The History of Biological Theories

In Germany the first discussion of the theory took place early in 1860. In the same year Darwin's book was translated into German by Professor Bronn. The trans- lator's attitude to the theory of the English scientist was significant. Bronn was no Darwinian, but translated the book out of a sense of duty, believing so interesting a work should be familiar in his own country. For reasons already known to us, Darwin only just hinted in his book that his theory was also applicable to Man. Without giving a reason Bronn omitted this reference. That it should not be thought that he wished to testify to his belief in these theories, Bronn added an appendix in which he criticized the views expressed by Darwin.

Bronn's conclusion is extremely characteristic. Having shown why he cannot accept Darwin's theory, and after indicating many objections, he adds that ' It is true that even more formidable objections can also be brought against the ordinary theories of Creation, but they are totally different in kind. Creation, being itself supernatural, is not necessarily capable of a natural explanation. It is miraculous and without parallel. It therefore seems to us more logical to retain the old, unscientific explanation. . . . For,' he continues, 'many scientists will adopt the new ideas, and from this conflict of opinion the truth will finally emerge' (Entstehung der Arten^ ilbers. von ronn,p. 518).

This first presentation of Darwin's work was, however, to undergo correction. Bronn's translation was politely ignored and a new and complete one by Carus was pub- lished, which raised no such objections. Bronn's peculiar point of view was by no means an isolated one ; later it appeared again and exerted a much more lasting influence. To understand the fate of Darwin- ism in Germany we must, however, look back a little. In the forties there had been very great rivalry in Germany between philosophy and the exact sciences. This really represented a conflict between the aristocratic and the democratic ideal. Philosophy, the queen of the sciences, was in its presentation aristocratic. Philosophers thought that by purely intellectual processes they could deduce general laws for the sciences and for ethics. Hegel considered that philosophical wisdom should dominate the intellectual world. This worship of the intellectual and despising of the practical, this contrasting of the average with the exceptional, is the essence of the aristocratic point of view. The philosophers shared the advantages and defects of that way of thought. They readily attached themselves to the Church and to the temporal powers.

Democratic views were introduced into German science by Vogt, Moleschott, Virchow, and Biichner. They held that knowledge should have its roots in the common life of the people, and should be of practical use. In contrast with most of the philosophers they wrote in an easy style and for the general public, and they spoke disparagingly of philosophy, of the soul, of government, and of other 'un- practical 5 things. Moleschott's demand that cemeteries should be used for agriculture, since they are such well- manured fields, serves to show the line of thought of these democrats. Moleschott was well known for the eloquence and sincerity of his style.

Vogt introduced into German popular science the style called by the French 'causerie', by the Germans Tlauderei.' Virchow spoke and wrote in a familiar style and was a strong political liberal. Biichner was prosecuted because of the alleged immorality of his book Kraft und Staff. Vogt was obliged to flee to Switzerland before the forces of political reaction. Moleschott, reprimanded by the Senate of the University of Heidelberg, resigned his post and migrated to Italy. Virchow was dismissed from his professorship in Berlin, though subsequently reinstated. Such was the state of ferment in the German scientific world when Darwinism burst upon it.

The older scientists, who were also philosophers, re- jected the new teaching with indignation, regarding it as an attack on their aristocratic principles. Some became abusive Burmeister, for example, who strongly objected to the theory connecting the monkey with man ; Giebel, the zoologist, declared the teaching 'a chaos of unproved and unprovable impertinences' ; Ehrenberg adversely criticized parts of the theory in detail, and then declared the whole to be a 'sick man's fancy', or, at best, an 'interest- ing romance'. Schimper, the botanist, called it 'the most short-sighted, the stupidest and most brutal theory imaginable, with which a modern buffoon and bearer of false witness could seek to make himself interesting' ! The ethnologist Bastian wrote that it was 'an example of mental laziness which had caused a mere stubborn avoid- ance of the tremendous range of the problems requiring solution'. Fraas, the geologist, declared that the hypo- thesis of the evolution of Man from an orang 'belonged to that mythological realm where dwells the unicorn'. The theory received equally definite though more mildly expressed criticism from other scientists : Wagner the physiologist, Goeppert the geologist, the embryologists von Baer and Kolliker, Leydig the zoologist, Braun the botanist, and others.

