In the second decade of the nineteenth century, Oken had inspired the formation of large public gatherings of German naturalists and physicians. Oken was one of the advanced thinkers who felt that all technical science was in the end only preparatory to the great work of educating the people. In his opinion the naturalist, even if he spent his whole life in investigating the filaments of plants or the limbs of insects, was a pioneer of culture. In any case these gatherings were a very good practical move at the time. In a time of terrible reaction on all sides a feeling came at last even to the recluse of science that, besides the technical value of his work, it ought to do something towards lifting his fellows out of the rut they were falling into. They felt that if all ideals were going to be lost, the ultimate aim of special research would perish with them. Oken took up a position of democratic opposition. He was soon joined by Alexander von Humboldt, who, with the same feeling at heart, gave the work a certain polish of scientific and impartial dignity. There are features of his work that amuse us to-day, but those were evil days, and every particle of goodwill had to be appreciated. However, there was a serious difficulty.

The bolder elements met in congresses, and encouraged each other in the pursuit of their ideal. But it at once became clear in their public discussions that some of their purely scientific discoveries were dangerous and heretical in such a period of reaction. This or that had hitherto been buried innocently in scientific monographs, quite unknown to the crowd, and the author might be a royal councillor, receive decorations, and almost be an elder of the Church. Suddenly, by means of these assemblies, the sinfulness of all this lore about snails or insects or vertebrates was brought to light and put before the profane public, and there was much anger. The whole of scientific research was full of secret plots, heresies, and bombs—against God.

There was a most appalling illustration of this in the Scientific Congress, held in September, 1863. Nothing is more amusing to-day than to run through the yellow and almost unknown papers of the Congress. They are illuminating to some extent. An idea that belongs to humanity is openly brought into the debate for the first time. Ages lie behind this hour. We must grant all that savours of human comedy, of triviality even, in such an assembly, but after all we must see in it the swell and clash of great waves. Haeckel spoke for the first time on Darwin’s theory, at a spot from which the waves were bound to spread through the whole scientific culture of the land. Virchow, afterwards his bitter opponent, supported him. All the deepest questions and consequences of Darwinism were mooted with the first vibrant accents. It was a great and unforgettable hour.

The first speaker at the Congress on the Sunday evening, September 19, 1863, was Haeckel. We must remember the charm that attached to his person even outwardly, the direct charm that did not need any allusion to his growing repute in zoology. It was the charm that had been felt by the simple folk of uncultured Italy, who had never heard even the name of the science. Darwin was never a handsome man from the æsthetic point of view. When he wanted to sail with FitzRoy, it was a very near question whether the splenetic captain would not reject him because he did not like his nose. His forehead had so striking a curve that Lombroso, the expert, could put him down as having “the idiot-physiognomy” in his Genius and Insanity. At the time when he wrote the Origin of Species he had not the patriarchal beard that is inseparable from his image in our minds; he was bald, and his chin clean shaved. The prematurely bent form of the invalid could never have had much effect in such a place, no matter what respect was felt for him. Haeckel, young and handsome, was an embodiment of the mens sana in corpore sano. He rose above the grey heads of science, as the type of the young, fresh, brilliant generation. It was an opponent at this Congress, who sharply attacked the new ideas, that spoke of the “colleague in the freshness of youth” who had brought forward the subject. He brought with him the highest thing that a new idea can associate with: the breath of a new generation, of a youth that greets all new ideas with a smiling courage. Behind this was the thought of Darwin himself, a wave that swept away all dams.

The speech was as clear as crystal, and is still useful as an introduction to the Darwinian question. He at once strikes the greatest and the dominant note. Darwin means a new philosophy. All organisms descend from a few primitive forms, possibly from one; and man is one of these organisms. What Darwin had merely hinted in his concluding passage, what the aged Bronn had excluded altogether from his translation as too dangerous, was now set forth emphatically in the very beginning of his speech. “As regards man himself, if we are consistent we must recognise his immediate ancestors in ape-like mammals; earlier still in kangaroo-like marsupials; beyond these, in the secondary period, in lizard-like reptiles; and finally, at a yet earlier stage, the primary period, in lowly organised fishes.”

