement. He
+justly regarded the worship of the immaculate mother of God as a piece
+of pure idolatry, like the veneration of pictures and images. The
+longer he reflected on it, and the more he strove after a purified idea
+of deity, the clearer did the certitude of his great maxim appear: "God
+is the only God"--there are no other gods beside him.
+
+Yet Mohammed could not free himself from the anthropomorphism of the
+God-idea. His one only God was an idealized, almighty man, like the
+stern, vindictive God of Moses, and the gentle, loving God of Christ.
+Still, we must admit that the Mohammedan religion has preserved the
+character of pure monotheism throughout the course of its historical
+development and its inevitable division much more faithfully than the
+Mosaic and Christian religions. We see that to-day, even externally,
+in its forms of prayer and preaching, and in the architecture and
+adornment of its mosques. When I visited the East for the first time,
+in 1873, and admired the noble mosques of Cairo, Smyrna, Brussa, and
+Constantinople, I was inspired with a feeling of real devotion by the
+simple and tasteful decoration of the interior, and the lofty and
+beautiful architectural work of the exterior. How noble and inspiring
+do these mosques appear in comparison with the majority of Catholic
+churches, which are covered internally with gaudy pictures and gilt,
+and are outwardly disfigured by an immoderate crowd of human and
+animal figures! Not less elevated are the silent prayers and the
+simple devotional acts of the Koran when compared with the loud,
+unintelligible verbosity of the Catholic Mass and the blatant music of
+their theatrical processions.
+
+Under the title of _mixotheism_ we may embrace all the forms of
+theistic belief which contain mixtures of religious notions of
+different, sometimes contradictory, kinds. In theory this most widely
+diffused type of religion is not recognized at all; in the concrete
+it is the most important and most notable of all. The vast majority
+of men who have religious opinions have always been, and still are,
+_mixotheists_; their idea of God is picturesquely compounded from the
+impressions received in childhood from their own sect, and a number
+of other impressions which are received later on, from contact with
+members of other religions, and which modify the earlier notions. In
+educated people there is also sometimes the modifying influence of
+philosophic studies in maturer years, and especially the unprejudiced
+study of natural phenomena, which reveals the futility of the theistic
+idea. The conflict of these contradictory impressions, which is
+very painful to a sensitive soul, and which often remains undecided
+throughout life, clearly shows the immense power of the _heredity_ of
+ancient myths on the one hand and the early _adaptation_ to erroneous
+dogmas on the other. The particular faith in which the child has been
+brought up generally remains in power, unless a "conversion" takes
+place subsequently, owing to the stronger influence of some other
+religion. But even in this supersession of one faith by another the new
+name, like the old one, proves to be merely an outward label covering
+a mixture of the most diverse opinions and errors. The greater part
+of those who call themselves Christians are not monotheists (as they
+think), but amphitheists, triplotheists, or polytheists. And the same
+must be said of Islam and Mosaism, and other monotheistic religions.
+Everywhere we find associated with the original idea of a "sole and
+triune God" later beliefs in a number of subordinate deities--angels,
+devils, saints, etc.--a picturesque assortment of the most diverse
+theistic forms.
+
+All the above forms of theism, in the proper sense of the word--whether
+the belief assumes a naturalistic or an anthropistic form--represent
+God to be an extramundane or a supernatural being. He is always opposed
+to the world, or nature, as an independent being; generally as its
+creator, sustainer, and ruler. In most religions he has the additional
+character of personality, or, to put it more definitely still, God as
+a person is likened to man. "In his gods man paints himself." This
+anthropomorphic conception of God as one who thinks, feels, and acts
+like man prevails with the great majority of theists, sometimes in a
+cruder and more naïve form, sometimes in a more refined and abstract
+degree. In any case the form of theosophy we have described is sure
+to affirm that God, the supreme being, is infinite in perfection, and
+therefore far removed from the imperfection of humanity. Yet, when we
+examine closely, we always find the same psychic or mental activity in
+the two. God feels, thinks, and acts as man does, although it be in an
+infinitely more perfect form.
+
+The _personal anthropism_ of God has become so natural to the majority
+of believers that they experience no shock when they find God
+personified in human form in pictures and statues, and in the varied
+images of the poet, in which God takes human form--that is, is changed
+into a vertebrate. In some myths, even, God takes the form of other
+mammals (an ape, lion, bull, etc.), and more rarely of a bird (eagle,
+dove, or stork), or of some lower vertebrate (serpent, crocodile,
+dragon, etc.).
+
+In the higher and more abstract forms of religion this idea of bodily
+appearance is entirely abandoned, and God is adored as a "pure spirit"
+without a body. "God is a spirit, and they who worship him must worship
+him in spirit and in truth." Nevertheless, the psychic activity of this
+"pure spirit" remains just the same as that of the anthropomorphic
+God. In reality, even this immaterial spirit is not conceived to be
+incorporeal, but merely invisible, gaseous. We thus arrive at the
+paradoxical conception of God as a _gaseous vertebrate_.
+
+
+II.--PANTHEISM
+
+Pantheism teaches that God and the world are one. The idea of God is
+identical with that of nature or substance. This pantheistic view is
+sharply opposed in principle to all the systems we have described, and
+to all possible forms of theism although there have been many attempts
+made from both sides to bridge over the deep chasm that separates the
+two. There is always this fundamental contradiction between them, that
+in theism God is opposed to nature as an _extramundane_ being, as
+creating and sustaining the world, and acting upon it from without,
+while in pantheism God, as an _intramundane_ being, is everywhere
+identical with nature itself, and is operative _within_ the world
+as "force" or "energy." The latter view alone is compatible with
+our supreme law--the law of substance. It follows necessarily that
+pantheism is _the world-system of the modern scientist_. There are,
+it is true, still a few men of science who contest this, and think it
+possible to reconcile the old theistic theory of human nature with the
+pantheistic truth of the law of substance. All these efforts rest on
+confusion or sophistry--when they are honest.
+
+As pantheism is a result of an advanced conception of nature in the
+civilized mind, it is naturally much younger than theism, the crudest
+forms of which are found in great variety in the uncivilized races of
+ten thousand years ago. We do, indeed, find the germs of pantheism in
+different religions at the very dawn of philosophy in the earliest
+civilized peoples (in India, Egypt, China, and Japan), several thousand
+years before the time of Christ; still, we do not meet a definite
+philosophical expression of it until the hylozoism of the Ionic
+philosophers, in the first half of the sixth century before Christ.
+All the great thinkers of this flourishing period of Hellenic thought
+are surpassed by the famous Anaximander, of Miletus, who conceived the
+essential unity of the infinite universe (_apeiron_) more profoundly
+and more clearly than his master, Thales, or his pupil, Anaximenes.
+Not only the great thought of the original unity of the cosmos and the
+development of all phenomena out of the all-pervading primitive matter
+found expression in Anaximander, but he even enunciated the bold idea
+of countless worlds in a periodic alternation of birth and death.
+
+Many other great philosophers of classical antiquity, especially
+Democritus, Heraclitus, and Empedocles, had, in the same or an
+analogous sense, a profound conception of this unity of nature and
+God, of body and spirit, which has obtained its highest expression
+in the law of substance of our modern monism. The famous Roman poet
+and philosopher, Lucretius Carus, has presented it in a highly poetic
+form in his poem "De Rerum Natura." However, this true pantheistic
+monism was soon entirely displaced by the mystic dualism of Plato, and
+especially by the powerful influence which the idealistic philosophy
+obtained by its blending with Christian dogmas. When the papacy
+attained to its spiritual despotism over the world, pantheism was
+hopelessly crushed; Giordano Bruno, its most gifted defender, was
+burned alive by the "Vicar of Christ" in the Campo dei Fiori at Rome on
+February 17, 1600.
+
+It was not until the middle of the seventeenth century that pantheism
+was exhibited in its purest form by the great Baruch Spinoza; he gave
+for the totality of things a definition of substance in which God
+and the world are inseparably united. The clearness, confidence, and
+consistency of Spinoza's monistic system are the more remarkable when
+we remember that this gifted thinker of two hundred and fifty years
+ago was without the support of all those sound empirical bases which
+have been obtained in the second half of the nineteenth century. We
+have already spoken, in the first chapter, of Spinoza's relation to the
+materialism of the eighteenth and the monism of the nineteenth century.
+The propagation of his views, especially in Germany, is due, above
+all, to the immortal works of our greatest poet and thinker, Wolfgang
+Goethe. His splendid _God and the World_, _Prometheus_, _Faust_, etc.,
+embody the great thoughts of pantheism in the most perfect poetic
+creations.
+
+Atheism affirms that there are no gods or goddesses, assuming that
+god means a personal, extramundane entity. This "godless world-system"
+substantially agrees with the monism or pantheism of the modern
+scientist; it is only another expression for it, emphasizing its
+negative aspect, the non-existence of any supernatural deity. In this
+sense Schopenhauer justly remarks: "Pantheism is only a polite form
+of atheism. The truth of pantheism lies in its destruction of the
+dualist antithesis of God and the world, in its recognition that the
+world exists in virtue of its own inherent forces. The maxim of the
+pantheist, 'God and the world are one,' is merely a polite way of
+giving the Lord God his _congé_."
+
+During the whole of the Middle Ages, under the bloody despotism of the
+popes, atheism was persecuted with fire and sword as a most pernicious
+system. As the "godless" man is plainly identified with the "wicked"
+in the Gospel, and is threatened--simply on account of his "want of
+faith"--with the eternal fires of hell, it was very natural that every
+good Christian should be anxious to avoid the suspicion of atheism.
+Unfortunately, the idea still prevails very widely. The atheistic
+scientist who devotes his strength and his life to the search for
+the truth, is freely credited with all that is evil; the theistic
+church-goer, who thoughtlessly follows the empty ceremonies of Catholic
+worship, is at once assumed to be a good citizen, even if there be no
+meaning whatever in his faith and his morality be deplorable. This
+error will only be destroyed when, in the twentieth century, the
+prevalent superstition gives place to rational knowledge and to a
+monistic conception of the unity of God and the world.
+
+
+
+
+CHAPTER XVI
+
+KNOWLEDGE AND BELIEF
+
+    The Knowledge of the Truth and Its Sources: the Activity of the
+    Senses and the Association of Presentations--Organs of Sense and
+    Organs of Thought--Sense-Organs and their Specific Energy--Their
+    Evolution--The Philosophy of Sensibility--Inestimable Value of the
+    Senses--Limits of Sensitive Knowledge--Hypothesis and Faith--Theory
+    and Faith--Essential Difference of Scientific (Natural) and
+    Religious (Supernatural) Faith--Superstition of Savage and of
+    Civilized Races--Confessions of Faith--Unsectarian Schools--The
+    Faith of Our Fathers--Spiritism--Revelation
+
+
+Every effort of genuine science makes for a knowledge of the truth. Our
+only real and valuable knowledge is a knowledge of nature itself, and
+consists of presentations which correspond to external things. We are
+incompetent, it is true, to penetrate into the innermost nature of this
+real world--the "thing in itself"--but impartial critical observation
+and comparison inform us that, in the normal action of the brain and
+the organs of sense, the impressions received by them from the outer
+world are the same in all rational men, and that in the normal function
+of the organs of thought certain presentations are formed which are
+everywhere the same. These presentations we call _true_, and we are
+convinced that their content corresponds to the knowable aspect of
+things. We _know_ that these facts are not imaginary, but real.
+
+All knowledge of the truth depends on two different, but intimately
+connected, groups of human physiological functions: firstly, on the
+_sense-impressions_ of the object by means of sense-action, and,
+secondly, on the combination of these impressions by an association
+into _presentations_ in the subject. The instruments of sensation are
+the sense-organs (_sensilla_ or _aestheta_); the instruments which
+form and link together the presentations are the organs of thought
+(_phroneta_). The latter are part of the central, and the former part
+of the peripheral, nervous system--that important and elaborate system
+of organs in the higher animals which alone effects their entire
+psychic activity.
+
+Man's sense-activity, which is the starting-point of all knowledge,
+has been slowly and gradually developed from that of his nearest
+mammal relatives, the primates. The sense-organs are of substantially
+the same construction throughout this highest animal group, and their
+function takes place always according to the same physical and chemical
+laws. They have had the same historical development in all cases. In
+the mammals, as in the case of all other animals, the _sensilla_ were
+originally parts of the skin; the sensitive cells of the epidermis are
+the sources of all the different sense-organs, which have acquired
+their specific energy by adaptation to different stimuli (light, heat,
+sound, chemical action, etc.). The rod-cells in the retina of the eye,
+the auditory cells in the cochlea of the ear, the olfactory cells in
+the nose, and the taste-cells on the tongue, are all originally derived
+from the simple, indifferent cells of the epidermis, which cover the
+entire surface of the body. This significant fact can be directly
+proved by observation of the embryonic development of man or any of the
+higher animals. And from this ontogenetic fact we confidently infer,
+in virtue of the great biogenetic law, the important phylogenetic
+proposition, that in the long historical evolution of our ancestors,
+likewise, the higher sense-organs with their specific energies were
+originally derived from the epidermis of lower animals, from a simple
+layer of cells which had no trace of such differentiated sensilla.
+
+A particular importance attaches to the circumstance that different
+nerves are qualified to perceive different properties of the
+environment, and these only. The optic nerve accomplishes only the
+perception of light, the auditory nerve the perception of sound, the
+olfactory nerve the perception of smell, and so on. No matter what
+stimuli impinge on and irritate a given sense-organ, its reaction
+is always of the same character. From this specific energy of the
+sense-nerves, which was first fully appreciated by Johannes Müller,
+very erroneous inferences have been drawn, especially in favor of a
+dualistic and _à priori_ theory of knowledge. It has been affirmed
+that the brain, or the soul, only perceives a certain condition of the
+stimulated nerve, and that, consequently, no conclusion can be drawn
+from the process as to the existence and nature of the stimulating
+environment. Sceptical philosophy concluded that the very existence of
+an outer world is doubtful, and extreme idealism went on positively to
+deny it, contending that things only exist in our impressions of them.
+
+In opposition to these erroneous views, we must recall the fact that
+the "specific energy" was not originally an innate, special quality of
+the various nerves, but it has arisen by adaptation to the particular
+activity of the epidermic cells in which they terminate. In harmony
+with the great law of "division of labor" the originally indifferent
+"sense-cells of the skin" undertook different tasks, one group of them
+taking over the stimulus of the light rays, another the impress of the
+sound waves, a third the chemical impulse of odorous substances, and so
+on. In the course of a very long period these external stimuli effected
+a gradual change in the physiological, and later in the morphological,
+properties of these parts of the epidermis, and there was a correlative
+modification of the sensitive nerves which conduct the impressions they
+receive to the brain. Selection improved, step by step, such particular
+modifications as proved to be useful, and thus eventually, in the
+course of many million years, created those wonderful instruments,
+the eye and the ear, which we prize so highly; their structure is
+so remarkably purposive that they might well lead to the erroneous
+assumption of a "creation on a preconceived design." The peculiar
+character of each sense-organ and its specific nerve has thus been
+gradually evolved by use and exercise--that is, by _adaptation_--and
+has then been transmitted by _heredity_ from generation to generation.
+Albrecht Rau has thoroughly established this view in his excellent
+work on _Sensation and Thought_, a physiological inquiry into the
+nature of the human understanding (1896). It points out the correct
+significance of Müller's law of specific sense-energies, adding
+searching investigations into their relation to the brain, and in the
+last chapter there is an able "philosophy of sensitivity" based on the
+ideas of Ludwig Feuerbach. I thoroughly agree with his convincing work.
+
+Critical comparison of sense-action in man and the other vertebrates
+has brought to light a number of extremely important facts, the
+knowledge of which we owe to the penetrating research of the
+nineteenth century, especially of the second half of the century. This
+is particularly true of the two most elaborate "æsthetic" organs,
+the eye and the ear. They present a different and more complicated
+structure in the vertebrates than in the other animals, and have also
+a characteristic development in the embryo. This typical ontogenesis
+and structure of the sensilla of all the vertebrates is only explained
+by _heredity_ from a common ancestor. Within the vertebrate group,
+however, we find a great variety of structure in points of detail, and
+this is due to _adaptation_ to their manner of life on the part of the
+various species, to the increasing or diminishing use of various parts.
+
+In respect of the structure of his sense-organs man is by no means
+the most perfect and most highly-developed vertebrate. The eye of the
+eagle is much keener, and can distinguish small objects at a distance
+much more clearly than the human eye. The hearing of many mammals,
+especially of the carnivora, ungulata, and rodentia of the desert, is
+much more sensitive than that of man, and perceives slight noises at a
+much greater distance; that may be seen at a glance by their large and
+very sensitive cochlea. Singing birds have attained a higher grade of
+development, even in respect of musical endowment, than the majority of
+men. The sense of smell is much more developed in most of the mammals,
+especially in the carnivora and the ungulata, than in man; if the dog
+could compare his own fine scent with that of man, he would look down
+on us with compassion. Even with regard to the lower senses--taste,
+sex-sense, touch, and temperature--man has by no means reached the
+highest stage in every respect.
+
+We can naturally only pass judgment on the sensations which we
+ourselves experience. However, anatomy informs us of the presence in
+the bodies of many animals of other senses than those we are familiar
+with. Thus fishes and other lower aquatic vertebrates have peculiar
+sensilla in the skin which are in connection with special sense-nerves.
+On the right and left sides of the fish's body there is a long canal,
+branching into a number of smaller canals at the head. In this "mucous
+canal" there are nerves with numerous branches, the terminations of
+which are connected with peculiar nerve-aggregates. This extensive
+epidermic sense-organ probably serves for the perception of changes in
+the pressure, or in other properties, of the water. Some groups are
+distinguished by the possession of other peculiar sensilla, the meaning
+of which is still unknown to us.
+
+But it is already clear from the above facts that our human
+sense-activity is limited, not only in quantity, but in quality also.
+We can thus only perceive with our senses, especially with the eye
+and the sense of touch, a part of the qualities of the objects in our
+environment. And even this partial perception is incomplete, in the
+sense that our organs are imperfect, and our sensory nerves, acting
+as interpreters, communicate to the brain only a translation of the
+impressions received.
+
+However, this acknowledged imperfection of our senses should not
+prevent us from recognizing their instruments, and especially the eye,
+to be organs of the highest type; together with the thought-organs in
+the brain, they are nature's most valuable gift to man. Very truly does
+Albrecht Rau say: "All science is sensitive knowledge in the ultimate
+analysis; it does not deny, but interpret, the data of the senses.
+The senses are our first and best friends. Long before the mind is
+developed the senses tell man what he must do and avoid. He who makes
+a general disavowal of the senses in order to meet their dangers acts
+as thoughtlessly and as foolishly as the man who plucks out his eyes
+because they once fell on shameful things, or the man who cuts off
+his hand lest at any time it should reach out to the goods of his
+neighbor." Hence Feuerbach is quite right in calling all philosophies,
+religions, and systems which oppose the principle of sense-action not
+only erroneous, but really pernicious. Without the senses there is
+no knowledge--"_Nihil est in intellectu, quod non fuerit in sensu_,"
+as Locke said. Twenty years ago I pointed out, in my chapter "On the
+Origin and Development of the Sense-Organs,"[32] the great service of
+Darwinism in giving us a profounder knowledge and a juster appreciation
+of the senses.
+
+The thirst for knowledge of the educated mind is not contented with
+the defective acquaintance with the outer world which is obtained
+through our imperfect sense-organs. He endeavors to build up the
+sense-impressions which they have brought him into valuable knowledge.
+He transforms them into specific sense-perceptions in the sense-centres
+of the cortex of the brain, and combines them into presentations,
+by association, in the thought-centres. Finally, by a further
+concatenation of the groups of presentations he attains to connected
+knowledge. But this knowledge remains defective and unsatisfactory
+until the imagination supplements the inadequate power of combination
+of the intelligence, and, by the association of stored-up images,
+unites the isolated elements into a connected whole. Thus are produced
+new general presentative images, and these suffice to interpret the
+facts perceived and satisfy "reason's feeling of causality."
+
+The presentations which fill up the gaps in our knowledge, or take its
+place, may be called, in a broad sense, "faith." That is what happens
+continually in daily life. When we are not sure about a thing we say, I
+believe it. In this sense we are compelled to make use of faith even in
+science itself; we conjecture or assume that a certain relation exists
+between two phenomena, though we do not know it for certain. If it is
+a question of a _cause_, we form a _hypothesis_; though in science
+only such hypotheses are admitted as lie within the sphere of human
+cognizance, and do not contradict known facts. Such hypotheses are, for
+instance--in physics the theory of the vibratory movement of ether, in
+chemistry the hypothesis of atoms and their affinity, in biology the
+theory of the molecular structure of living protoplasm, and so forth.