The scientists belonging to the democratic school, on the other hand, welcomed a theory founded on the axioms of John Stuart Mill. Schleiden, although he really represented an older school of thought, was one of the first to accept the new teaching, but he did not publish his reasons for acceptance. Vogt was also a convert. He had previously rejected the idea that animal forms may under- go modification, and had found himself unable to accept Lamarck's views. He had agreed with von Baer, the embryologist, in opposing the embryological fancies of Meckel and Serres, in which he could see nothing more than a repetition of the hated 'Naturphilosophie' ; and he had been a strong supporter of the belief that the varying forms of life were created as they exist without any Divine intervention. Now he became a convert to Darwinism, although he never completely freed himself from the in- fluence of Cuvier's catastrophic theories. Ludwig Biichner now began to teach his ideas about 'Kraft und Stoff' with increased zeal, declaring that man is nothing but a superior monkey. Strauss shared these views. Virchow, too, accepted the theory of Natural Selection, hoping 'that it will be of practical use in every-day life. Its importance for our philosophic and ethical views cannot be over-estimated, since it pictures for us how progress in Time is possible'.

The more moderate followers of the new scientific tendencies also gave their approval to Darwin's work. Du Bois Reymond welcomed it joyfully, calling Darwin the 'Copernicus' of the organic world. He pointed out that this new theory explained the occurrence of those innate ideas about which Leibnitz and Locke had argued; on the Darwinian theory they would be due to inheritance. Helmholtz was convinced that Darwin had succeeded in explaining why each organism is suited for its purpose. In his Geschichte des Materialismus Lange completely accepted Darwin's views, and defended them against the criticisms of philosophers. Fechner never freed himself entirely from his older philosophical ideals; but he en- deavoured by means of the Darwinian theory to reconcile the two divergent theories of uncontrolled atomic motion, on the one hand, and of an orderly world on the other. He formulated an hypothesis which he called the 'Tendency to Stability', suggesting that the whole universe was originally lawless, and that it is gradually developing towards a more tranquil condition of law and order.

These scientific democrats Vogt, Virchow, du Bois Reymond, von Helmholtz thought that they had done their duty to the new theory in giving it a friendly re- ception. They assumed that it would now be discussed in university lectures, would become the subject of learned and of popular treatises in short, would go the way of all scholastic theories. But in Haeckel's hands the teach- ing assumed a somewhat dangerous form. His views will be treated more fully later : here enough must be said to make the connexions clear.

Haeckel was formerly the pupil and then the assistant of Virchow. In his later years he often used to tell with what enthusiasm he followed the materialistic lectures ('monistic', Haeckel would call them) of his master. The same lectures stimulated Biichner to write his Kraft und Stoff. The ideas of Darwin now became linked up in Haeckel's mind with the teaching of Virchow, and he devoted his whole attention to these matters. He accepted with enthusiasm the idea that nothing exists save atoms and their motions. He was sure that Man has descended from the ape. Since these things are true, they must, he held, be generally accepted, and the whole of human life must be ordered in compliance therewith. Haeckel soon began to teach openly that 'the greatest triumph of the human spirit, which is the recognition of Nature's most fundamental laws, must not remain the private property of a privileged intellectual class, but must become the common property of all mankind'.

Haeckel's challenge awakened considerable response. Philosophers, filled with enthusiasm for the theory, and convinced of its truth and importance, gave it publicity by lectures, books, and newspaper articles. Jaeger, Seidlitz, Dodel, Dumont, Biichner, Schmidt, Krause, von Hell- wald, Preyer, Rolle, and others became the heralds of Darwinism in Germany. In 1871 Hellwald became the editor of Das Ausland, a paper in which geographical articles were published ; and this journal now became an exponent of the Darwinian theory. Krause started Kosmos in 1877 for the sole pur- pose of spreading the new ideas. The proclaimers of the

theory were extremely active. Among them were not only such radicals of the University world as Professors Haeckel (Jena), Schmidt (Strasbourg), Preyer (Jena), &c., but also many non-academic men, as Carneri, Dumont, v. Hellwald, Biichner, Krause, Du Prel, F. Miiller, R. Miiller, Rolle, and others. The scientific work of these men was very unequal in value, but it would be unjust to them to compare them with the 'popular' writers and lecturers of to-day, who merely express well-worn plati- tudes in new words. Their work bears evidence of deep sincerity and of a conviction that they are dealing with matters of fundamental importance. This sincerity is very remarkable in books obviously not the productions of first- class minds. Some (e.g. Seidlitz, Schmidt, Carneri) made an earnest attempt to understand the old teaching and to show in what respects it was being supplanted by the new. Others (e.g. Preyer, du Prel, Jaeger) used the theory to develop really new ideas. Others again (e.g. the brothers Miiller) spent their time collecting facts in support of the theory.