There is something monumental in this passage, as in the previous confession of Darwinism in the Monograph on the Radiolaria. Others may have come to similar conclusions at the time on reading Darwin’s work. Here we have the profession made at the psychological moment, a trumpet-blast that sent its thrilling alarm from the threshold of a new age, for friend or foe to hear. The speech gives a slightly exaggerated account of the struggle that already existed. All was in confusion. Science was breaking up into two camps. On the one side evolution and progress, on the other the creation and immutability of species. Already there are distinguished leaders of science in favour of evolution. It is time to discuss the matter in full publicity—and the thing is done.

There was, let me say parenthetically, on the Continent at least no question at that time of this clear division, or even of a serious agitation. It was partly this speech, together with Haeckel’s next work, that was to bring it about. To the highest authorities the subject seemed to be below the level of discussion. We must recall a passage that the Professor of Zoology at Göttingen, Keferstein, had written a year before in the Göttinger Gelehrte Anzeiger. “It gives great satisfaction to the earnest scientific worker,” we read, “to see a man like Agassiz, with an authority based on the finest zoological works, reject unreservedly a theory [Darwin’s] that would discredit the whole work of classifiers for a century, and to see that the views built up by several generations and the general consent of humanity hold a stronger position than the views of a single individual, however eloquently they may be stated.” There is no idea in this of two regular camps of scientists. Humanity is adduced as the one party; against it stands the anarchist, trying to blow up the work of centuries, Darwin. But that gave no concern to the young orator; he saw a whole decade of success in the first attack.

He rolled off geology. Cuvier’s theory of catastrophes, Linné’s belief in the immutability of species—all a purely theological cosmogony. The “philosophical theory of evolution” rises behind it like a Mene Tekel Pharshim.

All living things, including those of past geological epochs, form one great genealogical tree. The word, the new leading word for zoology and botany, comes out with a flash. What is the system that has been awaited so long? It is the genealogical tree of life on our planet. Its roots lie deep in the remote past. “The thousands of green leaves on the tree that clothe the younger and fresher twigs, and differ in their height and breadth from the trunk, correspond to the living species of animals and plants; these are the more advanced, the further they are removed from the primeval stem. The withered and faded leaves, that we see on the older and dead twigs, represent the many extinct species that dwelt on the earth in earlier geological ages, and come closer to the primeval simple stem-form, the more remote they are from us.”

This was the great new idea for science to work upon. Paleontology, the science of past life, found at last a common task with botany and zoology. Haeckel’s own programme for decades was unfolded. This phrase, too, was a birth-hour. In all the struggle that has followed as to the “how” of evolution this figure of the tree with the verdant branches as the new field of zoological and botanical work, and the withered branches for the paleontologist, has never been abandoned. A symbol from the living world itself, the branching tree, had at last taken a decisive place in the science and the classification of living things. With splendid clearness the speech then enumerates the Darwinian principles: variation, heredity, the struggle for life, selection, and adaptation. A vast duration is claimed for the geological epochs in the sense of Lyell; and it is pointed out that there is a progressive advance of forms throughout these periods. Special stress is laid on the ever-advancing, ever-uplifting element in evolution. Man is again introduced into the subject. He has “evolved” from the brutality of the animal. Language itself has been naturally “developed.” (What a shrewd perspective in such a brief phrase! How the philologists would stare!) So the “law of advance” traverses the whole field of culture. A fiery passage follows: “Reaction in political, social, moral, and scientific life, such as the selfish efforts of priests and despots have brought about at every period of history,” cannot permanently hinder this advance. The “advance” is “a law of nature,” and “neither the weapons of the tyrant nor the anathemas of the priest can ever suppress it.” We hear again the older Sethe thundering his intrepid reply: “You will have to shoot the law first.”