+
+The explanation of a great number of connected phenomena by the
+assumption of a common cause is called a _theory_. Both in theory and
+hypothesis "faith" (in the scientific sense) is indispensable; for
+here again it is the imagination that fills up the gaps left by the
+intelligence in our knowledge of the connection of things. A theory,
+therefore, must always be regarded only as an approximation to the
+truth; it must be understood that it may be replaced in time by another
+and better-grounded theory. But, in spite of this admitted uncertainty,
+theory is indispensable for all true science; it elucidates facts by
+postulating a cause for them. The man who renounces theory altogether,
+and seeks to construct a pure science with certain facts alone
+(as often happens with wrong-headed representatives of our "exact
+sciences"), must give up the hope of any knowledge of causes, and,
+consequently, of the satisfaction of reason's demand for causality.
+
+The theory of gravitation in astronomy (Newton), the nebular theory
+in cosmogony (Kant and Laplace), the principle of energy in physics
+(Meyer and Helmholtz), the atomic theory in chemistry (Dalton), the
+vibratory theory in optics (Huyghens), the cellular theory in histology
+(Schleiden and Schwann), and the theory of descent in biology (Lamarck
+and Darwin), are all important theories of the first rank; they explain
+a whole world of natural phenomena by the assumption of a common cause
+for all the several facts of their respective provinces, and by showing
+that all the phenomena thereof are inter-connected and controlled by
+laws which issue from this common cause. Yet the cause itself may
+remain obscure in character, or be merely a "provisional hypothesis."
+The "force of gravity" in the theory of gravitation and in cosmogony,
+"energy" itself in its relation to matter, the "ether" of optics
+and electricity, the "atom" of the chemist, the living "protoplasm"
+of histology, the "heredity" of the evolutionist--these and similar
+conceptions of other great theories may be regarded by a sceptical
+philosophy as "mere hypotheses" and the outcome of scientific "faith,"
+yet they are indispensable for us, until they are replaced by better
+hypotheses.
+
+The dogmas which are used for the explanation of phenomena in the
+various religions, and which go by the name of "faith" (in the narrower
+sense), are of a very different character from the forms of scientific
+faith we have enumerated. The two types, however--the "natural"
+faith of science and the "supernatural" faith of religion--are not
+infrequently confounded, so that we must point out their fundamental
+difference. Religious faith means always belief in a miracle, and as
+such is in hopeless contradiction with the natural faith of reason.
+In opposition to reason it postulates supernatural agencies, and,
+therefore, may be justly called superstition. The essential difference
+of this superstition from rational faith lies in the fact that it
+assumes supernatural forces and phenomena, which are unknown and
+inadmissible to science, and which are the outcome of illusion and
+fancy; moreover, superstition contradicts the well-known laws of
+nature, and is therefore _irrational_.
+
+Owing to the great progress of ethnology during the century, we
+have learned a vast quantity of different kinds and practices of
+superstition, as they still survive in uncivilized races. When they are
+compared with each other and with the mythological notion of earlier
+ages, a manifold analogy is discovered, frequently a common origin, and
+eventually one simple source for them all. This is found in the "demand
+of causality in reason," in the search for an explanation of obscure
+phenomena by the discovery of a cause. That applies particularly to
+such phenomena as threaten us with danger and excite fear, like thunder
+and lightning, earthquakes, eclipses, etc. The demand for a causal
+explanation of such phenomena is found in uncivilized races of the
+lowest grade, transmitted from their primate ancestors by heredity. It
+is even found in many other vertebrates. When a dog barks at the full
+moon, or at a ringing bell, of which it sees the hammer moving, or at a
+flag that flutters in the breeze, it expresses not only fear, but also
+the mysterious impulse to learn the cause of the obscure phenomenon.
+The crude beginnings of religion among primitive races spring partly
+from this hereditary superstition of their primate ancestors, and
+partly from the worship of ancestors, from various emotional impulses,
+and from habits which have become traditional.
+
+The religious notions of modern civilized peoples, which they esteem
+so highly, profess to be on a much higher level than the "crude
+superstition" of the savage; we are told of the great advance which
+civilization has made in sweeping it aside. That is a great mistake.
+Impartial comparison and analysis show that they only differ in
+their special "form of faith" and the outer shell of their creed.
+In the clear light of reason the refined faith of the most liberal
+ecclesiastical religion--inasmuch as it contradicts the known and
+inviolable laws of nature--is no less irrational a superstition than
+the crude spirit-faith of primitive fetichism on which it looks down
+with proud disdain.
+
+And if, from this impartial stand-point, we take a critical glance at
+the kinds of faith that prevail to-day in civilized countries, we find
+them everywhere saturated with traditional superstition. The Christian
+belief in Creation, the Trinity, the Immaculate Conception, the
+Redemption, the Resurrection and Ascension of Christ, and so forth, is
+just as purely imaginative as the belief in the various dogmas of the
+Mohammedan, Mosaic, Buddhistic, and Brahmanic religions, and is just
+as incapable of reconciliation with a rational knowledge of nature.
+Each of these religions is for the sincere believer an indisputable
+truth, and each regards the other as heresy and damnable error. The
+more confidently a particular sect considers itself "the only ark
+of salvation," and the more ardently this conviction is cherished,
+the more zealously does it contend against all other sects and give
+rise to the fearful religious wars that form the saddest pages in the
+book of history. And all the time the unprejudiced "critique of pure
+reason" teaches us that all these different forms of faith are equally
+false and irrational, mere creatures of poetic fancy and uncritical
+tradition. Rational science must reject them all alike as the outcome
+of superstition.
+
+The incalculable injury which irrational superstition has done
+to credulous humanity is conspicuously revealed in the ceaseless
+conflict of confessions of faith. Of all the wars which nations have
+waged against each other with fire and sword the religious wars have
+been the bloodiest; of all the forms of discord that have shattered
+the happiness of families and of individuals those that arise from
+religious differences are still the most painful. Think of the millions
+who have lost their lives in Christian persecutions, in the religious
+conflicts of Islam and of the Reformation, by the Inquisition, and
+under the charge of witchcraft. Or think of the still greater number
+of luckless men who, through religious differences, have been plunged
+into family troubles, have lost the esteem of their fellow-citizens
+and their position in the community, or have even been compelled to
+fly from their country. The official confession of faith becomes most
+pernicious of all when it is associated with the political aims of
+a modern state, and is enforced as "religious instruction" in our
+schools. The child's mind is thus early diverted from the pursuit of
+the truth and impregnated with superstition. Every friend of humanity
+should do all in his power to promote unsectarian schools as one of the
+most valuable institutions of the modern state.
+
+The great value which is, none the less, still very widely attached
+to sectarian instruction is not only due to the compulsion of a
+reactionary state and its dependence on a dominant clericalism, but
+also to the weight of old traditions and "emotional cravings" of
+various kinds. One of the strongest of these is the devout reverence
+which is extended everywhere to sectarian tradition, to the "faith
+of our fathers." In thousands of stories and poems fidelity to it
+is extolled as a spiritual treasure and a sacred duty. Yet a little
+impartial study of the history of faith suffices to show the absurdity
+of the notion. The dominant evangelical faith of the second half of
+the nineteenth century is essentially different from that of the first
+half, and this again from that of the eighteenth century. The faith of
+the eighteenth century diverges considerably from the "faith of our
+fathers" of the seventeenth, and still more from that of the sixteenth,
+century. The Reformation, releasing enslaved reason from the tyranny of
+the popes, is naturally regarded by them as darkest heresy; but even
+the faith of the papacy itself had been completely transformed in the
+course of a century. And how different is the faith of the Christian
+from that of his heathen ancestors. Every man with some degree of
+independent thought frames a more or less personal religion for
+himself, which is always different from that of his fathers; it depends
+largely on the general condition of thought in his day. The further we
+go back in the history of civilization, the more clearly do we find
+this esteemed "faith of our fathers" to be an indefensible superstition
+which is undergoing continual transformation.
+
+One of the most remarkable forms of superstition, which still takes a
+very active part in modern life, is _spiritism_. It is a surprising
+and a lamentable fact that millions of educated people are still
+dominated by this dreary superstition; even distinguished scientists
+are entangled in it. A number of spiritualist journals spread the
+faith far and wide, and our "superior circles" do not scruple to hold
+_séances_ in which "spirits" appear, rapping, writing, giving messages
+from "the beyond," and so on. It is a frequent boast of spiritists that
+even eminent men of science defend their superstition. In Germany, A.
+Zöllner and Fechner are quoted as instances; in England, Wallace and
+Crookes. The regrettable circumstance that physicists and biologists
+of such distinction have been led astray by spiritism is accounted
+for, partly by their excess of imagination and defect of critical
+faculty, and partly by the powerful influence of dogmas which a
+religious education imprinted on the brain in early youth. Moreover,
+it was precisely through the famous _séances_ at Leipzig, in which the
+physicists, Zöllner, Fechner, and Wilhelm Weber, were imposed on by
+the clever American conjuror, Slade, that the fraud of the latter was
+afterwards fully exposed; he was discovered to be a common impostor.
+In other cases, too, where the alleged marvels of spiritism have been
+thoroughly investigated, they have been traced to a more or less clever
+deception; the mediums (generally of the weaker sex) have been found to
+be either smart swindlers or nervous persons of abnormal irritability.
+Their supposed gift of "telepathy" (or "action at a distance of thought
+without material medium") has no more existence than the "voices" or
+the "groans" of spirits, etc. The vivid pictures which Carl du Prel, of
+Munich, and other spiritists give of their phenomena must be regarded
+as the outcome of a lively imagination, together with a lack of
+critical power and of knowledge of physiology.
+
+The majority of religions have, in spite of their great differences,
+one common feature, which is, at the same time, one of their strongest
+supports in many quarters. They declare that they can elucidate the
+problem of existence, the solution of which is beyond the natural power
+of reason, by the supernatural way of revelation; from that they derive
+the authority of the dogmas which in the guise of "divine laws" control
+morality and the practical conduct of life. "Divine" inspirations of
+that kind form the basis of many myths and legends, the human origin of
+which is perfectly clear. It is true that the God who reveals himself
+does not always appear in human shape, but in thunder and lightning,
+storm and earthquake, fiery bush or menacing cloud. But the revelation
+which he is supposed to bring to the credulous children of men is
+always anthropomorphic; it invariably takes the form of a communication
+of ideas or commands which are formulated and expressed precisely as is
+done in the normal action of the human brain and larynx. In the Indian
+and Egyptian religions, in the mythologies of Greece and Rome, in the
+Old and the New Testaments, the gods think, talk, and act just as men
+do; the revelations, in which they are supposed to unveil for us the
+secrets of existence and the solution of the great world-enigma, are
+creations of the human imagination. The "truth" which the credulous
+discover in them is a human invention; the "childlike faith" in these
+irrational revelations is mere superstition.
+
+The true revelation--that is, the true source of rational knowledge--is
+to be sought in nature alone. The rich heritage of truth which forms
+the most valuable part of human culture is derived exclusively from
+the experiences acquired in a searching study of nature, and from the
+rational conclusions which it has reached by the just association of
+these empirical presentations. Every intelligent man with normal brain
+and senses finds this true revelation in nature on impartial study, and
+thus frees himself from the superstition with which the "revelations"
+of religion had burdened him.
+
+
+
+
+CHAPTER XVII
+
+SCIENCE AND CHRISTIANITY
+
+    Increasing Opposition between Modern Science and Christian
+    Theology--The Old and the New Faith--Defence of Rational Science
+    against the Attacks of Christian Superstition, especially against
+    Catholicism--Four Periods in the Evolution of Christianity:
+    I. Primitive Christianity (the First Three Centuries)--The
+    Four Canonical Gospels--The Epistles of Paul--II. The Papacy
+    (Ultramontane Christianity)--Retrogression of Civilization in the
+    Middle Ages--Ultramontane Falsification of History--The Papacy and
+    Science--The Papacy and Christianity--III. The Reformation--Luther
+    and Calvin--The Year of Emancipation--IV. The Pseudo-Christianity
+    of the Nineteenth Century--The Papal Declaration of War against
+    Reason and Science: (_a_) Infallibility, (_b_) The Encyclica, (_c_)
+    The Immaculate Conception
+
+
+One of the most distinctive features of the expiring century is
+the increasing vehemence of the opposition between science and
+Christianity. That is both natural and inevitable. In the same
+proportion in which the victorious progress of modern science has
+surpassed all the scientific achievements of earlier ages has the
+untenability been proved of those mystic views which would subdue
+reason under the yoke of an alleged revelation; and the Christian
+religion belongs to that group. The more solidly modern astronomy,
+physics, and chemistry have established the sole dominion of inflexible
+natural laws in the universe at large, and modern botany, zoology,
+and anthropology have proved the validity of those laws in the entire
+kingdom of organic nature, so much the more strenuously has the
+Christian religion, in association with dualistic metaphysics, striven
+to deny the application of these natural laws in the province of the
+so-called "spiritual life"--that is, in one section of the physiology
+of the brain.
+
+No one has more clearly, boldly, and unanswerably enunciated this
+open and irreconcilable opposition between the modern scientific and
+the outworn Christian view than David Friedrich Strauss, the greatest
+theologian of the nineteenth century. His last work, _The Old Faith
+and the New_, is a magnificent expression of the honest conviction of
+all educated people of the present day who understand this unavoidable
+conflict between the discredited, dominant doctrines of Christianity
+and the illuminating, rational revelation of modern science--all
+those who have the courage to defend the right of reason against the
+pretensions of superstition, and who are sensible of the philosophic
+demand for a unified system of thought. Strauss, as an honorable and
+courageous free-thinker, has expounded far better than I could the
+principal points of difference between "the old and the new faith."
+The absolute irreconcilability of the opponents and the inevitability
+of their struggle ("for life or death") have been ably presented on
+the philosophic side by E. Hartmann, in his interesting work on _The
+Self-Destruction of Christianity_.
+
+When the works of Strauss and Feuerbach and _The History of the
+Conflict between Religion and Science_ of J. W. Draper have been read,
+it may seem superfluous for us to devote a special chapter to the
+subject. Yet we think it useful, and even necessary for our purpose,
+to cast a critical glance at the historical course of this great
+struggle; especially seeing that the attacks of the "Church militant"
+on science in general, and on the theory of evolution in particular,
+have become extremely bitter and menacing of late years. Unfortunately,
+the mental relaxation which has lately set in, and the rising flood of
+reaction in the political, social, and ecclesiastical world, are only
+too well calculated to give point to those dangers. If any one doubts
+it, he has only to look over the conduct of Christian synods and of the
+German Reichstag during the last few years. Quite in harmony are the
+recent efforts of many secular governments to get on as good a footing
+as possible with the "spiritual regiment," their deadly enemy--that
+is, to submit to its yoke. The two forces find a common aim in the
+suppression of free thought and free scientific research, for the
+purpose of thus more easily securing a complete despotism.
+
+Let us first emphatically protest that it is a question for us of the
+necessary defence of science and reason against the vigorous attacks
+of the Christian Church and its vast army, not of an unprovoked
+attack of science on religion. And, in the first place, our defence
+must be prepared against Romanism or Ultramontanism. This "one ark
+of salvation," this Catholic Church "destined for all," is not only
+much larger and more powerful than the other Christian sects, but it
+has the exceptional advantage of a vast, centralized organization
+and an unrivalled political ability. Men of science are often heard
+to say that the Catholic superstition is no more astute than the
+other forms of supernatural faith, and that all these insidious
+institutions are equally inimical to reason and science. As a matter
+of general theoretical principle the statement may pass, but it is
+certainly wrong when we look to its practical side. The deliberate and
+indiscriminate attacks of the ultramontane Church on science, supported
+by the apathy and ignorance of the masses, are, on account of its
+powerful organization, much more severe and dangerous than those of
+other religions.
+
+In order to appreciate correctly the extreme importance of Christianity
+in regard to the entire history of civilization, and particularly
+its fundamental opposition to reason and science, we must briefly
+run over the principal stages of its historical evolution. It may be
+divided into four periods: (1) primitive Christianity (the first three
+centuries), (2) papal Christianity (twelve centuries, from the fourth
+to the fifteenth), (3) the Reformation (three centuries, from the
+sixteenth to the eighteenth), and (4) modern pseudo-Christianity.
+
+
+I.--PRIMITIVE CHRISTIANITY
+
+Primitive Christianity embraces the first three centuries. Christ
+himself, the noble prophet and enthusiast, so full of the love of
+humanity, was far below the level of classical culture; he knew nothing
+beyond the Jewish traditions; he has not left a single line of writing.
+He had, indeed, no suspicion of the advanced stage to which Greek
+philosophy and science had progressed five hundred years before.
+
+All that we know of him and of his original teaching is taken from the
+chief documents of the New Testament--the four gospels and the Pauline
+epistles. As to the four canonical gospels, we now know that they were
+selected from a host of contradictory and forged manuscripts of the
+first three centuries by the three hundred and eighteen bishops who
+assembled at the Council of Nicæa in 327. The entire list of gospels
+numbered forty; the canonical list contains four. As the contending
+and mutually abusive bishops could not agree about the choice, they
+determined to leave the selection to a miracle. They put all the books
+(according to the _Synodicon_ of Pappus) together underneath the
+altar, and prayed that the apocryphal books, of human origin, might
+remain there, and the genuine, inspired books might be miraculously
+placed on the table of the Lord. And that, says tradition, really
+occurred! The three synoptic gospels (Matthew, Mark, and Luke--all
+written _after_ them, not _by_ them, at the beginning of the second
+century) and the very different fourth gospel (ostensibly "after"
+John, written about the middle of the second century) leaped on the
+table, and were thenceforth recognized as the inspired (with their
+thousand mutual contradictions) foundations of Christian doctrine. If
+any modern "unbeliever" finds this story of the "leap of the sacred
+books" incredible, we must remind him that it is just as credible as
+the table-turning and spirit-rapping that are believed to take place
+to-day by millions of educated people; and that hundreds of millions of
+Christians believe just as implicitly in their personal immortality,
+their "resurrection from the dead," and the Trinity of God--dogmas that
+contradict pure reason no more and no less than that miraculous bound
+of the gospel manuscripts.
+
+The most important sources after the gospels are the fourteen separate
+(and generally forged) epistles of Paul. The genuine Pauline epistles
+(_three_ in number, according to recent criticism--to the Romans,
+Galatians, and Corinthians) were written before the canonical gospels,
+and contain less incredible miraculous matter than they. They are
+also more concerned than the gospels to adjust themselves with a
+rational view of the world. Hence the advanced theology of modern times
+constructs its "ideal Christianity" rather on the base of the Pauline
+epistles than on the gospels, so that it has been called "Paulinism."
+
+The remarkable personality of Paul, who possessed much more culture
+and practical sense than Christ, is extremely interesting, from the
+anthropological point of view, from the fact that the racial origin
+of the two great religious founders is very much the same. Recent
+historical investigation teaches that Paul's father was of Greek
+nationality, and his mother of Jewish.[33] The half-breeds of these two
+races, which are so very distant in origin (although they are branches
+of the same species, the _homo mediterraneus_), are often distinguished
+by a happy blending of talents and temperament, as we find in many
+recent and actual instances. The plastic Oriental imagination and the
+critical Western reason often admirably combine and complete each
+other. That is visible in the Pauline teaching, which soon obtained a
+greater influence than the earliest Christian notions. Hence it is not
+incorrect to consider Paulinism a new phenomenon, of which the father
+was the philosophy of the Greeks, and the mother the religion of the
+Jews. Neoplatonism is an analogous combination.
+
+As to the real teaching and aims of Christ (and as to many important
+aspects of his life) the views of conflicting theologians diverge
+more and more, as historical criticism (Strauss, Feuerbach, Baur,
+Renan, etc.) puts the accessible facts in their true light, and draws
+impartial conclusions from them. Two things, certainly, remain beyond
+dispute--the lofty principle of universal charity and the fundamental
+maxim of ethics, the "golden rule," that issues therefrom; both,
+however, existed in theory and in practice centuries before the time
+of Christ (cf. chap. xix.). For the rest, the Christians of the early
+centuries were generally pure Communists, sometimes "Social Democrats,"
+who, according to the prevailing theory in Germany to-day, ought to
+have been exterminated with fire and sword.