Anti-Darwinian literature increased in a similar manner. Special supplements, poems, jokes, novels, caricatures, sermons, 'open letters' both scientific and unscientific, and popular books overwhelmed the market. The flood of Darwinian literature was unstemmed. The spirit of the times, with its ever-increasing material- ism and radicalism, was an important factor leading to the general acceptance of the theory. The rising generation saw in the new teaching the only truth. Its opponents were to them mere reactionaries. The younger men heard the conservative teachers still speaking of the 'spirit' in Nature, of the 'thoughts' embodied by each animal type, of the 'mystery' of Creation. The constant repeti- tion of these phrases led the pupils to think that philosophy consisted of mere words, that its day was over, and that nothing new was ever again to be produced by it.

The personal weaknesses of the older teachers also played their part in the controversy. Pedantry, bumptious- ness, exaggerated ideas of the importance of their own works afi these faults were, as always, but too apparent to the young. In disputes as to the truth of new opinions the old are always at a disadvantage ; age signifies reality ; youth potentiality. Youth carries the day by its eager hopefulness ; age damps expectation. The words of Clau- dius, quoted by Tacitus, still hold good : 'Omnia patres con- scripti, quae nunc vetustissima creduntur, nova fuere.'

Let us see, from some examples, how these Darwinists despised their teachers. 'It happens by chance that I have known your Leipzig biologists personally for a long time, and can well imagine how these very exact investigators despise your speculative aberrations that learned man, Leuckart, whose knowledge of zoology is as great as his understanding of it is superficial ; the dull uninspired Schenk, who frightened me off botany in my student days ; that industrious workman, His, whose industry as a student was only equalled by his narrowness* (the letter appeared as a supplement to Zollner's Uber die Natur der Kometen, Leipzig, 1883).

The same thing was happening in England. Huxley wrote to his friend Hooker about Owen, whom Huxley himself had called 'England's greatest anatomist', thus : 'I shall return after the British Association. The interesting question arises, Shall I have a row with the great O. there ? What a capital title that is they give him of the British Cuvier. He stands in exactly the same relation to the French as British brandy to cognac' (Life and Letters of T. H. Huxley y p. 161, vol. i.)

Another time he wrote about Owen to the German biologist Leuckart, thus: 'Particular branches of zoology have been cultivated in this country with great success, as you are well aware, but ten years ago I do not believe that there were half a dozen of my country- men who had the slightest comprehension of morphology, and of what you and I should call Wissenschaftliche Zoologie. Those who thought about the matter at all took Owen's osteological extravagances for the ne plus ultra of morphological speculation' (Life and Letters of T. H. Huxley, p. 163, vol. i.)

What wonder that with such feelings they vigorously contested the established views and pointed out the tremendous importance of the modern ones ! The older democrats were forced to look on helplessly while this new science grew up a science independent of the Universities and which, although democratic, was certainly not 'liberal' in its tendencies. When the older democrats called themselves 'liberal-minded' they meant to indicate that they were without convictions. The Church, the State, Science were to them purely im- personal things. Hence they were well suited to a univer- sity life in which the professors were supposed to play the part of anonymous officials, whose sole purpose it was to teach established views. It was the duty of these officials to cultivate the knowledge given into their care, to increase it, and to make it known to the public; but there must be no expression of any personal conviction regarding this knowledge the professor must be as un- prejudiced as the judge. The fear underlying this idea was that the equal rights of all mankind would be en- dangered by too much development of individuality. The Darwinists were threatening to upset this equilibrium, and nothing remained but to try to make them conform to the fundamental laws of Liberalism.