At the close he glances briefly at the difficulties the theory presents. We must regard even the first beginnings of life as the outcome of “evolution.” Naturally. Darwin’s God has no use for this prophet. But how shall we conceive it? Was the thing that first developed from the inorganic “a simple cell, such a being as those that now exist in such numbers as independent beings on the ambiguous frontier of the animal and vegetal worlds?” Or was it a particle of plasm merely, “like certain amœboid organisms that do not seem to have attained yet the organisation of a cell”? Again the simple question contained a whole programme.

Schleiden had first shown in 1838 that the body of any plant can be dissolved into tiny living corpuscles, which he called “cells,” because they often had the appearance of a filled honeycomb. A year later Schwann proved, in Johannes Müller’s laboratory, that the higher animal also is a product of these cells. The cell was recognised as the living unit that composed the oak and the rose, the elephant and the worm. Man himself, in fine, was but a pyramid of these cells—or, to speak more accurately (as each cell has its own life), an immense community of cells, a cell-state.

Virchow had, as we saw, laid the greatest stress on this last and most important deduction from the cell-theory a short time before. He looked upon every individual man as a mysterious plurality—a plurality of cells. Pathology, the science of disease, must take account of this. Health was the harmonious co-operation of the cell-state; disease was the falling-away of some of the cells to special work that injured or destroyed the whole community. This conception had inaugurated a new epoch in medicine, making it a consciously ministering art in the service of the living human natural organism. The Darwinian had now the task of showing the validity of this conception in his own province. The genealogical tree of the animals and plants must at once be drawn up in the form of a genealogical tree of the cell. The cells had combined to form higher and higher communities, and each higher species of animal or plant was in reality one of these social constructions. But this complexity was only found in the upper branches. The lower we descend, the simpler we find organisms. The lowest forms of life represent cruder, simpler, and more primitive cell-structures. And the final conclusion was that all the cell-communities or states must have been evolved from unattached individuals whose whole body consisted of a single cell. We cannot strictly call these lowest forms of life either animals or plants; they can only be likened to the single cell. Though Haeckel himself did not know it at the time, all his pretty radiolaria at Messina belonged to this category. The whole swarm of bacilli and bacteria fell into this world of the “unicellulars.” Haeckel’s words threw a brilliant light on the question. Not only the simplest forms of life are unicellulars; the primitive forms also were. With them began the colossal genealogical tree that branches out through the millions of years of the earth’s history. If anything on the earth has arisen by spontaneous generation out of dead matter, at the commencement of all life, it must have been a cell, or a still simpler particle of living plasm more or less resembling one. It is true that the point is put in the form of a question; but the veil has been torn away. Given one cell, the whole genealogical tree grows on, in virtue of Darwin’s laws, until it reaches its highest point in man.

The conclusion of the speech greets Darwin as the Newton of the organic world, a phrase that has often been repeated since.

Let us turn over a few pages more in the faded record of the sitting. Fourteen years later he would speak again at a scientific congress, and speak on Darwinism. He would then put it forward no longer as a hope but a fulfilment, of which he showed one glittering facet. And no other than Rudolf Virchow, his former teacher, would oppose him and deliver his famous speech on the freedom of science in the modern State and its abuse by Darwin’s followers. This was at Munich in 1877. The least of his hearers would remember that Virchow had spoken, like Haeckel, at Stettin fourteen years previously. But we must understand the thirty-sixth speech if we are to understand the thirty-seventh.

It was the second sitting, on September 22nd. Virchow spoke on “the alleged materialism of modern science.” The subject was not provoked by Haeckel, but by Schleiden, the botanist, the parent of the cell-theory. The controversy over materialism had raged furiously for many years. We need only mention Büchner (whose Force and Matter appeared in 1855) and Carl Vogt. There was an element of necessity, but a good deal of superficiality in the controversy, as it was then conducted. Friedrich Albert Lange has given us a masterly history of it. At this moment it was particularly instructive to point out the difference between general philosophical skirmishing with words and a really able piece of work that, though it had a technical look, suddenly added a new province to philosophy on which every doubting Thomas could lay his hands. However, Schleiden had not advanced. Curiously enough, he, the first discoverer of the cell, attacked Virchow’s theory of man as a cell-state as a typical materialist extravagance.

