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.