+
+
+II.--PAPAL CHRISTIANITY
+
+Latin Christianity, variously called Papistry, Romanism, Vaticanism,
+Ultramontanism, or the Roman Catholic Church, is one of the most
+remarkable phenomena in the history of civilized man; in spite of
+the storms that have swept over it, it still exerts a most powerful
+influence. Of the four hundred and ten million Christians who are
+scattered over the earth the majority--that is, two hundred and
+twenty-five millions--are Roman Catholics; there are seventy-five
+million Greek Catholics and one hundred and ten million Protestants.
+During a period of one thousand two hundred years, from the fourth to
+the sixteenth century, the papacy has almost absolutely controlled and
+tainted the spiritual life of Europe; on the other hand, it has won but
+little territory from the ancient religions of Asia and Africa. In Asia
+Buddhism still counts five hundred and three million followers, the
+Brahmanic religion one hundred and thirty-eight millions, and Islam one
+hundred and twenty millions.
+
+It is the despotism of the papacy that lent its darkest character to
+the Middle Ages; it meant death to all freedom of mental life, decay
+to all science, corruption to all morality. From the noble height to
+which the life of the human mind had attained in classical antiquity,
+in the centuries before Christ and the first century after Christ,
+it soon sank, under the rule of the papacy, to a level which, in
+respect of the knowledge of the truth, can only be termed barbarism.
+It is often protested that other aspects of mental life--poetry and
+architecture, scholastic learning and patristic philosophy--were richly
+developed in the Middle Ages. But this activity was in the service of
+the Church; it did not tend to the cultivation, but to the suppression,
+of free mental research. The exclusive preparing for an unknown
+eternity beyond the tomb, the contempt of nature, the withdrawal from
+the study of it, which are essential elements of Christianity, were
+urged as a sacred duty by the Roman hierarchy. It was not until the
+beginning of the sixteenth century that a change for the better came in
+with the Reformation.
+
+It is impossible for us here to describe the pitiful retrogression
+of culture and morality during the twelve centuries of the spiritual
+despotism of Rome. It is very pithily expressed in a saying of the
+greatest and the ablest of the Hohenzollerns; Frederick the Great
+condensed his judgment in the phrase that the study of history led
+one to think that from Constantine to the date of the Reformation the
+whole world was insane. L. Büchner has given us an admirable, brief
+description of this "period of insanity" in his work on _Religious
+and Scientific Systems_. The reader who desires a closer acquaintance
+with the subject would do well to consult the historical works of
+Ranke, Draper, Kolb, Svoboda, etc. The truthful description of the
+awful condition of the Christian Middle Ages, which is given by these
+and other unprejudiced historians, is confirmed by all the reliable
+sources of investigation, and by the historical monuments which
+have come down from the saddest period of human history. Educated
+Catholics, who are sincere truth-seekers, cannot be too frequently
+recommended to study these historical sources for themselves. This is
+the more necessary as ultramontane literature has still a considerable
+influence. The old trick of deceiving the faithful by a complete
+reversal of facts and an invention of miraculous circumstances is
+still worked by it with great success. We will only mention Lourdes
+and the "Holy Coat" of Trêves. The ultramontane professor of history
+at Frankfurt, Johannes Janssen, affords a striking example of the
+length they will go in distorting historical truth; his much-read works
+(especially his _History of the German People since the Middle Ages_)
+are marred by falsification to an incredible extent. The untruthfulness
+of these Jesuitical productions is on a level with the credulity and
+the uncritical judgment of the simple German nation that takes them for
+gospel.
+
+One of the most interesting of the historical facts which clearly prove
+the evil of the ultramontane despotism is its vigorous and consistent
+struggle with science. This was determined on, in principle, from the
+very beginning of Christianity, inasmuch as it set faith above reason
+and preached the blind subjection of the one to the other; that was
+natural, seeing that our whole life on earth was held to be only a
+preparation for the legendary life beyond, and thus scientific research
+was robbed of any real value. The deliberate and successful attack on
+science began in the early part of the fourth century, particularly
+after the Council of Nicæa (327), presided over by Constantine--called
+the "Great" because he raised Christianity to the position of a state
+religion, and founded Constantinople, though a worthless character,
+a false-hearted hypocrite, and a murderer. The success of the papacy
+in its conflict with independent scientific thought and inquiry is
+best seen in the distressing condition of science and its literature
+during the Middle Ages. Not only were the rich literary treasures
+that classical antiquity had bequeathed to the world destroyed for
+the most part, or withdrawn from circulation, but the rack and the
+stake insured the silence of every heretic--that is, every independent
+thinker. If he did not keep his thoughts to himself, he had to look
+forward to being burned alive, as was the fate of the great monistic
+philosopher, Giordano Bruno, the reformer, John Huss, and more than a
+hundred thousand other "witnesses to the truth." The history of science
+in the Middle Ages teaches us on every page that independent thought
+and empirical research were completely buried for twelve sad centuries
+under the oppression of the omnipotent papacy.
+
+All that we esteem in true Christianity, in the sense of its founder
+and of his noblest followers, and that we must endeavor to save from
+the inevitable wreck of this great world religion for our new monistic
+religion, lies on its ethical and social planes. The principles of
+true humanism, the golden rule, the spirit of tolerance, the love
+of man, in the best and highest sense of the word--all these true
+graces of Christianity were not, indeed, first discovered and given
+to the world by that religion, but were successfully developed in the
+critical period when classical antiquity was hastening to its doom.
+The papacy, however, has attempted to convert all those virtues into
+the direct contrary, and still to hang out the sign of the old firm.
+Instead of Christian charity, it introduced a fanatical hatred of the
+followers of all other religions; with fire and sword it has pursued,
+not only the heathen, but every Christian sect that dared resist the
+imposition of ultramontane dogma. Tribunals for heretics were erected
+all over Europe, yielding unnumbered victims, whose torments seemed
+only to fill their persecutors, with all their Christian charity, with
+a peculiar satisfaction. The power of Rome was directed mercilessly
+for centuries against everything that stood in its way. Under the
+notorious Torquemada (1481-98), in Spain alone eight thousand heretics
+were burned alive and ninety thousand punished with the confiscation
+of their goods and the most grievous ecclesiastical fines; in the
+Netherlands, under the rule of Charles V., at least fifty thousand
+men fell victims to the clerical bloodthirst. And while the heavens
+resounded with the cry of the martyrs, the wealth of half the world was
+pouring into Rome, to which the whole of Christianity paid tribute, and
+the self-styled representatives of God on earth and their accomplices
+(not infrequently Atheists themselves) wallowed in pleasure and vice
+of every description. "And all these privileges," said the frivolous,
+syphilitic Pope, Leo X., "have been secured to us by the fable of Jesus
+Christ."
+
+Yet, with all the discipline of the Church and the fear of God, the
+condition of European society was pitiable. Feudalism, serfdom, the
+grace of God, and the favor of the monks ruled the land; the poor
+helots were only too glad to be permitted to raise their miserable
+huts under the shadow of the castle or the cloister, their secular and
+spiritual oppressors and exploiters. Even to-day we suffer from the
+aftermath of these awful ages and conditions, in which there was no
+question of care for science or higher mental culture save in rare
+circumstances and in secret. Ignorance, poverty, and superstition
+combined with the immoral operation of the law of celibacy, which
+had been introduced in the eleventh century, to consolidate the
+ever-growing power of the papacy. It has been calculated that there
+were more than ten million victims of fanatical religious hatred during
+this "Golden Age" of papal domination; and how many more million human
+victims must be put to the account of celibacy, oral confession, and
+moral constraint, the most pernicious and accursed institutions of
+the papal despotism! Unbelieving philosophers, who have collected
+disproofs of the existence of God, have overlooked one of the strongest
+arguments in that sense--the fact that the Roman "Vicar of Christ"
+could for twelve centuries perpetrate with impunity the most shameful
+and horrible deeds "in the name of God."
+
+
+III.--THE REFORMATION
+
+The history of civilization, which we are so fond of calling "the
+history of the world," enters upon its third period with the
+Reformation of the Christian Church, just as its second period begins
+with the founding of Christianity. With the Reformation begins the
+new birth of fettered reason, the reawakening of science, which the
+iron hand of the Christian papacy had relentlessly crushed for twelve
+hundred years. At the same time the spread of general education had
+already commenced, owing to the invention of printing about the
+middle of the fifteenth century; and towards its close several great
+events occurred, especially the discovery of America in 1492, which
+prepared the way for the "renaissance" of science in company with
+that of art. Indeed, certain very important advances were made in the
+knowledge of nature during the first half of the sixteenth century,
+which shook the prevailing system to its very foundations. Such were
+the circumnavigation of the globe by Magellan in 1522, which afforded
+empirical proof of its rotundity, and the founding of the new system of
+the world by Copernicus in 1543.
+
+Yet the 31st of October in the year 1517, the day on which Martin
+Luther nailed his ninety-five theses to the wooden door of Wittenburg
+Cathedral, must be regarded as the commencement of a new epoch; for
+on that day was forced the iron door of the prison in which the Papal
+Church had detained fettered reason for twelve hundred years. The
+merits of the great reformer have been partly exaggerated, partly
+underestimated. It has been justly pointed out that Luther, like all
+the other reformers, remained in manifold subjection to the deepest
+superstition. Thus he was throughout life a supporter of the rigid
+dogma of the verbal inspiration of the Bible; he zealously maintained
+the doctrines of the resurrection, original sin, predestination,
+justification by faith, etc. He rejected as folly the great discovery
+of Copernicus, because in the Bible "Joshua bade the sun, not the
+earth, stand still." He utterly failed to appreciate the great
+political revolutions of his time, especially the profound and just
+agitation of the peasantry. Worse still was the fanatical Calvin, of
+Geneva, who had the talented Spanish physician, Serveto, burned alive
+in 1553, because he rejected the absurd dogma of the Trinity. The
+fanatical "true believers" of the reformed Church followed only too
+frequently in the blood-stained footsteps of their papal enemies; as
+they do even in our own day. Deeds of unparalleled cruelty followed
+in the train of the Reformation--the massacre of St. Bartholomew and
+the persecution of the Huguenots in France, bloody heretic-hunts in
+Italy, civil war in England, and the Thirty Years War in Germany. Yet,
+in spite of those grave blemishes, to the sixteenth and seventeenth
+centuries belongs the honor of once more opening a free path to the
+thoughtful mind, and delivering reason from the oppressive yoke of the
+papacy. Thus only was made possible that great development of different
+tendencies in critical philosophy and of new paths in science which
+won for the subsequent eighteenth century the honorable title of "the
+century of enlightenment."
+
+
+IV.--THE PSEUDO-CHRISTIANITY OF THE NINETEENTH CENTURY
+
+As the fourth and last stage in the history of Christianity we oppose
+our nineteenth century to all its predecessors. It is true that the
+enlightenment of preceding centuries had promoted critical thought in
+every direction, and the rise of science itself had furnished powerful
+empirical weapons; yet it seems to us that our progress along both
+lines has been quite phenomenal during the nineteenth century. It
+has inaugurated an entirely new period in the history of the human
+mind, characterized by the development of the monistic philosophy
+of nature. At its very commencement the foundations were laid of a
+new anthropology (by the comparative anatomy of Cuvier) and of a new
+biology (by the _Philosophie Zoologique_ of Lamarck). The two great
+French scientists were quickly succeeded by two contemporary German
+scholars--Baer, the founder of the science of evolution, and Johannes
+Müller, the founder of comparative morphology and physiology. A
+pupil of Müller, Theodor Schwann, created the far-reaching cellular
+theory in 1838, in conjunction with M. Schleiden. Lyell had already
+traced the evolution of the earth to natural causes, and thus proved
+the application to our planet of the mechanical cosmogony which Kant
+had sketched with so much insight in 1755. Finally, Robert Mayer and
+Helmholtz established the principle of energy in 1842--the second,
+complementary half of the great law of substance, the first half of
+which (the persistence of matter) had been previously discovered by
+Lavoisier. Forty years ago Charles Darwin crowned all these profound
+revelations of the intimate nature of the universe by his new theory
+of evolution, the greatest natural-philosophical achievement of our
+century.
+
+What is the relation of modern Christianity to this vast and
+unparalleled progress of science? In the first place, the deep gulf
+between its two great branches, conservative Romanism and progressive
+Protestantism, has naturally widened. The ultramontane clergy (and
+we must associate with them the orthodox "evangelical alliance") had
+naturally to offer a strenuous opposition to this rapid advance of
+the emancipated mind; they continued unmoved in their rigid literal
+belief, demanding the unconditional surrender of reason to dogma.
+Liberal Protestantism, on the other hand, took refuge in a kind of
+monistic pantheism, and sought a means of reconciling two contradictory
+principles. It endeavored to combine the unavoidable recognition of
+the established laws of nature, and the philosophic conclusions that
+followed from them, with a purified form of religion, in which scarcely
+anything remained of the distinctive teaching of faith. There were
+many attempts at compromise to be found between the two extremes; but
+the conviction rapidly spread that dogmatic Christianity had lost every
+foundation, and that only its valuable ethical contents should be saved
+for the new monistic religion of the twentieth century. As, however,
+the existing external forms of the dominant Christian religion remained
+unaltered, and as, in spite of a progressive political development,
+they are more intimately than ever connected with the practical needs
+of the State, there has arisen that widespread religious profession
+in educated spheres which we can only call "pseudo-Christianity"--at
+the bottom it is a "religious lie" of the worst character. The great
+dangers which attend this conflict between sincere conviction and the
+hypocritical profession of modern pseudo-Christians are admirably
+described in Max Nordau's interesting work on _The Conventional Lies of
+Civilization_.
+
+In the midst of this obvious falseness of prevalent pseudo-Christianity
+there is one favorable circumstance for the progress of a rational
+study of nature: its most powerful and bitterest enemy, the Roman
+Church, threw off its mask of ostensible concern for higher mental
+development about the middle of the nineteenth century, and declared
+a _guerre à l'outrance_ against independent science. This happened
+in three important challenges to reason, for the explicitness and
+resoluteness of which modern science and culture cannot but be
+grateful to the "Vicar of Christ." (1) In December, 1854, the pope
+promulgated the dogma of the immaculate conception of Mary. (2) Ten
+years afterwards--in December, 1864--the pope published, in his
+famous _encyclica_, an absolute condemnation of the whole of modern
+civilization and culture; in the _syllabus_ that accompanied it he
+enumerated and anathematized all the rational theses and philosophical
+principles which are regarded by modern science as lucid truths. (3)
+Finally, six years afterwards--on July 13, 1870--the militant head of
+the Church crowned his folly by claiming _infallibility_ for himself
+and all his predecessors in the papal chair. This triumph of the Roman
+_curia_ was communicated to the astonished world five days afterwards,
+on the very day on which France declared war with Prussia. Two months
+later the temporal power of the pope was taken from him in consequence
+of the war.
+
+These three stupendous acts of the papacy were such obvious assaults on
+the reason of the nineteenth century that they gave rise, from the very
+beginning, to a most heated discussion even within orthodox Catholic
+circles. When the Vatican Council proceeded to define the dogma of
+infallibility on July 13, 1870, only three-fourths of the bishops
+declared in its favor, 451 out of 601 assenting; many other bishops,
+who wished to keep clear of the perilous definition, were absent from
+the council. But the shrewd pontiff had calculated better than the
+timid "discreet Catholics": even this extraordinary dogma was blindly
+accepted by the credulous and uneducated masses of the faithful.
+
+The whole history of the papacy, as it is substantiated by a thousand
+reliable sources and accessible documents, appears to the impartial
+student as an unscrupulous tissue of lying and deceit, a reckless
+pursuit of absolute mental despotism and secular power, a frivolous
+contradiction of all the high moral precepts which true Christianity
+enunciates--charity and toleration, truth and chastity, poverty and
+self-denial. When we judge the long series of popes and of the Roman
+princes of the Church, from whom the pope is chosen, by the standard of
+pure Christian morality, it is clear that the great majority of them
+were pitiful impostors, many of them utterly worthless and vicious.
+These well-known historical facts, however, do not prevent millions
+of educated Catholics from admitting the infallibility which the pope
+has claimed for himself; they do not prevent Protestant princes from
+going to Rome, and doing reverence to the pontiff (their most dangerous
+enemy); they do not prevent the fate of the German people from being
+intrusted to-day to the hands of the servants and followers of this
+"pious impostor" in the Reichstag--thanks to the incredible political
+indolence and credulity of the nation.
+
+The most interesting of the three great events by which the papacy has
+endeavored to maintain and strengthen its despotism in the nineteenth
+century is the publication of the encyclica and the syllabus in
+December, 1864. In these remarkable documents all independent action
+was forbidden to reason and science, and they were commanded to submit
+implicitly to faith--that is, to the decrees of the infallible pope.
+The great excitement which followed this sublime piece of effrontery in
+educated and independent circles was in proportion with the stupendous
+contents of the encyclica. Draper has given us an excellent discussion
+of its educational and political significance in his _History of the
+Conflict between Science and Religion_.
+
+The dogma of the immaculate conception seems, perhaps, to be less
+audacious and significant than the encyclica and the dogma of the
+infallibility of the pope. Yet not only the Roman hierarchy, but
+even some of the orthodox Protestants (the Evangelical Alliance, for
+instance), attach great importance to this thesis. What is known
+as the "immaculate oath"--that is, the confirmation of faith by an
+oath taken on the immaculate conception of Mary--is still regarded by
+millions of Christians as a sacred obligation. Many believers take the
+dogma in a twofold application; they think that the mother of Mary was
+impregnated by the Holy Ghost as well as Mary herself. Comparative and
+critical theology has recently shown that this myth has no greater
+claim to originality than most of the other stories in the Christian
+mythology; it has been borrowed from older religions, especially
+Buddhism. Similar myths were widely circulated in India, Persia,
+Asia Minor, and Greece several centuries before the birth of Christ.
+Whenever a king's unwedded daughter, or some other maid of high degree,
+gave birth to a child, the father was always pronounced to be a god, or
+a demi-god; in the Christian case it was the Holy Ghost.
+
+The special endowments of mind or body which often distinguished these
+"children of love" above ordinary offspring were thus partly explained
+by "heredity." Distinguished "sons of God" of this kind were held in
+high esteem both in antiquity and during the Middle Ages, while the
+moral code of modern civilization reproaches them with their want of
+honorable parentage. This applies even more forcibly to "daughters of
+God," though the poor maidens are just as little to blame for their
+want of a father. For the rest, every one who is familiar with the
+beautiful mythology of classical antiquity knows that these sons and
+daughters of the Greek and Roman gods often approach nearest to the
+highest ideal of humanity. Recollect the large legitimate family, and
+the still more numerous illegitimate offspring, of Zeus.
+
+To return to the particular question of the impregnation of the Virgin
+Mary by the Holy Ghost, we are referred to the gospels for testimony
+to the fact. The only two evangelists who speak of it, Matthew and
+Luke, relate in harmony that the Jewish maiden Mary was betrothed to
+the carpenter Joseph, but became pregnant without his co-operation,
+and, indeed, "by the Holy Ghost." As we have already related, the
+four canonical gospels which are regarded as the only genuine ones
+by the Christian Church, and adopted as the foundation of faith,
+were deliberately chosen from a much larger number of gospels, the
+details of which contradict each other sometimes just as freely as the
+assertions of the four. The fathers of the Church enumerate from forty
+to fifty of these spurious or apocryphal gospels; some of them are
+written both in Greek and Latin--for instance, the gospel of James, of
+Thomas, of Nicodemus, and so forth. The details which these apocryphal
+gospels give of the life of Christ, especially with regard to his birth
+and childhood, have just as much (or, on the whole, just as little)
+claim to historical validity as the four canonical gospels.
+
+Now we find in one of these documents an historical statement,
+confirmed, moreover, in the _Sepher Toldoth Jeschua_, which probably
+furnishes the simple and natural solution of the "world-riddle" of the
+supernatural conception and birth of Christ. The author curtly gives us
+in one sentence the remarkable statement which contains this solution:
+"Josephus Pandera, the Roman officer of a Calabrian legion which was in
+Judæa, seduced Miriam of Bethlehem, and was the father of Jesus." Other
+details given about Miriam (the Hebrew name for Mary) are far from
+being to the credit of the "Queen of Heaven."