He had published a heated essay, and Virchow defended himself. He gave such a remarkable and characteristic expression of his inmost feelings that it is worth while disinterring it. It is a very rare thing for a thoughtful man to give a natural-philosophical speech that begins with crystalline clearness of logic and then makes a most curious salto mortale at the critical point.

He opens with a vigorous protest that there can be no quarrel about the materialism of science with the “spiritual” and the “privately-orthodox.” Such people must regard all investigation of “this world” as aimless. The only thing of value for them is “the next world”; the best attitude towards this life is as crass an ignorance as possible, and so all science is worthless. The words are so sharp that he was interrupted and had to explain that he was not attacking anybody personally. He was only speaking “with the candour of a scientific worker, who is in the habit of calling things by their proper names.” (At this point there was some applause.) Hence he is not speaking of materialism, he says, on that account, but because of certain objections from men of science, who said that philosophic speculation led us out of our way. Schleiden had branded the theory of man as a cell-state, the conception of man as, not an absolute, but a federal unity, as materialism. But this conception is not a philosophical theory at all; it is a fact. It is a piece of scientific truth, like the law of gravitation. He recurred to the old and often-quoted definition: the kind of research that brings such facts to light has nothing whatever to do with philosophy. On the other hand, “materialism,” in so far as it expresses a general theory of the world, is a philosophy. Hence the simple investigation of facts as such can neither be dubbed materialistic nor said to have a philosophic tinge.

There are many objections to this strict delimitation of the provinces of the human mind, as Virchow lays it down in the old style. It is true that materialism is a real philosophy, especially in the form current at the time and given to it by Vogt and Büchner. But it is a question whether we see, observe, or investigate at all, if we completely exclude philosophy; whether the philosophic thought can be really pumped out of even the most rigorous and exact “observation of facts,” like air in the air-pump; whether there are any such things as purely objective “facts” in this sense in any human brain. And it is also a question whether the facts, however objectively we regard them, do not arrange themselves, when they are numerous, in logical series, which force us to draw conclusions as to the unknown by the very laws of probability; in other words, whether they do not always produce a “philosophy” in the long run. However, these questions are all well within the pure atmosphere of science. It is Virchow’s practical conclusions that are interesting; and he goes on to draw them freely.

The man of science gives us no dogmatic philosophy of any kind, but facts. But for these facts and for the research that leads to them he must have an absolutely free path. No power can legitimately stand in his way that does not offer him more of what he regards as his palladium—facts. And, curiously enough, when we think of later events, the illustration that Virchow takes in 1863 to enforce this is—the Darwinism that Haeckel had just put before them.

Haeckel and Virchow were friendly colleagues at the time. We have already said that Haeckel was Virchow’s assistant at Würtzburg. Not only as a man, but especially as a scientist, Virchow was then (and long afterwards) greatly admired by him. The idea of the cell-state got into his blood; it was one of the bases on which he built up the Darwinian theory. Though he had never recognised this distinction between the mere investigation of facts and philosophic reflection on them, he respected Virchow as a master of methodological education. What was “method” at the bottom but philosophy! Was not the method that expressly excluded “miracles,” that sought always the natural law and the causal connection and the continuous series, a “philosophy”? This was the only method taught under Virchow as long as Haeckel worked with him. At the time the divergence of their ideas was not shown more openly. The one called “philosophy” what the other said was “the purely objective method of investigating the truth.” The figure of Pilate rises up behind the dilemma with his question: “What is truth?”