Let us try, first of all, to hear the vox populi. The 'Liberal' journals, as the Frankfurter Zeitung, the Augsbur- ger Allgemeine Zeitung, and the Berliner Nationalzeitung, were opposed to the theory, and gave the Darwinists ample cause for objecting to their behaviour. The veto of the Universities was also making itself heard. Du Bois Reymond gave his famous lecture On the Limits of Natural Knowledge in 1872. He was a professed materialist, but he showed in his lecture that the Darwinian philosophy cannot be followed to the bitter end, since psychological phenomena must be excluded from it. The materialists objected to the content of the lecture, and publicly pointed out its shortcomings. It had, however, a lasting influence.

On another occasion, in 1876, du Bois Raymond directly attacked the ideas of Haeckel. He remarked pointedly that his genealogical tree is to the exact scientist about as valuable as is Homer's genealogy of his heroes to the historical critic. Finally Virchow the old liberal played his part in destroying the last links that bound together the old and the new views of science. Virchow takes an important place as founder of a new school of thought in medicine. Before him medical practice was dominated by the so- called 'humoral pathology', which attributed all diseases to changes in the fluids of the body. Virchow replaced this view by one ascribing disease to cells which had under- gone pathological changes. For him, and for many after him, pathological anatomy became the basis upon which all medical work rests. This theory, still important, was then in its heyday, although the bacteriology of Pasteur and Koch was threatening its pre-eminence. The im- portance of this bacteriological theory of disease was later greatly increased by the growing knowledge of toxins and antitoxins, on which is based a view of disease that has some affinities with the ancient humoral pathology.

The reputation of Virchow was world-wide. He had, moreover, an accepted position as an anthropologist, and he was a member of the Prussian Reichstag. As politician and as scientist Virchow was a typical 'liberal 5 , a man not disinclined to adopt Voltaire's famous axiom, 'it is sufficient if only my tailor believes in God'. Let us examine, as an example of Virchow's method, his famous Gesammelte Abhandlungen zur wissenschaftlichen Medizin (1856). When it appeared it filled Haeckel with enthusiasm for its 'breadth of vision', its 'ideas at once philosophic and scientific', its 'critical and yet strongly monistic point of view' ; it also was the source which in- spired Biichner's materialism. The work deals with the usual problems of academic science, but the first chapters have stimulating titles On the Nature of Man, On Philo- sophy, On Science, On Life, and so on, and they treat these

problems in an original way. The book may be summarized thus: 'It presents the harshest materialism imaginable. For Virchow, however, this is hidden behind the confused tangle of ideas he connects with such words as Matter, Force, Causation, Inertia. These words are connected, even in the realm of Natural Science, with quite definite ideas, and they cannot be separated from those ideas without bringing absolute confusion into the whole of scientific phraseology' (Schleiden, t)btr den MaUrialismus der neueren Naturwissenschaft, Leipzig, 1863, p. 49).

Thus Schleiden described Virchow's style. The reader to-day will hardly agree with these strictures, but will ask why Virchow philosophized as he did, when, to judge by the tone of his writings, he believed philosophy to be so completely negligible. In the year 1877, at the annual meeting of the Society of German Scientists and Physicians at Munich, Virchow openly opposed Haeckel, who had spoken most enthusi- astically of Darwinism. Reminding his hearers of the fundamental views of 'his honoured master' Virchow, Haeckel claimed it as an irrefutable physiological fact that our inspiration depends upon the form of our nervous system. Since the nervous system is built up of cells, it is the cell (he held) that is the foundation of our psychic life. Our scientific ideas, therefore, point incontrovertibly to a 'cell-souP. Still following the ideas of Virchow, he con- tinued, and remembering that cells are built up from atoms and molecules, we deduce that these, too, must possess souls. The attractions and repulsions of atoms represent their loves and their hates. Their movement is their sensation, and it is at this point that the work of the psychologist begins. But if this is the incontrovertible truth, it is not enough merely to affirm it. We must also follow it to its logical consequences; we must introduce the theory into our schools as the fundamental principle upon which all our teaching is to be reorganized. The teaching of morality and of religion must also be reformed. The evolutionary theorist will base his ethical teaching on