+
+Naturally, these historical details are carefully avoided by the
+official theologian, but they assort badly with the traditional myth,
+and lift the veil from its mystery in a very simple and natural
+fashion. That makes it the more incumbent on impartial research and
+pure reason to make a critical examination of these statements. It
+must be admitted that they have much more title to credence than all
+the other statements about the birth of Christ. When, on familiar
+principles of science, we put aside the notion of supernatural
+conception through an "overshadowing of the Most High" as a pure myth,
+there only remains the widely accepted version of modern rational
+theology--that Joseph, the Jewish carpenter, was the true father of
+Christ. But this assumption is explicitly contradicted by many texts
+of the gospels; Christ himself was convinced that he was a "Son of
+God," and he never recognized his foster-father, Joseph, as his real
+parent. Joseph, indeed, wanted to leave his betrothed when he found her
+pregnant without his interference. He gave up this idea when an angel
+appeared to him in a dream and pacified him. As it is expressly stated
+in the first chapter of Matthew (vv. 24, 25), there was no sexual
+intercourse between Joseph and Mary until after Jesus was born.
+
+The statement of the apocryphal gospels, that the Roman officer,
+Pandera, was the true father of Christ, seems all the more credible
+when we make a careful anthropological study of the personality
+of Christ. He is generally regarded as purely Jewish. Yet the
+characteristics which distinguish his high and noble personality,
+and which give a distinct impress to his religion, are certainly not
+Semitical; they are rather features of the higher Arian race, and
+especially of its noblest branch, the Hellenes. Now, the name of
+Christ's real father, "Pandera," points unequivocally to a Greek
+origin; in one manuscript, in fact, it is written "Pandora." Pandora
+was, according to the Greek mythology, the first woman, born of
+the earth by Vulcan and adorned with every charm by the gods, who
+was espoused by Epimetheus, and sent by Zeus to men with the dread
+"Pandora-box," containing every evil, in punishment for the stealing of
+divine fire from heaven by Prometheus.
+
+And it is interesting to see the different reception that the
+love-story of Miriam has met with at the hands of the four great
+Christian nations of civilized Europe. The stern morality of the
+Teutonic races entirely repudiates it; the righteous German and the
+prudish Briton prefer to believe blindly in the impossible thesis of a
+conception "by the Holy Ghost." It is well known that this strenuous
+and carefully paraded prudery of the higher classes (especially in
+England) is by no means reflected in the true condition of sexual
+morality in high quarters. The revelations which the _Pall Mall
+Gazette_, for instance, made on the subject twelve years ago vividly
+recalled the condition of Babylon.
+
+The Romantic races, which ridicule this prudery and take sexual
+relations less seriously, find _Mary's Romance_ attractive enough;
+the special cult which "Our Lady" enjoys in France and Italy is often
+associated with this love-story with curious naïveté. Thus, for
+example, Paul de Regla (Dr. Desjardin), author of _Jesus of Nazareth
+considered from a Scientific, Historical, and Social Standpoint_
+(1894), finds precisely in the illegitimate birth of Christ a special
+"title to the halo that irradiates his noble form."
+
+It seemed to me necessary to enter fully into this important question
+of the origin of Christ in the sense of impartial historical science,
+because the Church militant itself lays great emphasis on it, and
+because it regards the miraculous structure which has been founded
+on it as one of its strongest weapons against modern thought. The
+highest ethical value of pure primitive Christianity and the ennobling
+influence of this "religion of love" on the history of civilization are
+quite independent of those mythical dogmas. The so-called "revelations"
+on which these myths are based are incompatible with the firmest
+results of modern science.
+
+
+
+
+CHAPTER XVIII
+
+OUR MONISTIC RELIGION
+
+    Monism as a Connecting Link between Religion and Science--The
+    _Cultur-Kampf_--The Relations of Church and State--Principles
+    of the Monistic Religion--Its Three-fold Ideal: the Good, the
+    True, and the Beautiful--Contradiction between Scientific and
+    Christian Truth--Harmony of the Monistic and the Christian Idea
+    of Virtue--Opposition between Monistic and Christian Views
+    of Art--Modern Expansion and Enrichment of Our Idea of the
+    World--Landscape-Painting and the Modern Enjoyment of Nature--The
+    Beauties of Nature--This World and Beyond--Monistic Churches
+
+
+Many distinguished scientists and philosophers of the day, who share
+our monistic views, consider that religion is generally played out.
+Their meaning is that the clear insight into the evolution of the world
+which the great scientific progress of the nineteenth century has
+afforded us will satisfy, not only the causal feeling of our reason,
+but even our highest emotional cravings. This view is correct in the
+sense that the two ideas, religion and science, would indeed blend
+into one if we had a perfectly clear and consecutive system of monism.
+However, there are but a few resolute thinkers who attain to this most
+pure and lofty conception of Spinoza and Goethe. Most of the educated
+people of our time (as distinct from the uncultured masses) remain in
+the conviction that religion is a separate branch of our mental life,
+independent of science, and not less valuable and indispensable.
+
+If we adopt this view, we can find a means of reconciling the two
+great and apparently quite distinct branches in the idea I put forward
+in "Monism, as a Connecting-Link between Religion and Science,"
+in 1892. In the preface to this _Confession of Faith of a Man of
+Science_ I expressed myself in the following words with regard to
+its double object: "In the first place, I must give expression to
+the rational system which is logically forced upon us by the recent
+progress of science; it dwells in the intimate thoughts of nearly every
+impartial and thoughtful scientist, though few have the courage or
+the disposition to avow it. In the second place, I would make of it a
+connecting-link between religion and science, and thus do away with
+the antithesis which has been needlessly maintained between these two
+branches of the highest activity of the human mind. The ethical craving
+of our emotion is satisfied by monism no less than the logical demand
+for causality on the part of reason."
+
+The remarkable interest which the discourse enkindled is a proof that
+in this monistic profession of faith I expressed the feeling not only
+of many scientists, but of a large number of cultured men and women
+of very different circles. Not only was I rewarded by hundreds of
+sympathetic letters, but by a wide circulation of the printed address,
+of which six editions were required within six months. I had the more
+reason to be content with this unexpected success, as this "confession
+of faith" was originally merely an occasional speech which I delivered
+unprepared on October 9, 1892, at Altenburg, during the jubilee of the
+Scientific Society of East Germany. Naturally there was the usual
+demonstration on the other side; I was fiercely attacked, not only by
+the ultramontane press, the sworn defenders of superstition, but also
+by the "liberal" controversialists of evangelical Christianity, who
+profess to defend both scientific truth and purified faith. In the
+seven years that have ensued since that time the great struggle between
+modern science and orthodox Christianity has become more threatening;
+it has grown more dangerous for science in proportion as Christianity
+has found support in an increasing mental and political reaction. In
+some countries the Church has made such progress that the freedom
+of thought and conscience, which is guaranteed by the laws, is in
+practice gravely menaced (for instance, in Bavaria). The great historic
+struggle which Draper has so admirably depicted in his _Conflict
+between Religion and Science_ is to-day more acute and significant than
+ever. For the last twenty-seven years it has been rightly called the
+"_cultur-kampf_."
+
+The famous encyclica and syllabus which the militant pope, Pius IX.,
+sent out into the entire world in 1864 were a declaration of war on
+the whole of modern science; they demanded the blind submission of
+reason to the dogmas of the infallible pope. The enormity of this
+crude assault on the highest treasures of civilization even roused
+many indolent minds from the slumber of belief. Together with the
+subsequent promulgation of the papal infallibility (1870), the
+encyclica provoked a deep wave of irritation and an energetic repulse
+which held out high hopes. In the new German empire, which had attained
+its indispensable national unity by the heavy sacrifices of the wars
+of 1866 and 1871, the insolent attacks of the pope were felt to be
+particularly offensive. On the one hand, Germany is the cradle of
+the Reformation and the modern emancipation of reason; on the other
+hand, it unfortunately has in its 18,000,000 Catholics a vast host of
+militant believers, who are unsurpassed by any other civilized people
+in blind obedience to their chief shepherd.
+
+The dangers of such a situation were clearly recognized by the
+great statesman who had solved the political "world-riddle" of the
+dismemberment of Germany, and had led us by a marvellous statecraft
+to the long-desired goal of national unity and power. Prince Bismarck
+began the famous struggle with the Vatican, which is known as the
+_cultur-kampf_, in 1872, and it was conducted with equal ability and
+energy by the distinguished Minister of Worship, Falk, author of the
+May laws of 1873. Unfortunately, Bismarck had to desist six years
+afterwards. Although the great statesman was a remarkable judge of men
+and a realistic politician of immense tact, he had underestimated the
+force of three powerful obstacles--first, the unsurpassed cunning and
+unscrupulous treachery of the Roman _curia_; secondly, the correlative
+ingratitude and credulity of the uneducated Catholic masses, on which
+the papacy built; and, thirdly, the power of apathy, the continuance
+of the irrational, simply because it is in possession. Hence, in 1878,
+when the abler Leo XIII. had ascended the pontifical throne, the fatal
+"To Canossa" was heard once more. From that time the newly established
+power of Rome grew in strength; partly through the unscrupulous
+intrigues and serpentine bends of its slippery Jesuitical politics,
+partly through the false Church-politics of the German government and
+the marvellous political incompetence of the German people. We have,
+therefore, at the close of the nineteenth century to endure the
+pitiful spectacle of the Catholic "Centre" being the most important
+section of the Reichstag, and the fate of our humiliated country
+depending on a papal party, which does not constitute numerically a
+third part of the nation.
+
+When the _cultur-kampf_ began in 1872, it was justly acclaimed by
+all independent thinkers as a political renewal of the Reformation,
+a vigorous attempt to free modern civilization from the yoke of
+papal despotism. The whole of the Liberal press hailed Bismarck as a
+"political Luther"--as the great hero, not only of the national unity,
+but also of the rational emancipation of Germany. Ten years afterwards,
+when the papacy had proved victorious, the same "Liberal press" changed
+its colors, and denounced the _cultur-kampf_ as a great mistake; and
+it does the same thing to-day. The facts show how short is the memory
+of our journalists, how defective their knowledge of history, and how
+poor their philosophic education. The so-called "Peace between Church
+and State" is never more than a suspension of hostilities. The modern
+papacy, true to the despotic principles it has followed for the last
+sixteen hundred years, is determined to wield sole dominion over the
+credulous souls of men; it must demand the absolute submission of
+the cultured State, which, as such, defends the rights of reason and
+science. True and enduring peace there cannot be until one of the
+combatants lies powerless on the ground. Either the Church wins, and
+then farewell to all "free science and free teaching"--then are our
+universities no better than jails, and our colleges become cloistral
+schools; or else the modern rational State proves victorious--then,
+in the twentieth century, human culture, freedom, and prosperity will
+continue their progressive development until they far surpass even the
+height of the nineteenth century.
+
+In order to compass these high aims, it is of the first importance that
+modern science not only shatter the false structures of superstition
+and sweep their ruins from the path, but that it also erect a new
+abode for human emotion on the ground it has cleared--a "palace of
+reason," in which, under the influence of our new monistic views, we do
+reverence to the real trinity of the nineteenth century--the trinity of
+"the true, the good, and the beautiful." In order to give a tangible
+shape to the cult of this divine ideal, we must first of all compare
+our position with the dominant forms of Christianity, and realize
+the changes that are involved in the substitution of the one for the
+other. For, in spite of its errors and defects, the Christian religion
+(in its primitive and purer form) has so high an ethical value, and
+has entered so deeply into the most important social and political
+movements of civilized history for the last fifteen hundred years,
+that we must appeal as much as possible to its existing institutions
+in the establishment of our monistic religion. We do not seek a mighty
+_revolution_, but a rational _reformation_, of our religious life. And
+just as, two thousand years ago, the classic poetry of the ancient
+Greeks incarnated their ideals of virtue in divine shapes, so may
+we, too, lend the character of noble goddesses to our three rational
+ideals. We must inquire into the features of the three goddesses of the
+monist--truth, beauty, and virtue; and we must study their relation
+to the three corresponding ideals of Christianity which they are to
+replace.
+
+I. The preceding inquiries (especially those of the first and third
+sections) have convinced us that truth unadulterated is only to be
+found in the temple of the study of nature, and that the only available
+paths to it are critical observation and reflection--the empirical
+investigation of facts and the rational study of their efficient
+causes. In this way we arrive, by means of pure reason, at true
+science, the highest treasure of civilized man. We must, in accordance
+with the arguments of our sixteenth chapter, reject what is called
+"revelation," the poetry of faith, that affirms the discovery of truth
+in a supernatural fashion, without the assistance of reason. And since
+the entire structure of the Judæo-Christian religion, like that of the
+Mohammedan and the Buddhistic, rests on these so-called revelations,
+and these mystic fruits of the imagination directly contradict the
+clear results of empirical research, it is obvious that we shall
+only attain to a knowledge of the truth by the rational activity of
+genuine science, not by the poetic imagining of a mystic faith. In this
+respect it is quite certain that the Christian system must give way
+to the monistic. The goddess of truth dwells in the temple of nature,
+in the green woods, on the blue sea, and on the snowy summits of the
+hills--not in the gloom of the cloister, nor in the narrow prisons of
+our jail-like schools, nor in the clouds of incense of the Christian
+churches. The paths which lead to the noble divinity of truth and
+knowledge are the loving study of nature and its laws, the observation
+of the infinitely great star-world with the aid of the telescope, and
+the infinitely tiny cell-world with the aid of the microscope--not
+senseless ceremonies and unthinking prayers, not alms and Peter's
+Pence. The rich gifts which the goddess of truth bestows on us are the
+noble fruits of the tree of knowledge and the inestimable treasure of a
+clear, unified view of the world--not belief in supernatural miracles
+and the illusion of an eternal life.
+
+II. It is otherwise with the divine ideal of eternal goodness. In our
+search for the truth we have entirely to exclude the "revelation" of
+the churches, and devote ourselves solely to the study of nature; but,
+on the other hand, the idea of the good, which we call virtue, in
+our monistic religion coincides for the most part with the Christian
+idea of virtue. We are speaking, naturally, of the primitive and
+pure Christianity of the first three centuries, as far as we learn
+its moral teaching from the gospels and the epistles of Paul; it
+does not apply to the Vatican caricature of that pure doctrine which
+has dominated European civilization, to its infinite prejudice, for
+twelve hundred years. The best part of Christian morality, to which we
+firmly adhere, is represented by the humanist precepts of charity and
+toleration, compassion and assistance. However, these noble commands,
+which are set down as "Christian" morality (in its best sense), are by
+no means original discoveries of Christianity; they are derived from
+earlier religions. The Golden Rule, which sums up these precepts in
+one sentence, is centuries older than Christianity. In the conduct of
+life this law of natural morality has been followed just as frequently
+by non-Christians and atheists as it has been neglected by pious
+believers. Moreover, Christian ethics was marred by the great defect
+of a narrow insistence on altruism and a denunciation of egoism. Our
+monistic ethics lays equal emphasis on the two, and finds perfect
+virtue in the just balance of love of self and love of one's neighbor
+(cf. chap. xix.).
+
+III. But monism enters into its strongest opposition to Christianity
+on the question of beauty. Primitive Christianity preached the
+worthlessness of earthly life, regarding it merely as a preparation
+for an eternal life beyond. Hence it immediately followed that all we
+find in the life of man here below, all that is beautiful in art and
+science, in public and in private life, is of no real value. The true
+Christian must avert his eyes from them; he must think only of a worthy
+preparation for the life beyond. Contempt of nature, aversion from all
+its inexhaustible charms, rejection of every kind of fine art, are
+Christian duties; and they are carried out to perfection when a man
+separates himself from his fellows, chastises his body, and spends all
+his time in prayer in the cloister or the hermit's cell.
+
+History teaches us that this ascetical morality that would scorn the
+whole of nature had, as a natural consequence, the very opposite effect
+to that it intended. Monasteries, the homes of chastity and discipline,
+soon became dens of the wildest orgies; the sexual commerce of monks
+and nuns has inspired shoals of novels, as it is so faithfully depicted
+in the literature of the Renaissance. The cult of the "beautiful,"
+which was then practised, was in flagrant contradiction with the
+vaunted "abandonment of the world"; and the same must be said of the
+pomp and luxury which soon developed in the immoral private lives of
+the higher ecclesiastics and in the artistic decoration of Christian
+churches and monasteries.
+
+It may be objected that our view is refuted by the splendor of
+Christian art, which, especially in the best days of the Middle Ages,
+created works of undying beauty. The graceful Gothic cathedrals and
+Byzantine basilicas, the hundreds of magnificent chapels, the thousands
+of marble statues of saints and martyrs, the millions of fine pictures
+of saints, of profoundly conceived representations of Christ and the
+madonna--all are proofs of the development of a noble art in the Middle
+Ages, which is unique of its kind. All these splendid monuments of
+mediæval art are untouched in their high æsthetic value, whatever we
+say of their mixture of truth and fancy. Yes; but what has all that
+to do with the pure teaching of Christianity--with that religion of
+sacrifice that turned scornfully away from all earthly parade and
+glamour, from all material beauty and art; that made light of the life
+of the family and the love of woman; that urged an exclusive concern as
+to the immaterial goods of eternal life? The idea of a Christian art
+is a contradiction in terms--a _contradictio in adjecto_. The wealthy
+princes of the Church who fostered it were candidly aiming at very
+different ideals, and they completely attained them. In directing the
+whole interest and activity of the human mind in the Middle Ages to the
+Christian Church and its distinctive art they were diverting it _from
+nature_ and from the knowledge of the treasures that were hidden in it,
+and would have conducted to independent science. Moreover, the daily
+sight of the huge images of the saints and of the scenes of "sacred
+history" continually reminded the faithful of the vast collection of
+myths that the Church had made. The legends themselves were taught
+and believed to be true narratives, and the stories of miracles to be
+records of actual events. It cannot be doubted that in this respect
+Christian art has exercised an immense influence on general culture,
+and especially in the strengthening of Christian belief--an influence
+which still endures throughout the entire civilized world.
+
+The diametrical opposite of this dominant Christian art is the new
+artistic tendency which has been developed during the present century
+in connection with science. The remarkable expansion of our knowledge
+of nature, and the discovery of countless beautiful forms of life,
+which it includes, have awakened quite a new æsthetic sense in our
+generation, and thus given a new tone to painting and sculpture.
+Numerous scientific voyages and expeditions for the exploration
+of unknown lands and seas, partly in earlier centuries, but more
+especially in the nineteenth, have brought to light an undreamed
+abundance of new organic forms. The number of new species of animals
+and plants soon became enormous, and among them (especially among the
+lower groups that had been neglected before) there were thousands
+of forms of great beauty and interest, affording an entirely new
+inspiration for painting, sculpture, architecture, and technical
+art. In this respect a new world was revealed by the great advance
+of microscopic research in the second half of the century, and
+especially by the discovery of the marvellous inhabitants of the
+deep sea, which were first brought to light by the famous expedition
+of the _Challenger_ (1872-76). Thousands of graceful radiolaria and
+thalamophora, of pretty medusæ and corals, of extraordinary molluscs,
+and crabs, suddenly introduced us to a wealth of hidden organisms
+beyond all anticipation, the peculiar beauty and diversity of which
+far transcend all the creations of the human imagination. In the
+fifty large volumes of the account of the _Challenger_ expedition a
+vast number of these beautiful forms are delineated on three thousand
+plates; and there are millions of other lovely organisms described in
+other great works that are included in the fast-growing literature of
+zoology and botany of the last ten years. I began on a small scale to
+select a number of these beautiful forms for more popular description
+in my _Art Forms in Nature_ (1899).
+
+However, there is now no need for long voyages and costly works to
+appreciate the beauties of this world. A man needs only to keep his
+eyes open and his mind disciplined. Surrounding nature offers us
+everywhere a marvellous wealth of lovely and interesting objects of all
+kinds. In every bit of moss and blade of grass, in every beetle and
+butterfly, we find, when we examine it carefully, beauties which are
+usually overlooked. Above all, when we examine them with a powerful
+glass or, better still, with a good microscope, we find everywhere in
+nature a new world of inexhaustible charms.