However, Virchow takes Darwinism by way of an example of which he approves, a point that seems to be established in the province of pure facts. In the Munich speech of 1877 there are polite references to “Herr Haeckel.” “As Herr Haeckel says.” “As Herr Haeckel supposes.” At Stettin we find Herr Haeckel described as “my friend Haeckel,” with whom “I quite agree,” &c. Haeckel himself, by the way, was still convinced—in his essay On the Generation of Waves in Living Particles—two years before the schismatic Council of 1877 that Virchow had had a decisive influence on his own Darwinian career. “If I have contributed anything myself in an elementary way to the building-up of the idea of evolution, I owe it for the most part to the cellular-biological views with which Virchow’s teaching penetrated me twenty years ago.” “As Herr Haeckel supposes,” was the cool repayment of this sincere expression of gratitude. However, that is another matter. Let us return to Stettin. We read, where “my friend Haeckel” comes in, that he has shown how scientific research (the pure investigation of facts without the least tincture of philosophy) has gone on to deal with “the great question of the creation of man.” It is merely conceded that there are still certain small outstanding difficulties, as, for instance, at the root of the genealogical tree. According to Darwin it is conceivable that there were four or five primitive forms of life. Haeckel is inclined to restrict them to a single stem-cell. It seems to him (Virchow) that there may have been a number of different beginnings of life. We have here the opening of the controversy as to the monophyletic (from one root only) or polyphyletic (from several roots) development of life, which is still unsettled as far as the commencement of life is concerned, but a very secondary question. It would be well if there had never been any more serious difference between Haeckel and Virchow. The speaker himself thinks it an unimportant matter beside the great question of freedom for scientific inquiry. One thing is as clear to him as it is to Haeckel. The biblical dogma of creation has broken down. It is impossible to take seriously any longer the breathing of the breath of life into a lump of clay, if these Darwinian ideas are sound. Once it is fully proved that man descends from the ape, “no tradition in the world will ever suppress the fact.” Scientific inquiry alone can correct itself. And what it holds to be established must be respected beyond its frontiers as well. What does he mean by “beyond its frontiers”? He means, as he makes it clear here, the same as Haeckel himself. “Church and State,” he says, must “reconcile themselves to the fact that with the advance of science certain changes are bound to take place in the general ideas and beliefs from which we build up our highest conceptions, and that no impediment must be put in the way of these changes; in fact, the far-seeing Government and the open-minded Church will always assimilate these advancing and developing ideas and make them fruitful.” What more do we want?

If this were the conclusion of Virchow’s speech, it would be merely a confirmation of Haeckel’s—the kind of support that the older worker can give to ardent youth, though on different grounds. But the cloven foot has still to peep out. I believe that, in the pure struggle of ideas, we can determine here, in 1863, precisely the point where Virchow falls—falls into a line that has nothing in common with the ideal struggle of the really free and liberating thought of humanity. We come to the great salto mortale, which one must see from 1863 onward in order to understand the Virchow of 1877.

The passage is the more interesting as it refers to one of the chief stages in the development of Haeckel’s mind. The conception of man as a cell-state, established by Virchow in so masterly a fashion, involved a very curious conclusion. This conclusion, however we take it, came so close to the roots of every philosophy that it justified Schleiden to some extent when he protested that the whole cell-state theory was a philosophical element.

If the human body is composed of millions of cells; if all the processes and functions, the whole life of the body in Virchow’s sense, are merely the sum of the vital processes and functions of these millions of individual cells; is not what we call “the soul” really the product of the millions upon millions of separate souls of these cells? Is not man’s soul merely the state-soul, the general spirit of this gigantic complex of tiny cell-souls? The lowest living things we spoke of, which consist of a single cell, showed unmistakable signs of having a psychic life. There was nothing to prevent us from thinking that in the combination of these various cells into communities each of them brought with it its little psychic individuality. And just as the individual bodies of the cells combined externally to form the new individual of the human body, so the cell-souls would enter into a spiritual combination to form the new psychic individuality of the human mind. I say there was nothing to prevent us from thinking this, in the line of deductions from the plain principles of the cell-state theory which Virchow claimed to be a naked “fact.” Philosophically, however, an immense number of questions, problems, doubts, and hopes lurked behind it. The whole conception of individuality took on a new aspect. First, in the material sense; the individual human being seemed to be, bodily, only the connecting bracket, as it were, of countless deeper individuals, the cells. But it was more significant on the spiritual side. The individual human soul could be analysed into millions of smaller psychic individualities, the cell-souls, of which it was the sum. The unified ego, the consciousness of self and unity of the psychic clamp, “man,” remained as the connection of all the cell-souls. A ray of light was thrown on the deep mystery of the origin of individualities, material and spiritual. Haeckel devoted himself afterwards to the question with all his energy. But at the time it was Virchow who, unconsciously enough, started the great wave that welled up from the depths of his theory.

