diff options
Diffstat (limited to '42968-0.txt')
| -rw-r--r-- | 42968-0.txt | 12120 |
1 files changed, 12120 insertions, 0 deletions
diff --git a/42968-0.txt b/42968-0.txt new file mode 100644 index 0000000..0403175 --- /dev/null +++ b/42968-0.txt @@ -0,0 +1,12120 @@ +*** 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 *** |