+
+But the nineteenth century has not only opened our eyes to the æsthetic
+enjoyment of the microscopic world; it has shown us the beauty of
+the greater objects in nature. Even at its commencement it was the
+fashion to regard the mountains as magnificent but forbidding, and
+the sea as sublime but dreaded. At its close the majority of educated
+people--especially they who dwell in the great cities--are delighted
+to enjoy the glories of the Alps and the crystal splendor of the
+glacier world for a fortnight every year, or to drink in the majesty
+of the ocean and the lovely scenery of its coasts. All these sources
+of the keenest enjoyment of nature have only recently been revealed
+to us in all their splendor, and the remarkable progress we have
+made in facility and rapidity of conveyance has given even the less
+wealthy an opportunity of approaching them. All this progress in the
+æsthetic enjoyment of nature--and, proportionately, in the scientific
+understanding of nature--implies an equal advance in higher mental
+development and, consequently, in the direction of our monistic
+religion.
+
+The opposite character of our _naturalistic_ century to that of the
+_anthropistic_ centuries that preceded is especially noticeable in
+the different appreciation and spread of illustrations of the most
+diverse natural objects. In our own days a lively interest in artistic
+work of that kind has been developed, which did not exist in earlier
+ages; it has been supported by the remarkable progress of commerce
+and technical art which have facilitated a wide popularization of
+such illustrations. Countless illustrated periodicals convey along
+with their general information a sense of the inexhaustible beauty of
+nature in all its departments. In particular, landscape-painting has
+acquired an importance that surpassed all imagination. In the first
+half of the century one of our greatest and most erudite scientists,
+Alexander Humboldt, had pointed out that the development of modern
+landscape-painting is not only of great importance as an incentive
+to the study of nature and as a means of geographical description,
+but that it is to be commended in other respects as a noble educative
+medium. Since that time the taste for it has considerably increased.
+It should be the aim at every school to teach the children to enjoy
+scenery at an early age, and to give them the valuable art of
+imprinting on the memory by a drawing or water-color sketch.
+
+The infinite wealth of nature in what is beautiful and sublime offers
+every man with open eyes and an æsthetic sense an incalculable sum of
+choicest gifts. Still, however valuable and agreeable is the immediate
+enjoyment of each single gift, its worth is doubled by a knowledge of
+its meaning and its connection with the rest of nature. When Humboldt
+gave us the "outline of a physical description of the world" in his
+magnificent _Cosmos_ forty years ago, and when he combined scientific
+and æsthetic consideration so happily in his standard _Prospects of
+Nature_, he justly indicated how closely the higher enjoyment of nature
+is connected with the "scientific establishment of cosmic laws," and
+that the conjunction of the two serves to raise human nature to a
+higher stage of perfection. The astonishment with which we gaze upon
+the starry heavens and the microscopic life in a drop of water, the awe
+with which we trace the marvellous working of energy in the motion of
+matter, the reverence with which we grasp the universal dominance of
+the law of substance throughout the universe--all these are part of our
+emotional life, falling under the heading of "natural religion."
+
+This progress of modern times in knowledge of the true and enjoyment
+of the beautiful expresses, on the one hand, a valuable element of our
+monistic religion, but is, on the other hand, in fatal opposition to
+Christianity. For the human mind is thus made to live on this side of
+the grave; Christianity would have it ever gaze beyond. Monism teaches
+that we are perishable children of the earth, who for one or two,
+or, at the most, three generations, have the good fortune to enjoy
+the treasures of our planet, to drink of the inexhaustible fountain
+of its beauty, and to trace out the marvellous play of its forces.
+Christianity would teach us that the earth is "a vale of tears," in
+which we have but a brief period to chasten and torment ourselves in
+order to merit the life of eternal bliss beyond. Where this "beyond"
+is, and of what joys the glory of this eternal life is compacted, no
+revelation has ever told us. As long as "heaven" was thought to be the
+blue vault that hovers over the disk of our planet, and is illumined
+by the twinkling light of a few thousand stars, the human imagination
+could picture to itself the ambrosial banquets of the Olympic gods
+above or the laden tables of the happy dwellers in Valhalla. But now
+all these deities and the immortal souls that sat at their tables are
+"houseless and homeless," as David Strauss has so ably described; for
+we know from astrophysical science that the immeasurable depths of
+space are filled with a prosaic ether, and that millions of heavenly
+bodies, ruled by eternal laws of iron, rush hither and thither in the
+great ocean, in their eternal rhythm of life and death.
+
+The places of devotion, in which men seek the satisfaction of their
+religious emotions and worship the objects of their reverence, are
+regarded as sacred "churches." The pagodas of Buddhistic Asia, the
+Greek temples of classical antiquity, the synagogues of Palestine,
+the mosques of Egypt, the Catholic cathedrals of the south, and the
+Protestant cathedrals of the north, of Europe--all these "houses of
+God" serve to raise man above the misery and the prose of daily life,
+to lift him into the sacred, poetic atmosphere of a higher, ideal
+world. They attain this end in a thousand different ways, according
+to their various forms of worship and their age. The modern man who
+"has science and art"--and, therefore, "religion"--needs no special
+church, no narrow, enclosed portion of space. For through the length
+and breadth of free nature, wherever he turns his gaze, to the whole
+universe or to any single part of it, he finds, indeed, the grim
+"struggle for life," but by its side are ever "the good, the true, and
+the beautiful"; his church is commensurate with the whole of glorious
+nature. Still, there will always be men of special temperament who will
+desire to have decorated temples or churches as places of devotion
+to which they may withdraw. Just as the Catholics had to relinquish a
+number of churches to the Reformation in the sixteenth century, so a
+still larger number will pass over to "free societies" of monists in
+the coming years.
+
+
+
+
+CHAPTER XIX
+
+OUR MONISTIC ETHICS
+
+    Monistic and Dualistic Ethics--Contradiction of Pure and
+    Practical Reason in Kant--His Categorical Imperative--The
+    Neo-Kantians--Herbert Spencer--Egoism and Altruism--Equivalence
+    of the Two Instincts--The Fundamental Law of Ethics: the Golden
+    Rule--Its Antiquity--Christian Ethics--Contempt of Self, the
+    Body, Nature, Civilization, the Family, Woman--Roman Catholic
+    Ethics--Immoral Results of Celibacy--Necessity for the Abolition of
+    the Law of Celibacy, Oral Confession, and Indulgences--State and
+    Church--Religion a Private Concern--Church and School--State and
+    School--Need of School Reform
+
+
+The practical conduct of life makes a number of definite ethical claims
+on a man which can only be duly and naturally satisfied when they are
+in complete harmony with his view of the world. In accordance with this
+fundamental principle of our monistic philosophy, our whole system of
+ethics must be rationally connected with the unified conception of the
+cosmos which we have formed by our advanced knowledge of the laws of
+nature. Just as the infinite universe is one great whole in the light
+of our monistic teaching, so the spiritual and moral life of man is
+a part of this cosmos, and our naturalistic ordering of it must also
+be monistic. There are not two different, separate worlds--the one
+physical and material, and the other moral and immaterial.
+
+The great majority of philosophers and theologians still hold the
+contrary opinion. They affirm, with Kant, that the moral world is quite
+independent of the physical, and is subject to very different laws;
+hence a man's conscience, as the basis of his moral life, must also be
+quite independent of our scientific knowledge of the world, and must be
+based rather on his religious faith. On that theory the study of the
+moral world belongs to _practical_ reason, while that of nature, or of
+the physical world, is referred to _pure_ or theoretical reason. This
+unequivocal and conscious dualism of Kant's philosophy was its greatest
+defect; it has caused, and still causes, incalculable mischief. First
+of all the "critical Kant" had built up the splendid and marvellous
+palace of pure reason, and convincingly proved that the three great
+central dogmas of metaphysics--a personal God, free will, and the
+immortal soul--had no place whatever in it, and that no rational proof
+could be found of their reality. Afterwards, however, the "dogmatic
+Kant" superimposed on this true crystal palace of _pure_ reason the
+glittering, ideal castle in the air of _practical_ reason, in which
+three imposing church-naves were designed for the accommodation of
+those three great mystic divinities. When they had been put out at the
+front door by rational knowledge they returned by the back door under
+the guidance of irrational faith.
+
+The cupola of his great cathedral of faith was crowned by Kant with his
+curious idol, the famous "categorical imperative." According to it,
+the demand of the universal moral law is unconditional, independent of
+any regard to actuality or potentiality. It runs: "Act at all times in
+such wise that the maxim (or the subjective law of thy will) may hold
+good as a principle of a universal law." On that theory all normal men
+would have the same sense of duty. Modern anthropology has ruthlessly
+dissipated that pretty dream; it has shown that conceptions of duty
+differ even more among uncivilized than among civilized nations. All
+the actions and customs which we regard as sins or loathsome crimes
+(theft, fraud, murder, adultery, etc.) are considered by other nations
+in certain circumstances to be virtues, or even sacred duties.
+
+Although the obvious contradiction of the two forms of reason in Kant's
+teaching, the fundamental antagonism of pure and practical reason, was
+recognized and attacked at the very beginning of the century, it is
+still pretty widely accepted. The modern school of neo-Kantians urges a
+"return to Kant" so pressingly precisely on account of this agreeable
+dualism; the Church militant zealously supports it because it fits
+in admirably with its own mystic faith. But it met with an effective
+reverse at the hands of modern science in the second half of the
+nineteenth century, which entirely demolished the theses of the system
+of practical reason. Monistic cosmology proved, on the basis of the law
+of substance, that there is no personal God; comparative and genetic
+psychology showed that there cannot be an immortal soul; and monistic
+physiology proved the futility of the assumption of "free will."
+Finally, the science of evolution made it clear that the same eternal
+iron laws that rule in the inorganic world are valid too in the organic
+and moral world.
+
+But modern science gives not only a negative support to practical
+philosophy and ethics in demolishing the Kantian dualism, but it
+renders the positive service of substituting for it the new structure
+of ethical monism. It shows that the feeling of duty does not rest
+on an illusory "categorical imperative," but on the solid ground of
+_social instinct_, as we find in the case of all social animals. It
+regards as the highest aim of all morality the re-establishment of a
+sound harmony between egoism and altruism, between self-love and the
+love of one's neighbor. It is to the great English philosopher, Herbert
+Spencer, that we owe the founding of this monistic ethics on a basis of
+evolution.
+
+Man belongs to the social vertebrates, and has, therefore, like all
+social animals, two sets of duties--first to himself, and secondly
+to the society to which he belongs. The former are the behests of
+self-love or egoism, the latter of love for one's fellows or altruism.
+The two sets of precepts are equally just, equally natural, and equally
+indispensable. If a man desire to have the advantage of living in an
+organized community, he has to consult not only his own fortune, but
+also that of the society, and of the "neighbors" who form the society.
+He must realize that its prosperity is his own prosperity, and that it
+cannot suffer without his own injury. This fundamental law of society
+is so simple and so inevitable that one cannot understand how it can be
+contradicted in theory or in practice; yet that is done to-day, and has
+been done for thousands of years.
+
+The equal appreciation of these two natural impulses, or the moral
+equivalence of self-love and love of others, is the chief and the
+fundamental principle of our morality. Hence the highest aim of all
+ethics is very simple--it is the re-establishment of "the natural
+equality of egoism and altruism, of the love of one's self and the
+love of one's neighbor." The Golden Rule says: "Do unto others as you
+would that they should do unto you." From this highest precept of
+Christianity it follows of itself that we have just as sacred duties
+towards ourselves as we have towards our fellows. I have explained
+my conception of this principle in my _Monism_, and laid down three
+important theses. (1) Both these concurrent impulses are natural
+laws, of equal importance and necessity for the preservation of the
+family and the society; egoism secures the self-preservation of the
+individual, altruism that of the species which is made up of the chain
+of perishable individuals. (2) The social duties which are imposed
+by the social structure of the associated individuals, and by means
+of which it secures its preservation, are merely higher evolutionary
+stages of the social instincts, which we find in all higher social
+animals (as "habits which have become hereditary"). (3) In the case of
+civilized man all ethics, theoretical or practical, being "a science
+of rules," is connected with his view of the world at large, and
+consequently with his religion.
+
+From the recognition of the fundamental principle of our morality
+we may immediately deduce its highest precept, that noble command,
+which is often called the Golden Rule of morals, or, briefly, the
+Golden Rule. Christ repeatedly expressed it in the simple phrase:
+"Thou shalt love thy neighbor as thyself." Mark adds that "there is
+no greater commandment than this," and Matthew says: "In these two
+commandments is the whole law and the prophets." In this greatest and
+highest commandment our monistic ethics is completely at one with
+Christianity. We must, however, recall the historical fact that the
+formulation of this supreme command is not an original merit of Christ,
+as the majority of Christian theologians affirm and their uncritical
+supporters blindly accept. The Golden Rule is five hundred years
+older than Christ; it was laid down as the highest moral principle by
+many Greek and Oriental sages. Pittacus, of Mylene, one of the seven
+wise men of Greece, said six hundred and twenty years before Christ:
+"Do not that to thy neighbor that thou wouldst not suffer from him."
+Confucius, the great Chinese philosopher and religious founder (who
+rejected the idea of a personal God and of the immortality of the
+soul), said five hundred years B.C.: "Do to every man as thou wouldst
+have him do to thee; and do not to another what thou wouldst not have
+him do to thee. This precept only dost thou need; it is the foundation
+of all other commandments." Aristotle taught about the middle of the
+fourth century B.C.: "We must act towards others as we wish others
+to act towards us." In the same sense, and partly in the same words,
+the Golden Rule was given by Thales, Isocrates, Aristippus, Sextus,
+the Pythagorean, and other philosophers of classic antiquity--several
+centuries before Christ. From this collection it is clear that the
+Golden Rule had a _polyphyletic_ origin--that is, it was formulated by
+a number of philosophers at different times and in different places,
+quite independently of each other. Otherwise it must be assumed that
+Jesus derived it from some other Oriental source, from ancient Semitic,
+Indian, Chinese, or especially Buddhistic traditions, as has been
+proved in the case of most of the other Christian doctrines.
+
+As the great ethical principle is thus twenty-five hundred years old,
+and as Christianity itself has put it at the head of its moral teaching
+as the highest and all-embracing commandment, it follows that our
+monistic ethics is in complete harmony on this important point, not
+only with the ethics of the ancient heathens, but also with that of
+Christianity. Unfortunately this harmony is disturbed by the fact that
+the gospels and the Pauline epistles contain many other points of moral
+teaching, which contradict our first and supreme commandment. Christian
+theologians have fruitlessly striven to explain away these striking
+and painful contradictions by their ingenious interpretations. We need
+not enter into that question now, but we must briefly consider those
+unfortunate aspects of Christian ethics which are incompatible with the
+better thought of the modern age, and which are distinctly injurious
+in their practical consequences. Of that character is the contempt
+which Christianity has shown for self, for the body, for nature, for
+civilization, for the family, and for woman.
+
+I. The supreme mistake of Christian ethics, and one which runs
+directly counter to the Golden Rule, is its exaggeration of love of
+one's neighbor at the expense of self-love. Christianity attacks and
+despises egoism on principle. Yet that natural impulse is absolutely
+indispensable in view of self-preservation; indeed, one may say that
+even altruism, its apparent opposite, is only an enlightened egoism.
+Nothing great or elevated has ever taken place without egoism, and
+without the passion that urges us to great sacrifices. It is only
+the excesses of the impulse that are injurious. One of the Christian
+precepts that were impressed upon us in our early youth as of great
+importance, and that are glorified in millions of sermons, is: "Love
+your enemies, bless them that curse you, do good to them that hate you,
+and pray for them which despitefully use you and persecute you." It is
+a very ideal precept, but as useless in practice as it is unnatural.
+So it is with the counsel, "If any man will take away thy coat, let
+him have thy cloak also." Translated into the terms of modern life,
+that means: "When some unscrupulous scoundrel has defrauded thee of
+half thy goods, let him have the other half also." Or, again, in the
+language of modern politics: "When the pious English take from you
+simple Germans one after another of your new and valuable colonies in
+Africa, let them have all the rest of your colonies also--or, best of
+all, give them Germany itself." And, while we touch on the marvellous
+world-politics of modern England, we may note in passing its direct
+contradiction of every precept of Christian charity, which is more
+frequently on the lips of that great nation than of any other nation in
+the world. However, the glaring contradiction between the theoretical,
+_ideal_, altruistic morality of the human individual and the _real_,
+purely selfish morality of the human community, and especially of the
+civilized Christian state, is a familiar fact. It would be interesting
+to determine mathematically in what proportion among organized men the
+altruistic ethical ideal of the individual changes into its contrary,
+the purely egoistic "real politics" of the state and the nation.
+
+II. Since the Christian faith takes a wholly dualistic view of the
+human organism and attributes to the immortal soul only a temporary
+sojourn in the mortal frame, it very naturally sets a much greater
+value on the soul than on the body. Hence results that neglect of the
+care of the body, of training, and of cleanliness which contrasts the
+life of the Christian Middle Ages so unfavorably with that of pagan
+classical antiquity. Christian ethics contains none of those firm
+commands as to daily ablutions which are theoretically laid down and
+practically fulfilled in the Mohammedan, Hindoo, and other religions.
+In many monasteries the ideal of the pious Christian is the man who
+does not wash and clothe himself properly, who never changes his
+malodorous gown, and who, instead of regular work, fills up his useless
+life with mechanical prayers, senseless fasts, and so forth. As a
+special outgrowth of this contempt of the body we have the disgusting
+discipline of the flagellants and other ascetics.
+
+III. One source of countless theoretical errors and practical
+blemishes, of deplorable crudity and privation, is found in the false
+anthropism of Christianity--that is, in the unique position which
+it gives to man, as the image of God, in opposition to all the rest
+of nature. In this way it has contributed, not only to an extremely
+injurious isolation from our glorious mother "nature," but also to
+a regrettable contempt of all other organisms. Christianity has no
+place for that well-known love of animals, that sympathy with the
+nearly related and friendly mammals (dogs, horses, cattle, etc.),
+which is urged in the ethical teaching of many of the older religions,
+especially Buddhism. Whoever has spent much time in the south of Europe
+must have often witnessed those frightful sufferings of animals which
+fill us friends of animals with the deepest sympathy and indignation.
+And when one expostulates with these brutal "Christians" on their
+cruelty, the only answer is, with a laugh: "But the beasts are not
+Christians." Unfortunately Descartes gave some support to the error in
+teaching that man only has a sensitive soul, not the animal.
+
+How much more elevated is our monistic ethics than the Christian in
+this regard! Darwinism teaches us that we have descended immediately
+from the primates, and, in a secondary degree, from a long series
+of earlier mammals, and that, therefore, they are "our brothers";
+physiology informs us that they have the same nerves and sense-organs
+as we, and the same feelings of pleasure and pain. No sympathetic
+monistic scientist would ever be guilty of that brutal treatment of
+animals which comes so lightly to the Christian in his anthropistic
+illusion--to the "child of the God of love." Moreover, this Christian
+contempt of nature on principle deprives man of an abundance of the
+highest earthly joys, especially of the keen, ennobling enjoyment of
+nature.
+
+IV. Since, according to Christ's teaching, our planet is "a vale of
+tears," and our earthly life is valueless and a mere preparation for a
+better life to come, it has succeeded in inducing men to sacrifice all
+happiness on this side of eternity and make light of all earthly goods.
+Among these "earthly goods," in the case of the modern civilized man,
+we must include the countless great and small conveniences of technical
+science, hygiene, commerce, etc., which have made modern life cheerful
+and comfortable; we must include all the gratifications of painting,
+sculpture, music, and poetry, which flourished exceedingly even during
+the Middle Ages (in spite of its principles), and which we esteem
+as "ideal pleasures"; we must include all that invaluable progress
+of science, especially the study of nature, of which the nineteenth
+century is justly proud. All these "earthly goods," that have so high a
+value in the eyes of the monist, are worthless--nay, injurious--for the
+most part, according to Christian teaching; the stern code of Christian
+morals should look just as unfavorably on the pursuit of these
+pleasures as our humanistic ethics fosters and encourages it. Once
+more, therefore, Christianity is found to be an enemy to civilization,
+and the struggle which modern thought and science are compelled to
+conduct with it is, in this additional sense, a "_cultur-kampf_."