He had marked out his path very clearly in the first part of his speech. Scientific research collects facts. It puts them before us without any reference to philosophy. The less philosophy there is in the investigation of facts the better. But the other side of the matter is that no power in heaven or on earth has anything to say as regards its work on things that it holds to be facts. The only possible logical conclusion from this, with reference to the question of the cell-soul, was for the investigator of facts to say: Even in respect of the psychic life we go our way and look neither to right nor left, whatever conclusions and assumptions the philosopher makes. Virchow acted very differently.

He first grants that this dissolution of man into a federal unity of countless cells must somehow affect the “unified soul.” We are compelled “to set up a plurality even in the psychic life.” He has reached the limit of his radicalism. We expect him to continue: Hence, as in the case of the Mosaic story of creation, of Darwinism, of the cell-theory as a whole, so here we men of science go our way unmoved; even if the whole of the teaching that has hitherto prevailed in philosophy and theology in regard to the soul breaks down, we simply go our way, and do not ask anybody’s permission. This he does not do. Take one step further, he says, and we “can easily believe that it is necessary to split up our whole psychic life in this way and ascribe a soul to each individual cell.” Haeckel believed a little later that this was necessary; that the most rigorous logic compelled us to do it. But, says Virchow suddenly, we must protest most vigorously against this. This deduction from the cell-state theory reaches a point where “science is incompetent,” namely, “the facts of consciousness.” Taboo! The path of the scientific inquirer is barricaded. What follows rests on no scientific grounds, but is a sort of confession. Up to the present natural science has not been able to say anything as to the real nature, the locality, and the ground of consciousness. “Hence I have always said that it is wrong to refuse to recognise the peculiar character of these facts of consciousness that dominate our whole higher life, and to yield to the personal craving to bring these facts of consciousness into accord with an independent soul, a spiritual force, and let the individual formulate his religious feeling according to his conscience and disposition. That is, I think, the point where science makes its compromise with the Churches, recognising that this is a province that each can survey as he will, either putting his own interpretation on it or accepting the traditional ideas; and it must be sacred to others.” The direction of the logic is clear enough. The application of the cell-state theory to psychic life must lead to the problem of consciousness. But we must not follow it, because science has never yet penetrated into this province. It is the province of peaceful compromise with “the Church,” and we must respect it.

It seems to me that the explanation is clear. The whole field of conflict that Haeckel found within the science of his time is opened out, though Virchow was by no means disposed at that time to take Darwinism as an example of the thing to be avoided, as he did at Munich fourteen years afterwards. The kind of scientific inquiry that Virchow advocated is what was called “exact” at a later period. It kept clear of all philosophical speculation, and repeated over and over again that it was only concerned with facts. It had, however, another card to play—peace with “the Churches.”