that natural law which, in the form of blind instinct, dominates the animal world, and which is older than any system of morals. Away with Revelation! We will replace this by the recognition of the laws of evolution. This bold speech supplied the keynote for Virchow's lecture. He spoke first of the struggle for freedom in the expression of scientific opinion. 'The mere holding of this assembly and the speeches made at it sufficiently proves that science has won complete freedom. We must retain this privilege. Moderation, and the relinquishing of per- sonal predilections, will be necessary if public opinion is to continue favourable. 5 In a stimulating speech he then proceeded to point out the boundary which divides science from mere speculation. With biting irony he criticized Haeckel's views of soulful cells and of men descended from monkeys. So long as such ideas were unproven we should refrain from teaching them in our schools, where only established scientific views should be imparted. Prob- lems were subjects for research, not for instruction. Only when the theory of evolution became certainly established dare we base upon it our whole view of the world, of society, and of the state. And we must do this then, in spite of one very questionable feature of the whole theory its socialistic tendency.

We must remember that the lecture was given in 1877, when the socialists were held by all other parties, even by the liberals, as a danger to the State, and were being kept down by the most drastic methods. To the impartial observer of to-day two questions occur: Why did Virchow interfere in this debate on Darwinism ? And Was the Darwinian theory really so near to socialism ? By this time it was generally recognized that in Germany Darwinism represented, if not a new religion, at least a new faith. The partisans of the Church and of the new scientific theories were discussing ideas which were, to them, of fundamental importance. Virchow favoured neither Haeckel nor the Church; he was a

thorough 'liberal', 1 and as such had no sympathy with any conviction. As a scientist, seeking the truth, he had the right to ask Haeckel for proofs. But the public does not recognize the existence of any such right. Probably no one was ready to believe that Virchow had been moved to deliver this lecture simply by a love of truth. Both con- flicting parties Darwinists and clericals considered that he had recanted his earlier views. The Church papers praised him on this account, while the Darwinists looked upon him as antagonistic to the evolutionary theory.

Regarding the second question, the evolutionists Haeckel, Huxley, Darwin, Schmidt and others declared that the ideas of the social democrats could not logically be deduced from their theory. Virchow was certainly not of this opinion. For him Darwinism spelt dogma, fanaticism, and he saw the same fearful force in socialism. The might of this conviction could only lead to one thing in his eyes to Revolution. He saw, further, that the socialists really had definite leanings towards the doctrine of Natural Selection. The connexion between the two was very like the connexion between Darwinism and liberalism. Vir- chow looked at the whole question from the 'liberal' point of view. We see this in his naive assertion that men must only ^ teach the evolutionary doctrine when they were certain of it. As if the Darwinians as if Haeckel had any doubt concerning it ! They would have sworn by all they held sacred that it was true ; just as their clerical opponents tried by solemn oaths to strengthen the opposite view.

Haeckel answered Virchow's speech in his book Free Science and Free Religion (1878), perhaps the best piece of polemical literature produced by the whole contro- versy. Haeckel knows that the theory of evolution is true, and 'It never will be proved if those proofs which we already possess do not suffice'. He must therefore teach it, for 'He who knows the truth and does not declare it is indeed despicable'. There is no such thing, Haeckel holds, 1 Translator's note. The word 'liberal* is used all through this translation in its German sense.

as 'objective science', for there is no sharp boundary dividing fact and theory. All teaching must inevitably be coloured by the personal convictions of the teacher. Virchow's own teaching was itself entirely dominated by his own point of view, as Haeckel himself had found when he was his pupil. By his lecture Virchow had simply thrown his influence on to the side of the Church. Haeckel also dealt quite frankly with the relation between science and politics. Every new philosophy has its practical aims and so every new philosophy must inevitably influence political thought. Darwinism is, how- ever, an aristocratic rather than a democratic creed, since the whole theory rests on the belief in the inequality of man. Further, we must not forget how little our practice conforms with our theory. Do we not see this every day in the cleft between Christian teaching and the practice of Christendom ?

But despite Haeckel's eloquence the tide had begun to flow against Darwinism, and Haeckel's apology did not hold it up. Virchow had achieved his end. A few months after his speech there were two attempts to assassinate the Kaiser. One was made by a workman, the other by a Doctor of Philosophy. The socialists were blamed for these crimes, and they were used as political capital. Clerical newspapers did not hesitate to blame Darwinism. The Government asked the Reichstag for special power to suppress the Social-democratic party, and obtained it. The request made a dissolution necessary, but they obtained the right from the new Reichstag. These measures were undoubtedly a blow to the Darwinists.