+
+V. Another of the most deplorable aspects of Christian morality is
+its belittlement of the life of the family, of that natural living
+together with our next of kin which is just as necessary in the case
+of man as in the case of all the higher social animals. The family
+is justly regarded as the "foundation of society," and the healthy
+life of the family is a necessary condition of the prosperity of the
+State. Christ, however, was of a very different opinion: with his gaze
+ever directed to "the beyond," he thought as lightly of woman and the
+family as of all other goods of "this life." Of his infrequent contact
+with his parents and sisters the gospels have very little to say; but
+they are far from representing his relations with his mother to have
+been so tender and intimate as they are poetically depicted in so many
+thousands of pictures. He was not married himself. Sexual love, the
+first foundation of the family union, seems to have been regarded by
+Jesus as a necessary evil. His most enthusiastic apostle, Paul, went
+still farther in the same direction, declaring it to be better not to
+marry than to marry: "It is good for a man not to touch a woman." If
+humanity were to follow this excellent counsel, it would soon be rid
+of all earthly misery and suffering: it would be killed off by such a
+"radical cure" within half a century.
+
+VI. As Christ never knew the love of woman, he had no personal
+acquaintance with that refining of man's true nature that comes only
+from the intimate life of man with woman. The intimate sexual union, on
+which the preservation of the human race depends, is just as important
+on that account as the spiritual penetration of the two sexes, or
+the mutual complement which they bring to each other in the practical
+wants of daily life as well as in the highest ideal functions of the
+soul. For man and woman are two different organisms, equal in worth,
+each having its characteristic virtues and defects. As civilization
+advanced, this ideal value of sexual love was more appreciated, and
+woman held in higher honor, especially among the Teutonic races; she
+is the inspiring source of the highest achievements of art and poetry.
+But Christ was as far from this view as nearly the whole of antiquity;
+he shared the idea that prevailed everywhere in the East--that
+woman is subordinate to man, and intercourse with her is "unclean."
+Long-suffering nature has taken a fearful revenge for this blunder; its
+sad consequences are written in letters of blood in the history of the
+papal Middle Ages.
+
+The marvellous hierarchy of the Roman Church, that never disdained any
+means of strengthening its spiritual despotism, found an exceptionally
+powerful instrument in the manipulation of this "unclean" idea, and in
+the promotion of the ascetic notion that abstinence from intercourse
+with women is a virtue of itself. In the first few centuries after
+Christ a number of priests voluntarily abstained from marriage, and
+the supposed value of this celibacy soon rose to such a degree that it
+was made obligatory. In the Middle Ages the seduction of women of good
+repute and of their daughters by Catholic priests (the confessional
+was an active agency in the business) was a public scandal: many
+communities, in order to prevent such things, pressed for a license
+of concubinage to be given to the clergy. And it was done in many,
+and sometimes very romantic, ways. Thus, for instance, the canon law
+that the priest's cook should not be less than forty years old was
+very cleverly "explained" in the sense that the priest might have two
+cooks, one in the presbytery, another without; if one was twenty-four
+and the other eighteen, that made forty-two together--two years above
+the prescribed age. At the Christian councils, at which heretics were
+burned alive, the cardinals and bishops sat down with whole troops
+of prostitutes. The private and public debauchery of the Catholic
+clergy was so scandalous and dangerous to the commonwealth that there
+was a general rebellion against it before the time of Luther, and a
+loud demand for a "reformation of the church in head and members." It
+is well known that these immoral relations still continue in Roman
+Catholic lands, although more in secret. Formerly proposals were
+made from time to time for the definitive abrogation of celibacy, as
+was done, for instance, in the chambers of Baden, Bavaria, Hesse,
+Saxony, and other lands; but they have, unfortunately, hitherto proved
+unavailing. In the German Reichstag, in which the ultramontane Centre
+is now proposing the most ridiculous measures for the suppression of
+sexual immorality, there is now no party that will urge the abolition
+of celibacy in the interest of public morality. The so-called
+"Freethought" Party and the utopian social democracy coquette with the
+favor of the Centre.
+
+The modern state that would lift not only the material, but the moral,
+life of its people to a higher level is entitled, and indeed bound,
+to sweep away such unworthy and harmful conditions. The obligatory
+celibacy of the Catholic clergy is as pernicious and immoral as the
+practice of auricular confession or the sale of indulgences. All
+three have nothing whatever to do with primitive Christianity. All
+three are directly opposed to true Christian morality. All three are
+disreputable inventions of the papacy, designed for the sole purpose of
+strengthening its despotic rule over the credulous masses and making as
+much material profit as possible out of them.
+
+The Nemesis of history will sooner or later exact a terrible account
+of the Roman papacy, and the millions who have been robbed of their
+happiness by this degenerate religion will help to give it its
+death-blow in the coming twentieth century--at least, in every truly
+civilized state. It has been recently calculated that the number of
+men who lost their lives in the papal persecutions of heretics, the
+Inquisition, the Christian religious wars, etc., is much more than
+ten millions. But what is this in comparison with the tenfold greater
+number of the unfortunate _moral_ victims of the institutions and
+the priestly domination of the degenerate Christian Church--with the
+unnumbered millions whose higher mental life was extinguished, whose
+conscience was tortured, whose family life was destroyed, by the
+Church? We may with truth apply the words of Goethe in his _Bride of
+Corinth_:
+
+    "Victims fall, nor lambs nor bulls,
+    But human victims numberless."
+
+In the great _cultur-kampf_, which must go on as long as these sad
+conditions exist, the first aim must be the absolute separation of
+Church and State. There shall be "a free Church in a free State"--that
+is, every Church shall be free in the practice of its special worship
+and ceremonies, and in the construction of its fantastic poetry and
+superstitious dogmas--with the sole condition that they contain no
+danger to social order or morality. Then there will be equal rights
+for all. Free societies and monistic religious bodies shall be equally
+tolerated, and just as free in their movements as Liberal Protestant
+and orthodox ultramontane congregations. But for all these "faithful"
+of the most diverse sects religion will have to be a private concern.
+The state shall supervise them, and prevent excesses; but it must
+neither oppress nor support them. Above all, the ratepayers shall not
+be compelled to contribute to the support and spread of a "faith" which
+they honestly believe to be a harmful superstition. In the United
+States such a complete separation of Church and State has been long
+accomplished, greatly to the satisfaction of all parties. They have
+also the equally important separation of the Church from the school;
+that is, undoubtedly, a powerful element in the great advance which
+science and culture have recently made in America.
+
+It goes without saying that this exclusion of the Church from the
+school only refers to its sectarian principles, the particular form
+of belief which each Church has evolved in the course of its life.
+This sectarian education is purely a private concern, and should be
+left to parents and tutors, or to such priests or teachers as may
+have the personal confidence of the parents. Instead of the rejected
+sectarian instruction, two important branches of education will be
+introduced--monistic or humanist ethics and comparative religion.
+During the last thirty years an extensive literature has appeared
+dealing with the new system of ethics which has been raised on the
+basis of modern science--especially evolutionary science. Comparative
+religion will be a natural companion to the actual elementary
+instruction in "biblical history" and in the mythology of Greece and
+Rome. Both of these will remain in the curriculum. The reason for
+that is obvious enough; the whole of our painting and sculpture, the
+chief branches of monistic æsthetics, are intimately blended with
+the Christian, Greek, and Roman mythologies. There will only be this
+important difference--that the Christian myths and legends will not
+be taught as truths, but as poetic fancies, like the Greek and Roman
+myths; the high value of the ethical and æsthetical material they
+contain will not be lessened, but increased, by this means. As regards
+the Bible, the "book of books" will only be given to the children in
+carefully selected extracts (a sort of "school Bible"); in this way we
+shall avoid the besmirching of the child's imagination with the unclean
+stories and passages which are so numerous in the Old Testament.
+
+Once the modern State has freed itself and its schools from the
+fetters of the Church, it will be able to devote more attention to the
+improvement of education. The incalculable value of a good system of
+education has forced itself more and more upon us as the many aspects
+of modern civilized life have been enlarged and enriched in the
+course of the century. But the development of the educational methods
+has by no means kept pace with life in general. The necessity for a
+comprehensive reform of our schools is making itself felt more and
+more. On this question, too, a number of valuable works have appeared
+in the course of the last forty years. We shall restrict ourselves to
+making a few general observations which we think of special importance.
+
+1. In all education up to the present time _man_ has played the chief
+part, and especially the grammatical study of his language; the study
+of _nature_ was entirely neglected.
+
+2. In the school of the future nature will be the chief object of the
+study; a man shall learn a correct view of the world he lives in; he
+will not be made to stand outside of and opposed to nature, but be
+represented as its highest and noblest product.
+
+3. The study of the classical tongues (Latin and Greek), which has
+hitherto absorbed most of the pupils' time and energy, is indeed
+valuable; but it will be much restricted, and confined to the mere
+elements (obligatory for Latin, optional for Greek).
+
+4. In consequence, modern languages must be all the more cultivated in
+all the higher schools (English and French to be obligatory, Italian
+optional).
+
+5. Historical instruction must pay more attention to the inner
+mental and spiritual life of a nation, and to the development of its
+civilization, and less to its external history (the vicissitudes of
+dynasties, wars, and so forth).
+
+6. The elements of evolutionary science must be learned in conjunction
+with cosmology, geology must go with geography, and anthropology with
+biology.
+
+7. The first principles of biology must be familiar to every educated
+man; the modern training in observation furnishes an attractive
+introduction to the biological sciences (anthropology, zoology, and
+botany). A start must be made with descriptive system (in conjunction
+with ætiology or bionomy); the elements of anatomy and physiology to be
+added later on.
+
+8. The first principles of physics and chemistry must also be taught,
+and their exact establishment with the aid of mathematics.
+
+9. Every pupil must be taught to draw well, and from nature; and,
+wherever it is possible, the use of water-colors. The execution of
+drawings and of water-color sketches from nature (of flowers, animals,
+landscapes, clouds, etc.) not only excites interest in nature and helps
+memory to enjoy objects, but it gives the pupil his first lesson in
+_seeing_ correctly and understanding what he has seen.
+
+10. Much more care and time must be devoted than has been done hitherto
+to corporal exercise, to gymnastics and swimming; but it is especially
+important to have walks in common every week, and journeys on foot
+during the holidays. The lesson in observation which they obtain in
+this way is invaluable.
+
+The chief aim of higher education up to the present time, in most
+countries, has been a preparation for the subsequent profession, and
+the acquisition of a certain amount of information and direction
+for civic duties. The school of the twentieth century will have for
+its main object the formation of independent thought, the clear
+understanding of the knowledge acquired, and an insight into the
+natural connection of phenomena. If the modern state gives every
+citizen a vote, it should also give him the means of developing his
+reason by a proper education, in order to make a rational use of his
+vote for the commonweal.
+
+
+
+
+CHAPTER XX
+
+SOLUTION OF THE WORLD-PROBLEMS
+
+    A Glance at the Progress of the Nineteenth Century in Solving
+    Cosmic Problems--I. Progress of Astronomy and Cosmology--Physical
+    and Chemical Unity of the Universe--Cosmic Metamorphoses--Evolution
+    of the Planetary System--Analogy of the Phylogenetic Processes
+    on the Earth and on Other Planets--Organic Inhabitants of
+    Other Heavenly Bodies--Periodic Variation in the Making of
+    Worlds--II. Progress of Geology and Palæontology--Neptunism and
+    Vulcanism--Theory of Continuity--III. Progress of Physics and
+    Chemistry--IV. Progress of Biology--Cellular Theory and Theory of
+    Descent--V. Anthropology--Origin of Man--General Conclusion
+
+
+At the close of our philosophic study of the riddles of the universe
+we turn with confidence to the answer to the momentous question, How
+nearly have we approached to a solution of them? What is the value of
+the immense progress which the passing nineteenth century has made in
+the knowledge of nature? And what prospect does it open out to us for
+the future, for the further development of our system in the twentieth
+century, at the threshold of which we pause? Every unprejudiced thinker
+who impartially considers the solid progress of our empirical science,
+and the unity and clearness of our philosophic interpretation of it,
+will share our view: the nineteenth century has made greater progress
+in knowledge of the world and in grasp of its nature than all its
+predecessors; it has solved many great problems that seemed insoluble a
+hundred years ago; it has opened out to us new provinces of learning,
+the very existence of which was unsuspected at the beginning of the
+century. Above all, it has put clearly before our eyes the lofty aim of
+monistic cosmology, and has pointed out the path which alone will lead
+us towards it--the way of the exact empirical investigation of facts,
+and of the critical genetic study of their causes. The great abstract
+law of mechanical causality, of which our cosmological law--the law
+of substance--is but another and a concrete expression, now rules
+the entire universe, as it does the mind of man; it is the steady,
+immovable pole-star, whose clear light falls on our path through the
+dark labyrinth of the countless separate phenomena. To see the truth
+of this more clearly, let us cast a brief glance at the astonishing
+progress which the chief branches of science have made in this
+remarkable period.
+
+
+I.--PROGRESS OF ASTRONOMY
+
+The study of the heavens is the oldest, the study of man the youngest,
+of the sciences. With regard to himself and the character of his being
+man only obtained a clear knowledge in the second half of the present
+century; with regard to the starry heavens, the motions of the planets,
+and so on, he had acquired astonishing information forty-five hundred
+years ago. The ancient Chinese, Hindoos, Egyptians, and Chaldæans in
+the distant East knew more of the science of the spheres than the
+majority of educated Christians did in the West four thousand years
+after them. An eclipse of the sun was astronomically observed in China
+in the year 2697 B.C., and the plane of the ecliptic was determined
+by means of a gnome eleven hundred years B.C., while Christ himself
+had no knowledge whatever of astronomy--indeed, he looked out upon
+heaven and earth, nature and man, from the very narrowest geocentric
+and anthropocentric point of view. The greatest advance of astronomy
+is generally, and rightly, said to be the founding of the heliocentric
+system of Copernicus, whose famous work, _De Revolutionibus Orbium
+Celestium_, of itself caused a profound revolution in the minds of
+thoughtful men. In overthrowing the Ptolemaic system, he destroyed the
+foundation of the Christian theory, which regarded the earth as the
+centre of the universe and man as the godlike ruler of the earth. It
+was natural, therefore, that the Christian clergy, with the pope at its
+head, should enter upon a fierce struggle with the invaluable discovery
+of Copernicus. Yet it soon cleared a path for itself, when Kepler and
+Galileo grounded on it their true "mechanics of the heavens," and
+Newton gave it a solid foundation by his theory of gravitation (1686).
+
+A further great advance, comprehending the entire universe, was the
+application of the idea of evolution to astronomy. It was done by
+the youthful Kant in 1755; in his famous general natural history and
+theory of the heavens he undertook the discussion, not only of the
+"constitution," but also of the "mechanical origin" of the whole
+world-structure on Newtonian principles. The splendid _Système du
+Monde_ of Laplace, who had independently come to the same conclusions
+as Kant on the world-problem, gave so firm a basis to this new
+_Mécanique Céleste_ in 1796 that it looked as if nothing entirely
+new of equal importance was left to be discovered in the nineteenth
+century. Yet here again it had the honor of opening out entirely
+new paths and infinitely enlarging our outlook on the universe. The
+invention of photography and photometry, and especially of spectral
+analysis (in 1860 by Bunsen and Kirchoff), introduced physics and
+chemistry into astronomy and led to cosmological conclusions of the
+utmost importance. It was now made perfectly clear that matter is
+the same throughout the universe, and that its physical and chemical
+properties in the most distant stars do not differ from those of the
+earth under our feet.
+
+The monistic conviction, which we thus arrived at, of the physical
+and chemical unity of the entire cosmos is certainly one of the most
+valuable general truths which we owe to astrophysics, the new branch
+of astronomy which is honorably associated with the name of Friedrich
+Zöllner. Not less important is the clear knowledge we have obtained
+that the same laws of mechanical development that we have on the
+earth rule throughout the infinite universe. A vast, all-embracing
+metamorphosis goes on continuously in all parts of the universe,
+just as it is found in the geological history of the earth; it can
+be traced in the evolution of its living inhabitants as surely as in
+the history of peoples or in the life of each human individual. In
+one part of space we perceive, with the aid of our best telescopes,
+vast nebulæ of glowing, infinitely attenuated gas; we see in them the
+embryos of heavenly bodies, billions of miles away, in the first stage
+of their development. In some of these "stellar embryos" the chemical
+elements do not seem to be differentiated yet, but still buried in the
+homogeneous primitive matter (_prothyl_) at an enormous temperature
+(calculated to run into millions of degrees); it is possible that the
+original basic "substance" (_vide_ p. 229) is not yet divided into
+ponderable and imponderable matter. In other parts of space we find
+stars that have cooled down into glowing fluid, and yet others that
+are cold and rigid; we can tell their stage of evolution approximately
+by their color. We find stars that are surrounded with rings and moons
+like Saturn; and we recognize in the luminous ring of the nebula the
+embryo of a new moon, which has detached itself from the mother-planet,
+just as the planet was released from the sun.
+
+Many of the stars, the light of which has taken thousands of years to
+reach us, are certainly suns like our own mother-sun, and are girt
+about with planets and moons, just as in our own solar system. We
+are justified in supposing that thousands of these planets are in a
+similar stage of development to that of our earth--that is, they have
+arrived at a period when the temperature at the surface lies between
+the freezing and boiling point of water, and so permits the existence
+of water in its liquid condition. That makes it possible that carbon
+has entered into the same complex combinations on those planets as
+it has done on our earth, and that from its nitrogenous compounds
+protoplasm has been evolved--that wonderful substance which alone,
+as far as our knowledge goes, is the possessor of organic life. The
+monera (for instance, chromacea and bacteria), which consist only of
+this primitive protoplasm, and which arise by spontaneous generation
+from these inorganic nitrocarbonates, may thus have entered upon the
+same course of evolution on many other planets as on our own; first of
+all, living cells of the simplest character would be formed from their
+homogeneous protoplasmic body by the separation of an inner nucleus
+from the outer cell body (cytostoma). Further, the analogy that we
+find in the life of all cells--whether plasmodomous plant-cells or
+plasmophagous animal-cells--justifies the inference that the further
+course of organic evolution on these other planets has been analogous
+to that of our own earth--always, of course, given the same limits of
+temperature which permit water in a liquid form. In the glowing liquid
+bodies of the stars, where water can only exist in the form of steam,
+and on the cold extinct suns, where it can only be in the shape of ice,
+such organic life as we know is impossible.
+
+The similarity of phylogeny, or the analogy of organic evolution,
+which we may thus assume in many stars which are at the same stage of
+biogenetic development, naturally opens out a wide field of brilliant
+speculation to the constructive imagination. A favorite subject for
+such speculation has long been the question whether there are men, or
+living beings like ourselves, perhaps much more highly developed, in
+other planets? Among the many works which have sought to answer the
+question, those of Camille Flammarion, the Parisian astronomer, have
+recently been extremely popular; they are equally distinguished by
+exuberant imagination and brilliant style, and by a deplorable lack
+of critical judgment and biological knowledge. We may condense in the
+following thesis the present condition of our knowledge on the subject:
+
+I. It is very probable that a similar biogenetic process to that of our
+own earth is taking place on some of the other planets of our solar
+system (Mars and Venus), and on many planets of other solar systems;
+first simple monera are formed by spontaneous generation, and from
+these arise unicellular protists (first plasmodomous primitive plants,
+and then plasmophagous primitive animals).
+
+II. It is very probable that from these unicellular protists arise,
+in the further course of evolution, first social cell-communities
+(coenobia), and subsequently tissue-forming plants and animals
+(metaphyta and metazoa).
+
+III. It is also very probable that thallophyta (algæ and fungi) were
+the first to appear in the plant-kingdom, then diaphyta (mosses and
+ferns), finally anthophyta (gymnosperm and angiosperm flowering plants).
+
+IV. It is equally probable that the biogenetic process took a similar
+course in the animal kingdom--that from the blastæads (catallacta)
+first gastræads were formed, and from these lower animal forms
+(coelenteria) higher organisms (coelomaria) were afterwards evolved.
+
+V. On the other hand, it is very questionable whether the different
+stems of these higher animals (and those of the higher plants as well)
+run through the same course of development on other planets as on our
+earth.
+
+VI. In particular, it is wholly uncertain whether there are vertebrates
+on other planets, and whether, in the course of their phyletic
+development, taking millions of years, mammals are formed as on earth,
+reaching their highest point in the formation of man; in such an event,
+millions of changes would have to be just the same in both cases.
+
+VII. It is much more probable, on the contrary, that other planets
+have produced other types of the higher plants and animals, which are
+unknown on our earth; perhaps from some higher animal stem, which is
+superior to the vertebrate in formation, higher beings have arisen who
+far transcend us earthly men in intelligence.