Philosophy was shunned in order to leave a free field for the Churches to build in. Then the exact scientist took his hat and said, I am afraid I am incompetent, and the philosopher is incompetent, to do anything here; let the Church take the vacant chair, with my compliments. No philosophy: on this we will make war to the knife. This is “a point where science makes its compromise with the Churches.” No one can understand Haeckel’s career who does not grasp this antithesis. The contrast between Haeckel and Virchow, known to all the world since 1877, is clearly indicated. Virchow’s speech in 1877 is obscure. We must go back to 1863 to get behind the veil—the veil that hides Virchow, that is to say, the most prominent representative of the hostility to Haeckel. We cannot understand otherwise how this yawning gulf came about between Haeckel’s ideas and a school that professed to follow “exact” research. Haeckel was building up a natural philosophy which, starting from the solid foundation of scientific research and its results, went on to further, and greater, and more far-reaching issues, that could not be seen, but could be reached philosophically by more or less happy deductions from the scientific data. It might or might not have lasting value in points of detail. He was subject to the law of evolution. He worked with analogy, and the things he compared thereto were ever changing. It was all the same to him. In any case the dawning glimmer of the perfect light broadened out and lit up vague outlines even in the cloud-wreathed unknown. The others worked in such a way as to leave beside them provinces of a virgin whiteness, untouched by thought or logic. At times they slipped into these provinces, and celebrated their reconciliation-festival with “the Churches.” The layman continued to think that the Churches wielded an absolute authority; that the scientist, abandoning his natural philosophy, came to pay them tribute. This situation has done infinite mischief, more than the wildest and even obviously perverse philosophy ever did. It put the scientist in the position of a tolerated vassal in the world of thought—the world that the Churches had held in chains for ages. Woe to the man who ventured to discuss “consciousness”! Not because science had but the slender proportions of a pioneer in that field, and because there was a danger of it making great mistakes with its natural philosophy. No, but because the white neutral field began here that we had agreed to respect—we “exact” scientists and “the Churches.” This was the real reason why Virchow and so many others who advocated the strict investigation of facts had forfeited the right to oppose Haeckel’s bolder natural philosophy and its conclusion—will have forfeited the right, at least, in the judgment of a future and more impartial generation. They did not oppose him on the lines of an equal zeal for the truth, but on much lower and reactionary lines. Their concern was not for the absolute triumph of truth, but for a compromise with certain forces in public life whose supremacy was not grounded on logic but on inherited external power. It required a certain amount of diplomatic shrewdness to enter into this compromise, in view of the practical power of those forces. Haeckel never had this “shrewdness.” We grant that. But it is certainly a confusion of all standards when the shrewdness of the individual tries to entrench itself behind ostensible claims of scientific method; when research abandons all advance on certain sides on the plea of “exactness” instead of philosophising—and then itself makes use of this exactness for compromising with an ecclesiastical tradition that only differs from real philosophy in its antiquity and rigidity, its disdain of rational argument, and its employment of secular weapons that certain historical events have put in its hand without any merit on its own part.

The darkest cloud that hung menacingly on the horizon of Darwinism came from this quarter. At the moment we are dealing with it did not cause much concern. This early Darwinism thrilled with optimism as with the magic of spring. Haeckel had to speak once more in the course of the Congress. The geologist, Otto Volger, made a polite but energetic protest against the new theory in the final sitting. It was a curious connection of things that brought Volger into such a position.

Volger is the man who saved for Germany the venerable Goethe-house at Frankfort-on-the-Main. The Free German Chapter received it from him as a gift. The action has nothing to do with geology, but it stands in the annals of culture. Thus the shadow of Goethe came to Stettin, to be present at the open birth of German Darwinism—Goethe, who had once stood on the very brink of the evolutionary ideas. And the man who brought him was a geologist who felt moved to attack the ideas of Darwin and Haeckel!

No part of science became in the succeeding decades so fruitful for Darwinistic purposes as geology. It might very well be called a continuous argument for Darwin; from the little slab of Solenhofen Jurassic schist that yielded, in 1861, the first impression of the archeopteryx, the real connecting link between the lizard and the bird, to the incomparable discoveries of Othniel Marsh, Cope, and Ameghino in America, which put whole sections of the genealogical tree of the mammals before us, on to the skull and thighbone of the ape-man (pithecanthropus) of Java, found by Eugen Dubois, which brings so vividly home to us the transition from the gibbon to man. But, as if it had been scared away by the new idea of evolution and its demand for proof, the most and the best of this material was not forthcoming until after Darwin was pretty firmly established everywhere. At the earlier date we are dealing with it was quite possible for a geologist to play the sceptic with a shadow of justification. We need not go into the point to-day. It is ancient history. But there is an incidental point in Volger’s criticism and the reply it provoked from Haeckel that calls for notice.

Volger declared that Darwinism in general was an unsupported hypothesis, but he made a concession. The species of animals and plants need not be absolutely unchangeable. The only thing that is impossible is a continuous upward direction in evolution. All the groups of living things, even the highest, may have been present together from the earliest days. Local changes in the distribution of land and water, &c., must have brought about a certain amount of variation in life-forms. But after brief divergences all would return to the original type. The proper symbol of the story of life is the wave that rises out of the sea and sinks back into it. There was no such thing as a steady advance, a wave that never sank back into the water. The real image of human life is the analogy of its obvious development: youth, maturity, then old age and back once more. The speaker urged in plausible terms that this conception retained the idea of an “eternal becoming,” which is better than a rigid fulfilment. As if an eternally advancing evolution did not include this “eternal becoming.” Haeckel spoke immediately after Volger. He not only attacked the weak points of the geologist, but went on to the deeper philosophic question. The notion of a “perennial circular movement” is “inconsistent with all the facts of human history.” “If we appeal to sentiment, I must say that this circular theory has no attraction for me, whereas the Darwinian idea of a progressive evolution seems the only one consistent with the nature of man.” The story of the animals and plants is subject to “the law of progress” just as much as human history.

In these words of Haeckel’s we have a clear indication of the optimistic temper of Darwinism at the time. They touch a question of fundamental importance for the value of the new theory: the question whether, in spite of all it destroyed, in spite of its disseverance from the idea of God, it brought with it a new ground of conciliation, a conviction of the ever-advancing growth of the world and ever greater achievements? God was replaced by natural law. There was no longer any “design” beyond the simple and unchanging course of natural laws. Well, what were these natural laws going to do for us? Were they giving us a world that would become more and more harmonious, that was on the whole an advancing organism, that would be an increasing embodiment of God—the God within nature, not without, God at the end of things, after æons of worlds that seemed to break up like the individual in the struggle for existence, yet were eternal in the mighty essence that was tossed on from world to world like a grain of dust and was made the starting-point of infinitely new and more complex movements? Or—was the work of these natural laws but a ceaseless poking and thrusting and bubble-blowing without any inner meaning? Was it the play of waves that rise and fall, and rise and fall again, in the ocean, an eternal melting into smoke and nothingness? Was the whole of “evolution” an absolutely meaningless play of innumerable tendencies, not one of which would ever come to anything?

This note also was found in the first melody. Something would have been lacking if it had not been struck. Here again there could be a parting of ways, not only in the crowd, but amongst the thoughtful. The whole struggle of optimism and pessimism might be dragged in. At all events, the problem was bound to be pointed out from the start.

When Volger, not a bad opponent at the bottom, and Haeckel had made their speeches, indicating at once certain lasting antitheses within the subtle philosophy of Darwinism, Virchow closes the debates and the Congress with a most dangerous blessing. In essentials he is once more on the side of Haeckel. He suggests that geology should be allowed to mature a little before final judgment is passed. The strongest evidence for evolution is found in embryology (the science of the embryonic forms and uterine development of living species of animals). The prophecy was fulfilled, if ever prophecy was, and in Haeckel’s own most particular field of work. But, in fine—he returns to his point—the main thing is the “pursuit of truth.” And since “the most earnest ecclesiastical teachers” declared that “God is truth,” he could not do better than close with a reminder (I quote him verbatim) of “the compromise that may be effected between science and the Church.” Translated into plain language, that means: My dear children, fight it out as you will, but respect the Church always as the main thing, and you will do well, however much you differ. Thus closed this remarkable Scientific Congress—as quietly as a bomb that smokes noiselessly, like a whiff from a tobacco pipe. But one day it will burst.