+
+VIII. The possibility of our ever entering into direct communication
+with such inhabitants of other planets seems to be excluded by the
+immense distance of our earth from the other heavenly bodies, and the
+absence of the requisite atmosphere in the intervening space, which
+contains only ether.
+
+But while many of the stars are probably in a similar stage of
+biogenetic development to that of our earth (for the last one hundred
+million years at least), others have advanced far beyond this stage,
+and, in their planetary old age, are hastening towards their end--the
+same end that inevitably awaits our own globe. The radiation of heat
+into space gradually lowers the temperature until all the water is
+turned into ice; that is the end of all organic life. The substance
+of the rotating mass contracts more and more; the rapidity of its
+motion gradually falls off. The orbits of the planets and of their
+moons grow narrower. At length the moons fall upon the planets, and
+the planets are drawn into the sun that gave them birth. The collision
+again produces an enormous quantity of heat. The pulverized mass of the
+colliding bodies is distributed freely through infinite space, and the
+eternal drama of sun-birth begins afresh.
+
+The sublime picture which modern astrophysics thus unveils before the
+mind's eye shows us an eternal birth and death of countless heavenly
+bodies, a periodic change from one to the other of the different
+cosmogenetic conditions, which we observe side by side in the universe.
+While the embryo of a new world is being formed from a nebula in
+one corner of the vast stage of the universe, another has already
+condensed into a rotating sphere of liquid fire in some far distant
+spot; a third has already cast off rings at its equator, which round
+themselves into planets; a fourth has become a vast sun whose planets
+have formed a secondary retinue of moons, and so on. And between them
+are floating about in space myriads of smaller bodies, meteorites,
+or shooting-stars, which cross and recross the paths of the planets
+apparently like lawless vagabonds, and of which a great number fall
+onto the planets every day. Thus there is a continuous but slow change
+in the velocities and the orbits of the revolving spheres. The frozen
+moons fall onto the planets, the planets onto their suns. Two distant
+suns, perhaps already stark and cold, rush together with inconceivable
+force and melt away into nebulous clouds. And such prodigious heat
+is generated by the collision that the nebula is once more raised to
+incandescence, and the old drama begins again. Yet in this "perpetual
+motion" the infinite substance of the universe, the sum total of its
+matter and energy, remains eternally unchanged, and we have an eternal
+repetition in infinite time of the periodic dance of the worlds, the
+metamorphosis of the cosmos that ever returns to its starting-point.
+Over all rules the law of substance.
+
+
+II.--PROGRESS OF GEOLOGY
+
+The earth and its origin were much later than the heavens in becoming
+the object of scientific investigation. The numerous ancient and modern
+cosmogonies do, indeed, profess to give us as good an insight into the
+origin of the earth as into that of the heavens; but the mythological
+raiment, in which all alike are clothed, betrays their origin in
+poetic fancy. Among the countless legends of creation which we find in
+the history of religions and of thought there is one that soon took
+precedence of all the rest--the Mosaic story of creation as told in
+the first book of the Hexateuch. It did not exist in its present form
+until long after the death of Moses (probably not until eight hundred
+years afterwards); but its sources are much older, and are to be found
+for the most part in Assyrian, Babylonian, and Hindoo legends. This
+Hebrew legend of creation obtained its great influence through its
+adoption into the Christian faith and its consecration as the "Word of
+God." Greek philosophers had already, five hundred years before Christ,
+explained the natural origin of the earth in the same way as that of
+other cosmic bodies. Xenophanes of Colophon had even recognized the
+true character of the fossils which were afterwards to prove of such
+moment; the great painter, Leonardo da Vinci, of the fifteenth century,
+also explained the fossils as the petrified remains of animals which
+had lived in earlier periods of the earth's history. But the authority
+of the Bible, especially the myth of the deluge, prevented any further
+progress in this direction, and insured the triumph of the Mosaic
+legend until about the middle of the last century. It survives even at
+the present day among orthodox theologians. However, in the second half
+of the eighteenth century, scientific inquiry into the structure of the
+crust of the earth set to work independently of the Mosaic story, and
+it soon led to certain conclusions as to the origin of the earth. The
+founder of geology, Werner of Freiberg, thought that all the rocks were
+formed in water, while Voigt and Hutton (1788) rightly contended that
+only the stratified, fossil-bearing rocks had had an aquatic origin,
+and that the Vulcanic or Plutonic mountain ranges had been formed by
+the cooling down of molten matter.
+
+The heated conflict of these "Neptunian" and "Plutonic" schools was
+still going on during the first three decades of the present century;
+it was only settled when Karl Hoff (1822) established the principle of
+"actualism," and Sir Charles Lyell applied it with signal success to
+the entire natural evolution of the earth. The _Principles of Geology_
+of Lyell (1830) secured the full recognition of the supremely important
+theory of continuity in the formation of the earth's crust, as opposed
+to the catastrophic theory of Cuvier.[34] Palæontology, which had
+been founded by Cuvier's work on fossil bones (1812), was of the
+greatest service to geology; by the middle of the present century it
+had advanced so far that the chief periods in the history of the earth
+and its inhabitants could be established. The comparatively thin crust
+of the earth was now recognized with certainty to be the hard surface
+formed by the cooling of an incandescent fluid planet, which still
+continues its slow, unbroken course of refrigeration and condensation.
+The crumpling of the stiffened crust, "the reaction of the molten fiery
+contents on the cool surface," and especially the unceasing geological
+action of water, are the natural causes which are daily at work in the
+secular formation of the crust of the earth and its mountains.
+
+To the brilliant progress of modern geology we owe three extremely
+important results of general import. In the first place, it has
+excluded from the story of the earth all questions of miracle, all
+questions of supernatural agencies, in the building of the mountains
+and the shaping of the continents. In the second place, our idea of
+the length of the vast period of time which had been absorbed in their
+formation has been considerably enlarged. We now know that the huge
+mountains of the palæozoic, mesozoic, and cenozoic formations have
+taken, not thousands, but millions of years in their growth. In the
+third place, we now know that all the countless fossils that are found
+in those formations are not "sports of nature," as was believed one
+hundred and fifty years ago, but the petrified remains of organisms
+that lived in earlier periods of the earth's history, and arose by
+gradual transformation from a long series of ancestors.
+
+
+III.--PROGRESS OF PHYSICS AND CHEMISTRY
+
+The many important discoveries which these fundamental sciences have
+made during the nineteenth century are so well known, and their
+practical application in every branch of modern life is so obvious,
+that we need not discuss them in detail here. In particular, the
+application of steam and electricity has given to our nineteenth
+century its characteristic "machinist-stamp." But the colossal
+progress of inorganic and organic chemistry is not less important. All
+branches of modern civilization--medicine and technology, industry
+and agriculture, mining and forestry, land and water transport--have
+been so much improved in the course of the century, especially in the
+second half, that our ancestors of the eighteenth century would find
+themselves in a new world, could they return. But more valuable and
+important still is the great theoretical expansion of our knowledge
+of nature, which we owe to the establishment of the law of substance.
+Once Lavoisier (1789) had established the law of the persistence of
+matter, and Dalton (1808) had founded his new atomic theory with its
+assistance, a way was open to modern chemistry along which it has
+advanced with a rapidity and success beyond all anticipation. The same
+must be said of physics in respect of the law of the conservation of
+energy. Its discovery by Robert Mayer (1842) and Hermann Helmholtz
+(1847) inaugurated for this science also a new epoch of the most
+fruitful development; for it put physics in a position to grasp the
+universal unity of the forces of nature and the eternal play of natural
+processes, in which one force may be converted into another at any
+moment.
+
+
+IV.--PROGRESS OF BIOLOGY
+
+The great discoveries which astronomy and geology have made during the
+nineteenth century, and which are of extreme importance to our whole
+system, are, nevertheless, far surpassed by those of biology. Indeed,
+we may say that the greater part of the many branches which this
+comprehensive science of organic life has recently produced have seen
+the light in the course of the present century. As we saw in the first
+section, during the century all branches of anatomy and physiology,
+botany and zoology, ontogeny and phylogeny, have been so marvellously
+enriched by countless discoveries that the present condition of
+biological science is immeasurably superior to its condition a hundred
+years ago. That applies first of all _quantitatively_ to the colossal
+growth of our positive information in all those provinces and their
+several parts. But it applies with even greater force _qualitatively_
+to the deepening of our comprehension of biological phenomena, and
+our knowledge of their efficient causes. In this Charles Darwin
+(1859) takes the palm of victory; by his theory of selection he has
+solved the great problem of "organic creation," of the natural
+origin of the countless forms of life by gradual transformation. It
+is true that Lamarck had recognized fifty years earlier that the
+mode of this transformation lay in the reciprocal action of heredity
+and adaptation. However, Lamarck was hampered by his lack of the
+principle of selection, and of that deeper insight into the true
+nature of organization which was only rendered possible after the
+founding of the theory of evolution and the cellular theory. When we
+collated the results of these and other disciplines, and found the
+key to their harmonious interpretation in the ancestral development
+of living beings, we succeeded in establishing the monistic biology,
+the principles of which I have endeavored to lay down securely in my
+_General Morphology_.
+
+
+V.--PROGRESS OF ANTHROPOLOGY
+
+In a certain sense, the true science of man, rational anthropology,
+takes precedence of every other science. The saying of the ancient
+sage, "Man, know thyself," and that other famous maxim, "Man is the
+measure of all things," have been accepted and applied from all time.
+And yet this science--taking it in its widest sense--has languished
+longer than all other sciences in the fetters of tradition and
+superstition. We saw in the first section how slowly and how late
+the science of the human organism was developed. One of its chief
+branches--embryology--was not firmly established until 1828 (by Baer),
+and another, of equal importance--the cellular theory--until 1838 (by
+Schwann). And it was even later still when the answer was given to the
+"question of all questions," the great riddle of the origin of man.
+Although Lamarck had pointed out the only path to a correct solution
+of it in 1809, and had affirmed the descent of man from the ape, it
+fell to Darwin to establish the affirmation securely fifty years
+afterwards, and to Huxley to collect the most important proofs of it
+in 1863, in his _Place of Man in Nature_. I have myself made the first
+attempt, in my _Anthropogeny_ (1874), to present in their historical
+connection the entire series of ancestors through which our race has
+been slowly evolved from the animal kingdom in the course of many
+millions of years.
+
+
+
+
+CONCLUSION
+
+
+The number of world-riddles has been continually diminishing in the
+course of the nineteenth century through the aforesaid progress of a
+true knowledge of nature. Only one comprehensive riddle of the universe
+now remains--the problem of substance. What is the real character of
+this mighty world-wonder that the realistic scientist calls Nature or
+the Universe, the idealist philosopher calls Substance or the Cosmos,
+the pious believer calls Creator or God? Can we affirm to-day that the
+marvellous progress of modern cosmology has solved this "problem of
+substance," or at least that it has brought us nearer to the solution?
+
+The answer to this final question naturally varies considerably
+according to the stand-point of the philosophic inquirer and his
+empirical acquaintance with the real world. We grant at once that the
+innermost character of nature is just as little understood by us as it
+was by Anaximander and Empedocles twenty-four hundred years ago, by
+Spinoza and Newton two hundred years ago, and by Kant and Goethe one
+hundred years ago. We must even grant that this essence of substance
+becomes more mysterious and enigmatic the deeper we penetrate into the
+knowledge of its attributes, matter and energy, and the more thoroughly
+we study its countless phenomenal forms and their evolution. We do not
+know the "thing in itself" that lies behind these knowable phenomena.
+But why trouble about this enigmatic "thing in itself" when we have
+no means of investigating it, when we do not even clearly know whether
+it exists or not? Let us, then, leave the fruitless brooding over this
+ideal phantom to the "pure metaphysician," and let us instead, as "real
+physicists," rejoice in the immense progress which has been actually
+made by our monistic philosophy of nature.
+
+Towering above all the achievements and discoveries of the century
+we have the great, comprehensive "law of substance," the fundamental
+law of the constancy of matter and force. The fact that substance is
+everywhere subject to eternal movement and transformation gives it the
+character also of the universal law of evolution. As this supreme law
+has been firmly established, and all others are subordinate to it, we
+arrive at a conviction of the universal unity of nature and the eternal
+validity of its laws. From the gloomy _problem_ of substance we have
+evolved the clear _law_ of substance. The monism of the cosmos which we
+establish thereon proclaims the absolute dominion of "the great eternal
+iron laws" throughout the universe. It thus shatters, at the same time,
+the three central dogmas of the dualistic philosophy--the personality
+of God, the immortality of the soul, and the freedom of the will.
+
+Many of us certainly view with sharp regret, or even with a profound
+sorrow, the death of the gods that were so much to our parents and
+ancestors. We must console ourselves in the words of the poet:
+
+    "The times are changed, old systems fall,
+    And new life o'er their ruins dawns."
+
+The older view of idealistic dualism is breaking up with all its mystic
+and anthropistic dogmas; but upon the vast field of ruins rises,
+majestic and brilliant, the new sun of our realistic monism, which
+reveals to us the wonderful temple of nature in all its beauty. In the
+sincere cult of "the true, the good, and the beautiful," which is the
+heart of our new monistic religion, we find ample compensation for the
+anthropistic ideals of "God, freedom, and immortality" which we have
+lost.
+
+Throughout this discussion of the riddles of the universe I have
+clearly defined my consistent monistic position and its opposition
+to the still prevalent dualistic theory. In this I am supported by
+the agreement of nearly all modern scientists who have the courage to
+accept a rounded philosophical system. I must not, however, take leave
+of my readers without pointing out in a conciliatory way that this
+strenuous opposition may be toned down to a certain degree on clear
+and logical reflection--may, indeed, even be converted into a friendly
+harmony. In a thoroughly logical mind, applying the highest principles
+with equal force in the entire field of the cosmos--in both organic and
+inorganic nature--the antithetical positions of theism and pantheism,
+vitalism and mechanism, approach until they touch each other.
+Unfortunately, consecutive thought is a rare phenomenon in nature. The
+great majority of philosophers are content to grasp with the right hand
+the pure knowledge that is built on experience, but they will not part
+with the mystic faith based on revelation, to which they cling with the
+left. The best type of this contradictory dualism is the conflict of
+pure and practical reason in the critical philosophy of the most famous
+of modern thinkers, Immanuel Kant.
+
+On the other hand, the number is always small of the thinkers who
+will boldly reject dualism and embrace pure monism. That is equally
+true of consistent idealists and theists, and of logical realists and
+pantheists. However, the reconciliation of these apparent antitheses,
+and, consequently, the advance towards the solution of the fundamental
+riddle of the universe, is brought nearer to us every year in the
+ever-increasing growth of our knowledge of nature. We may, therefore,
+express a hope that the approaching twentieth century will complete
+the task of resolving the antitheses, and, by the construction of a
+system of pure monism, spread far and wide the long-desired unity
+of world-conception. Germany's greatest thinker and poet, whose one
+hundred and fiftieth anniversary will soon be upon us--Wolfgang
+Goethe--gave this "philosophy of unity" a perfect poetic expression,
+at the very beginning of the century, in his immortal poems, _Faust_,
+_Prometheus_, and _God and the World_:
+
+    "By eternal laws
+    Of iron ruled,
+    Must all fulfil
+    The cycle of
+    Their destiny."
+
+
+
+
+FOOTNOTES:
+
+[1] There are two English translations, _The Evolution of Man_ (1879)
+and _The Pedigree of Man_ (1880).
+
+[2] The English translation, by Dr. Hans Gadow, bears the title of _The
+Last Link_.
+
+[3] English translation, by J. Gilchrist, with the title of _Monism_.
+
+[4] E. Haeckel, _Systematische Phylogenie_, 1895, vol. iii., pp.
+646-50. (Anthropolatry means "A divine worship of human nature.")
+
+[5] Cf. my Cambridge lecture, _The Last Link_, "Geological Time and
+Evolution."
+
+[6] As to induction and deduction, _vide_ _The Natural History of
+Creation_.
+
+[7] Rudolph Virchow, _Die Gründung der Berliner Universität und der
+Uebergang aus dem Philosophischen in das naturwissenschaftliche
+Zeitalter_. (Berlin; 1893.)
+
+[8] Cf. chap. iv. of my _General Morphology_, 1866; _Kritik der
+naturwissenschaftlichen Methoden_.
+
+[9] _Systematische Phylogenie_, 1896, part iii., pp. 490, 494, and 496.
+
+[10] Translated in the International Science Series, 1872.
+
+[11] _Zell-Seelen und Seelen-Zellen._ Ernst Haeckel, _Gesammelte
+populäre Vorträge. I. Heft._ 1878.
+
+[12] Cf. E. Haeckel, _The Systems of Darwin, Goethe, and Lamarck_.
+Lecture given at Eisenach in 1882.
+
+[13] _Vide_ the translation of Dr. Hans Gadow: _The Last Link_. (A. &
+C. Black.)
+
+[14] Cf. Max Verworn, _Psychophysiologische Protisten-Studien_, pp.
+135, 140.
+
+[15] E. Haeckel, "General Natural History of the Radiolaria"; 1887.
+
+[16] _Vide Natural History of Creation_, E. Haeckel.
+
+[17] Law of individual variation. _Vide_ _Natural History of Creation_.
+
+[18] Cf. E. Haeckel, _Systematic Phylogeny_, vol. i.
+
+[19] Cf. _Anthropogeny_ and _Natural History of Creation_.
+
+[20] Cf. _Natural History of Creation_.
+
+[21] See chaps. xvi. and xvii. of my _Anthropogeny_.
+
+[22] E. Haeckel, _A Visit to Ceylon_.
+
+[23] Cf. _Monism_, by Ernst Haeckel.
+
+[24] Cf. _Monism_, by Ernst Haeckel.
+
+[25] Cf. _Monism_, by Ernst Haeckel.
+
+[26] Reinke, _Die Welt als That_ (1899).
+
+[27] Cf. _Monism_, by Ernst Haeckel.
+
+[28] _The Last Link_, translated by Dr. Gadow.
+
+[29] _General Morphology_, book 2, chap. v.
+
+[30] Cf. _General Morphology_, vol. ii., and _The Natural History of
+Creation._
+
+[31] _Vide_ _A Visit to Ceylon_, E. Haeckel, translated by C. Bell.
+
+[32] _Collected Popular Lectures_; Bonn, 1878.
+
+[33] As to the Greek paternity of Christ, _vide_ p. 328.
+
+[34] Cf. _The Natural History of Creation_, chaps. iii., vi., xv., and
+xvi.
+
+
+
+
+INDEX
+
+
+ Abiogenesis, 257, 369.
+
+ Abortive organs, 264.
+
+ Accidents, 216.
+
+ Acrania, 166.
+
+ Action at a distance, 217.
+
+ Actualism, 249.
+
+ Æsthesis, 225.
+
+ Affinity, 224.
+
+ Altruism, 350.
+
+ Amphibia, 167.
+
+ Amphimixis, 141.
+
+ Ampitheism, 278.
+
+ Ananke, 272.
+
+ Anatomy, 22, etc.
+   comparative, 24.
+
+ Anaximander, 289, 379.
+
+ Anthropism, 11.
+
+ Anthropistic illusion, 14, etc.
+   world-theory, 13.
+
+ Anthropocentric dogma, 11, etc.
+
+ Anthropogeny, 83.
+
+ Anthropolatric dogma, 12.
+
+ Anthropomorpha, 36.
+
+ Anthropomorphic dogma, 12.
+
+ Apes, 36, 37, 167.
+   anthropoid, 37.
+
+ Archæus, 43.
+
+ Archigony, 257.
+
+ Aristotle, 23, 268.
+
+ Association, centres of, 183.
+   of ideas, 121.
+   of presentations, 121, 122.
+
+ Astronomy, progress of, 366.
+
+ Astro-physics, 368.
+
+ Atavism, 142.
+
+ Athanatism, 189.
+
+ Athanatistic illusions, 205.
+
+ Atheism, 290.
+
+ Atheistic science, 260.
+
+ Atom, the, 222.
+
+ Atomism, 223.
+
+ Atomistic consciousness, 187.
+
+ Attributes of ether, 227.
+   of substance, 216.
+
+ Augustine of Hippo, 130.
+
+ Auricular confession, 319, 359.
+
+ Autogony, 257.
+
+
+ Baer (Carl Ernst), 57.
+
+ Bastian (Adolf), 103.
+
+ Beginning of the world, 240, 247.
+
+ Bible, the, 282, 362.
+
+ Biogenesis, 257.
+
+ Biogenetic law, 81, 143.
+
+ Bismarck, 334.
+
+ Blastoderm, 150, 155.
+
+ Blastosphere, 153.
+
+ Blastula, 153.
+
+ Bruno (Giordano), 290, 317.
+
+ Büchner (Ludwig), 93.
+
+ Buddhism, 326, 355.
+
+
+ Calvin, 130.
+
+ Canonical gospels, 312.
+
+ Carbon as creator, 256.
+   theory, 257.
+
+ Catarrhinæ, 35.
+
+ Catastrophic theory, 74.
+
+ Categorical imperative, 350.
+
+ Causes, efficient, 258.
+   final, 258.
+
+ Celibacy, 358.
+
+ Cell-love, 137.
+   community, soul of the, 155.
+   soul, 151.
+   state, 157.
+
+ Cellular pathology, 50.
+   physiology, 48.
+   psychology, 153, 177.
+   theory, 26.
+
+ Cenobitic soul, 155.
+
+ Cenogenesis, 82.
+   of the psyche, 144.
+
+ Chance, 274.
+
+ Chemicotropism, 64, 136.
+
+ Chordula, 64.
+
+ Chorion, 68.
+
+ Christ, father of, 327.
+
+ Christian art, 339.
+   civilization, 356.
+   contempt of the body, 354.
+     animals, 355.
+     nature, 355.
+     self, 353.
+     the family, 357.
+     woman, 358.
+   ethics, 352.
+
+ Christianity, 347.
+
+ Church and school, 362.
+   state, 361.
+
+ Cnidaria, 161.
+
+ Conception, 64.
+
+ Concubinage of the clergy, 358.
+
+ Confession of faith, 302.
+
+ Consciousness, 170.
+   animal, 176.
+   atomistic, 178.
+   biological, 176.
+   cellular, 177.
+   development of, 185.
+   dualistic, 182.
+   human, 173.
+   monistic, 182.
+   neurological, 174.
+   ontogeny of, 186.
+   pathology of, 182.
+   physiological, 180.
+   transcendental, 180.
+
+ Constancy of energy, 212, 231.
+   matter, 212.
+
+ Constantine the Great, 316.
+
+ Constellations of substance, 218.
+
+ Conventional lies, 323.
+
+ Copernicus, 24, 320, 367.
+
+ Cosmic immortality, 191.
+
+ Cosmogonies, 234.
+
+ Cosmological dualism, 257.
+   creationism, 235.
+   law, 211.
+   perspective, 14.
+
+ Cosmos, the, 229.
+
+ Creation, 73, 79, 234.
+   cosmological, 235.
+   dualistic, 236.
+   heptameral, 237.
+   individual, 237.
+   myths of, 236.
+   periodic, 237.
+   trialistic, 237.
+
+ Cultur-kampf, 334.
+
+ Cuvier, 74.
+
+ Cyclostomata, 167.
+
+ Cynopitheci, 46.
+
+ Cytology, 26, etc.
+
+ Cytopsyche, 151.
+
+ Cytula, 64.
+
+
+ Darwin (Charles), 78, etc.
+
+ Decidua, 69.
+
+ Deduction, 16.
+
+ Demonism, 276.
+
+ Descartes, 99, 355.
+
+ Descent of the ape, 85, etc.
+   of man, 87.
+   theory of, 77.
+
+ Design, 264, 266.
+   in nature, 260.
+   in organisms, 266.
+   in selection, 261.
+
+ Destruction of heavenly bodies, 243.
+
+ Determinists, 130.
+
+ Diaphragm, 31.
+
+ Division of labor in matter, 229.
+
+ Draper, 309, 333.
+
+ Dualism, 20, etc.
+
+ Du Bois-Reymond, 15 180, 235.
+
+ Du Prel (Carl), 305.
+
+ Duty, feeling of, 350.
+
+ Dynamodes, 216.
+
+ Dysteleology, 260.
+
+ Echinodermata, 62.
+
+ Ectoderm, 160.
+   sense-cells in the, 293.
+
+ Egoism, 350.
+
+ Elements, chemical, 222.
+   system of the, 222.
+
+ Embryo, human, 64.
+
+ Embryology, 54.
+
+ Embryonic psychogeny, 144.
+   sleep, 146.
+
+ Empedocles, 23, 224.
+
+ Encyclica (of Pius IX.), 323.
+
+ End of the world, 247.
+
+ Energy, kinetic, 231.
+   potential, 231.
+   principle of, 230.
+   specific, 294.
+
+ Entelecheia, 268.
+
+ Entoderm, 160.
+
+ Entropy of the universe, 247.
+
+ Epigenesis, 56, 133.
+
+ Ergonomy of matter, 229.
+
+ Eternity of the world, 242.
+
+ Ether, 225.
+
+ Etheric souls, 199.
+
+ Ethics, fundamental law of, 350.
+
+ Evolution, theory of, 54, 239, 243.
+   chief element in, 267.
+
+ Experience, 16.
+
+ Extra-mundane God, 288.
+
+
+ Faith, confession of, 303.
+   of our fathers, 304.
+
+ Family, the, and Christianity, 357.
+
+ Fate, 272.
+
+ Fechner, 97, etc.
+
+ Fecundation, 63.
+
+ Fetishism, 276.
+
+ Feuerbach (Ludwig), 295.
+
+ Flechsig, 183.
+
+ Foetal membranes, 66.
+
+ Folk-psychology, 103.
+
+ Forces, conversion of, 231.
+
+ Frederick the Great, 194, 315.
+
+
+ Galen, 23, 40.
+
+ Gaseous souls, 199.
+   vertebrates, 288.
+
+ Gastræa, 160.
+   theory of the, 60.
+
+ Gastræads, 159.
+
+ Gastrula, 61.
+
+ Gegenbaur, 25, 30.
+
+ Generation, theory of, 55.
+
+ Genus, 73.
+
+ Geology, periods of, 270.
+   progress of, 373.
+
+ Germinal disk, 57.
+
+ Gills, 65.
+
+ God, 275.
+   the father, 277.
+   the son, 277, 328.
+
+ Goethe, 20, etc.
+
+ Goethe's monism, 331.
+
+ Golden Rule, the, 351.
+
+ Gospels, 312.
+
+ Gravitation, theory of, 217.
+
+ Gut-layer, 159.
+
+
+ Haller, 42.
+
+ Harvey, 42.
+
+ Helmholtz (Hermann), 213, 230.
+
+ Heredity, psychic, 138.
+
+ Hertz (Heinrich), 225.
+
+ Hippocrates, 23.
+
+ Histology, 26.
+
+ Histopsyche, 156.
+
+ Hoff (Carl), 250.
+
+ Holbach (Paul), 193.
+
+ Holy Ghost, 277, 326.
+
+ Humboldt (Alexander), 343.
+
+ Hydra, 161.
+
+ Hylozoism, 289.
+
+ Hypothesis, 299.
+
+
+ Iatrochemicists, 45.
+
+ Iatromechanicists, 45.
+
+ Ideal of beauty, 338.
+   of truth, 337.
+   of virtue, 339.
+
+ Ignorabimus, 180.
+
+ Immaculate conception, 326.
+
+ Immaterial substance, 221.
+
+ Immortality of animals, 201.
+   of the human soul, 188.
+   of unicellular organisms, 190.
+   personal, 192.
+
+ Imperfection of nature, 264.
+
+ Imponderable matter, 225.
+
+ Impregnation, 64.
+
+ Indeterminists, 130.
+
+ Induction, 16.
+
+ Indulgences, 359.
+
+ Infallibility of the pope, 324.
+
+ Instinct, 105, 123.
+
+ Intellect, 125, etc.
+
+ Intramundane God, 288.
+
+ Introspective psychology, 95.
+
+ Islam, 284.
+
+
+ Janssen (Johannes), 316.
+
+ Jehovah, 283.
+
+ Journeys on foot, 364.
+
+
+ Kant, 258, etc.
+
+ Kant's metamorphosis, 92, etc.
+
+ Kinetic energy, 231.
+   theory of substance, 216.
+
+ Kölliker, 26, 48.
+
+
+ Lamarck, 76, etc.
+
+ Lamettrie, 194.
+
+ Landscape-painting, 343.
+
+ Language, 126.
+   study of, 363.
+
+ Last judgment, 209.
+
+ Lavoisier, 212.
+
+ Leap of the gospels, miraculous, 312.
+
+ Leydig, 27.
+
+ Life, definition of, 39.
+
+ Limits of our knowledge, 182.
+
+ Love, 357.
+   of animals, 355.
+   of neighbor, 350.
+   of self, 350.
+
+ Lucretius Carus, 290.
+
+ Lunarism, 281.
+
+ Luther, 320.
+
+ Lyell, 77, 250.
+
+
+ Madonna, cult of the, 284, 327.
+
+ Malphigi, 54.
+
+ Mammals, 30, etc.
+
+ Mammary glands, 31.
+
+ Man, ancestors of, 82.
+
+ Marsupials, 32, 86.
+
+ Mass, 222.
+
+ Materialism, 20.
+
+ Mayer (Robert), 213, 377.
+
+ Mechanical causality, 366.
+   explanation, 259.
+   theory of heat, 247.
+
+ Mechanicism, 259.
+
+ Mediterranean religions, the, 282.
+
+ Memory, cellular, 12O.
+   conscious, 121.
+   histionic, 121.
+   unconscious, 121.
+
+ Mephistopheles, 279.
+
+ Metabolism, 232.
+
+ Metamorphoses of the cosmos, 372.
+   of philosophers, 92.
+
+ Metaphyta, 156.
+
+ Metasitism, 153.
+
+ Metazoa, 60, 157.
+
+ Middle Ages, 315, 358.
+
+ Mixotheism, 286.
+
+ Mohammedanism, 284.
+
+ Mohr (Friedrich), 213.
+
+ Monera, 257, 369.
+
+ Monism, 20, and _passim_.
+   of energy, 254.
+   of Spinoza, 331.
+   of the cosmos, 255.
+
+ Monistic anthropogeny, 252.
+   art, 341.
+   biogeny, 251.
+   churches, 345.
+   cosmology, 368.
+   ethics, 347.
+   geogeny, 248.
+
+ Monotheism, 279.
+
+ Monotrema, 32.
+
+ Moon-worship, 281.
+
+ Moral order of the universe, 269.
+
+ Morula, 155.
+
+ Mosaism, 283.
+
+ Müller (Johannes), 25, 45, 262.
+
+ Mythology of the soul, 135.
+
+
+ Natural religion, 344.
+
+ Navel-cord, 69.
+
+ Neokantians, 349.
+
+ Neovitalism, 264.
+
+ Neptunian geology, 375.
+
+ Neuro-muscular cells, 114.
+
+ Neuroplasm, 91, 109.
+
+ Neuropsyche, 162.
+
+ Nomocracy, 9.
+
+
+ Ontogenetic psychology, 103.
+
+ Ontological creationism, 235.
+   methods, 249.
+
+ Orbits of the heavenly bodies, 241.
+
+ Origin of movement, 15, 241.
+   of feeling, 15, 241.
+
+ Ovary, 63.
+
+
+ Palingenesis, 82.
+   of the psyche, 143.
+
+ Pandera (the father of Christ), 328.
+
+ Pantheism, 288.
+
+ Papacy, 314.
+
+ Papal ethics, 359.
+
+ Papiomorpha, 37.
+
+ Paul, 313, 357.
+   epistles of, 312.
+
+ Paulinism, 313.
+
+ Pedicle of the allantois, 69.
+
+ Perpetual motion, 245.
+
+ Persistence of force, 212, 231.
+   of matter, 212.
+
+ Phroneta, 293.
+
+ Phylogeny, 71, 81.
+   of the apes, 51.
+   systematic, 81.
+
+ Physiology, 39.
+
+ Phytopsyche, 157.
+
+ Pithecanthropus, 87.
+
+ Pithecoid theory, 82, etc.
+
+ Pithecometra-thesis, 69, 85.
+
+ Placenta, 32, 68.
+
+ Placentals, 32, 86.
+
+ Plasmodoma, 153.
+
+ Plasmogony, 257.
+
+ Plasmophaga, 154.
+
+ Plato, 99, 197.
+
+ Plato's theory of ideas, 269.
+
+ Platodaria, 160.
+
+ Platodes, 160.
+
+ Platyrrhinæ, 35.
+
+ Pneuma zoticon, 40.
+
+ Polytheism, 276.
+
+ Ponderable matter, 222.
+
+ Preformation theory, 54.
+
+ Primaria, 33.
+
+ Primates, 33, 86.
+
+ Primitive Christianity, 311.
+   gut, 61, 161.
+
+ Prodynamis, 216.
+
+ Progaster, 161.
+
+ Proplacentals, 85.
+
+ Prosimiæ, 34.
+
+ Prostoma, 161.
+
+ Prothyl, 223.
+
+ Protoplasm, 90.
+
+ Protozoa, 60.
+
+ Provertebræ, 166.
+
+ Pseudo-Christianity, 321.
+
+ Psychade theory, 178.
+
+ Psyche, 88.
+
+ Psychogeny, 135.
+   phyletic, 149.
+   post-embryonic, 146.
+
+ Psychology, 88 et seqq.
+   ontogenetic, 104.
+   phylogenetic, 104.
+
+ Psychomonism, 226.
+
+ Psychophysics, 97.
+
+ Psychoplasm, 91, 110.
+
+ Pupa, sleep of the, 146.
+
+ Pyknosis, 218.
+
+ Pyknotic theory of substance, 218.
+
+
+ Reason, 17, 125.
+
+ Reflex action, 112.
+   arches, 114.
+
+ Reformation, the, 319.
+
+ Religion a private concern, 361.
+
+ Remak, 58.
+
+ Revelation, 306.
+
+ Reversion, 142.
+
+ Romance of the Virgin Mary, 327.
+
+ Romanes, 106.
+
+ Rudimentary organs, 264.
+
+
+ Saints, 284.
+
+ Scale of emotion, 127.
+   of memory, 120.
+   of movement, 111.
+   of presentation, 118.
+   of reason, 122.
+   of reflex action, 113.
+   of will, 127.
+
+ Scatulation theory, 55.
+
+ Schleiden, 26, 47.
+
+ School, and Church, 361.
+   and State, 362.
+   reform of the, 363.
+
+ Schwann, 26, 47.
+
+ Selachii, 166.
+
+ Selection, theory of, 79.
+
+ Self-consciousness, 171.
+
+ Sense-knowledge, 297.
+   organs, 293.
+
+ Senses, philosophy of the, 295.
+
+ Sentiment, 17, etc., 331.
+
+ Siebold, 27.
+
+ Simiæ, 34.
+
+ Social duties, 351.
+   instincts, 350.
+
+ Solar systems, 241, 369.
+
+ Solarism, 280.
+
+ Soul, 88 _et seqq._
+   apparatus of the, 162.
+   blending of the, 141.
+   creation of the, 135.
+   division of the, 135.
+   etheric, 199.
+   gaseous, 199.
+   histionic, 157.
+   history of the, 167.
+   hydra, 161.
+   life of the, 90.
+   liquid, 200.
+   mammal, 167.
+   nerve, 162.
+   origin of the, 135.
+   of the plant, 157.
+   personal, 162.
+   solid, 201.
+   substance of the, 198.
+   transmigration of the, 135.
+
+ Sources of knowledge, 293.
+
+ Space and time, 244.
+   infinity of, 242.
+   reality of, 244.
+
+ Species, 73.
+
+ Spectral analysis, 241.
+
+ Spermarium, 63.
+
+ Spermatozoa, 58.
+
+ Spinal cord, 165.
+
+ Spinoza, 21, 215, 290.
+
+ Spirit world, 221.
+
+ Spirit-rapping, 305.
+
+ Spiritism, 304.
+
+ Spiritualism, 20.
+
+ Sponge, soul of the, 161.
+
+ Stem-cell, 63, 138, 151.
+
+ Stimulated movement, 113, 116.
+
+ Stimuli, conduction of, 158.
+
+ Strauss (David), 309, 313.
+
+ Struggle for life, 270.
+
+ Substance, 215.
+   law of, 211, etc.
+   structure of, 229.
+
+ Superstition, 301.
+
+ Süss (Edward), 250.
+
+ Syllabus, 323.
+
+ Synodikon (of Pappus), 312.
+
+
+ Table-turning, 305.
+
+ Teleological explanation, 259.
+
+ Teleology, 258.
+
+ Tetrapoda, 29.
+
+ Thanatism, 189.
+   primary, 192.
+   secondary, 192.
+
+ Theism, 276.
+
+ Theocracy, 9.
+
+ Theory, 299.
+
+ Thought, organs of, 126, 183, 293.
+
+ Time and space, 244.
+   reality of, 246.
+
+ Tissue, theory of, 26.
+
+ Tissue-forming animals, 157.
+   plants, 156.
+
+ Transformism, 76.
+
+ Trimurti, 278.
+
+ Trinity, dogma of the, 277.
+   monistic, 336.
+
+ Triplotheism, 277.
+
+ Tropesis, 225.
+
+ Tropismata, 128.
+
+ Tunicata, 165.
+
+ Turbellaria, 161.
+
+
+ Ultramontanism, 310.
+
+ Understanding, 125.
+
+ Unity of natural forces, 231.
+   of substance, 214.
+
+ Universum perpetuum mobile, 245.
+
+ Uterus, 34.
+
+
+ Vaticanism, 314.
+
+ Vertebrates, 27, _passim_.
+
+ Verworn (Max), 48, 116.
+
+ Vesalius, 24.
+
+ Vibration, theory of, 216.
+
+ Virchow, 26, 50.
+
+ Virchow's metamorphosis, 93.
+
+ Vital force, 42, 262.
+
+ Vitalism, 43, 262.
+
+ Vivisection, 41.
+
+ Vogt (Carl), 93.
+
+ Vogt (J.E.), 218.
+
+
+ Water-color drawing, 364.
+
+ Weismann, 190.
+
+ Will, liberty of the, 129.
+   scale of the, 128.
+
+ Wolff (C.F.), 56.
+
+ Woman and Christianity, 358.
+
+ World-consciousness, 171.
+
+ World-riddles, number of, 15.
+
+ Wundt (Wilhelm), 100, 171.
+
+
+                                THE END
+
+
+
+
+    Transcriber's notes:
+
+    The following is a list of changes made to the original.
+    The first line is the original line, the second the corrected one.
+
+    (12) Consequently, the so-called history of the world"
+    (12) Consequently, the so-called "history of the world"
+
+    structure of the primates forces us to distingiush two
+    structure of the primates forces us to distinguish two
+
+    of the geneaology of our race; for man bears all the
+    of the genealogy of our race; for man bears all the
+
+    world of which we have direct and certain cognizanze
+    world of which we have direct and certain cognizance
+
+    the law of substance by Robert Mayer and Helmholz
+    the law of substance by Robert Mayer and Helmholtz
+
+    The more impotant of these works we owe to Romanes
+    The more important of these works we owe to Romanes
+
+    Formerly assistant and pupil of Helmholz, Wundt had early
+    Formerly assistant and pupil of Helmholtz, Wundt had early
+
+    all other viviporous animals, precisely because the complete
+    all other viviparous animals, precisely because the complete
+
+    recent students of the protists, afford conlcusive evidence
+    recent students of the protists, afford conclusive evidence
+
+    a thinker is very striking; in explaning it, it is not
+    a thinker is very striking; in explaining it, it is not
+
+    "have no individuals and no generations in the matazoic sense."
+    "have no individuals and no generations in the metazoic sense."
+
+    in his _Species and Studies_ in his eighty-fouth year
+    in his _Species and Studies_ in his eighty-fourth year
+
+    Chief Forms of Theism--Polytheism--Tritheism--Ampitheism
+    Chief Forms of Theism--Polytheism--Triplotheism--Amphitheism
+
+    faith, and that all these insiduous institutions are
+    faith, and that all these insidious institutions are
+
+    nor in the narnow prisons of our jail-like schools,
+    nor in the narrow prisons of our jail-like schools,
+
+    And it was done in many, and sometimes very romatic, ways.
+    And it was done in many, and sometimes very romantic, ways.
+
+
+
+
+
+End of the Project Gutenberg EBook of The Riddle of the Universe at the
+close of the nineteenth century, by Ernst Haeckel
+
+*** END OF THE PROJECT GUTENBERG EBOOK 42968 ***