Major Prophets of To-Day

by Edwin E. Slosson

that a small part of my numerous embryo pictures (perhaps six or eight per cent) are actually "falsified" (in the sense of Doctor Brass), all those in fact in which the material at hand for observation was so incomplete or unsatisfactory that one was forced to fill up the gaps by hypothesis and to reconstruct the missing members by comparative synthesis in order to produce a connected chain of evolution.

Haeckel emphatically denies any deception or misrepresentation, and calls attention to the fact that such diagrammatic and reconstructed drawings are common to all physiological works and are necessary to bring out the desired points. As to whether Haeckel has transgressed the permissible limits of such schematization of material I should not be competent to decide. Thirty-six German men of science signed a condemnation of Haeckel; forty-seven German men of science, "though they did not like the kind of schematizing which Haeckel practiced in some cases", signed a condemnation of Brass and the Keplerbund. The numbers have no significance, since majorities never decide anything except the balance of opinion, but the group that stood by Haeckel contained more embryologists and zoölogists than the other.

So I will dismiss the subject by quoting the opinion of a biologist and evolutionist who is thoroughly appreciative of Haeckel's contributions to science. Professor V. L. Kellogg, of Stanford University, in reviewing the "Evolution of Man" in Science, says:

"Biologists are likely to be of two minds concerning the advisability of putting Haeckel's 'Evolution of Man' into the hands of the lay reader as a guide and counselor on this most important of evolution subjects. Haeckel is such a proselytizer, such a scoffer and fighter of those who differ with him, that plain, 'unadorned statement of facts and description of things as they are cannot be looked for in his books. Or, if looked for, cannot be found. But this very eagerness to convince; this hoisting of a thesis, this fight for Haeckelian phylogeny and Haeckelian Monism, all make for interest and life in his writings."

This whole affair is a striking illustration of Huxley's observation that a controversy always shows an unfortunate tendency to slip from the question of what is right to the relatively unimportant question of who is right. Haeckel's critics have rarely attempted to controvert his scientific work and in fact would not in most cases be competent to discuss it. Even if he were guilty of all the mistakes alleged, it would not materially affect his scientific conclusions.

In noting Haeckel's faults, we are in danger of failing to appreciate the marvelous constructive genius of the man; the creative imagination which is characteristic of the great scientist even more than of the great poet. It was this gift that enabled him to discern in a handful of slime dredged up by the Challenger from the depths of the sea an orderly system of living beings wherein each microscopic skeleton of silica found its natural niche. It was this power which enabled him to assist so largely in the transformation of zoölogy from a purely observative and descriptive science, as it was when he began his labors, to a rational, experimental, and prophetic science, as it was when he closed them. As Cuvier from a few bits of bone could construct a whole animal, so Haeckel from scattered species ventured to construct, as early as 1865, a family tree, including all living forms from monera to man. Faulty it is from the standpoint of our present knowledge, but yet it must command our admiration because of the insight he showed in perceiving natural relationships and the skill with which he bridged the gaps in his living chain by hypothetical forms. Just as the great Russian chemist Mendeléef was able to describe in advance elements then unknown, but which were discovered later and found to fit into the vacant places he had assigned to them in his periodic law, so Haeckel's anticipations have been in many cases confirmed by later science. It was his good fortune to be able to hold in his hand the skullcap and femur of the "missing link" which had for years been the jest of the anti-evolutionists. The apeman, or Pithecanthropus, which he had in 1885 described and named, was in 1894 discovered by Dubois in Java. The mind of Haeckel has such high tension that it leaps over the gaps in a demonstration like a ten thousand volt current.

His account of how he was led to doubt the dogma of the immutability of species must be quoted because it is an excellent illustration of the wisdom of the laboratory adage: "Study the exceptions. They prove some other rule."

The problem of the constancy or transmutation of species arrested me with a lively interest, when, twenty years ago, as a boy of twelve years, I made a resolute but fruitless effort to determine and distinguish the "good and bad species" of blackberries, willows, roses, and thistles. I look back now with fond satisfaction on the concern and painful skepticism that stirred my youthful spirits as I wavered and hesitated (in the manner of most "good classifiers", as we called them) whether to admit only "good" specimens into my herbarium and reject the "bad", or to embrace the latter and form a complete chain of transitional forms between the "good species" that would make an end of all their "goodness." I got out of the difficulty at the time by a compromise that I can recommend to all classifiers. I made two collections. One, arranged on official lines, offered to the sympathetic observer all the species, in "typical" specimens, as radically distinct forms, each decked with its pretty label; the other was a private collection, only shown to one trusted friend, and contained only the rejected kinds that Goethe so happily called "the characterless or disorderly races, which we hardly dare ascribe to a species, as they lose themselves in infinite varieties", such as rubus, salix, verbascum, hieracium, rosa, cirsium, etc. In this a large number of specimens, arranged in a long series, illustrated the direct transition from one good species to another. They were the officially forbidden fruit of knowledge, in which I took a secret boyish delight in my leisure hours.—Bölsche's "Life of Haeckel", p. 38.

Ernst Heinrich Philipp August Haeckel, to give him for once his full baptismal name, was born in Potsdam, February 16, 1834. He has a double inheritance of talent, for both the Haeckels and the Sethes, his mother's family, have contributed prominent names to German history, and the two families have intermarried more than once. It is a curious fact that Gustav Freytag, in his series of "Pictures from the German Past", should have chosen for his representative men of the nineteenth century two of Haeckel's ancestors: his mother's father, Christopher Sethe, Privy Councilor and defender of Prussia against Napoleon, and his father, Karl Haeckel, State Councilor.

But Ernst did not follow the family tradition and take to the law. He showed an unmistakable bent for natural science, so, as a compromise profession, his father had him trained as a physician. He took the medical course, and in obedience to his father's wishes consented to practice the profession for a year to see if he could make a success of it. During the year only three patients came to him, owing perhaps to the fact that Haeckel in order to get time for his biological researches had fixed his consultation hours from five to six in the morning. His father then gave up trying to make a doctor out of him and allowed him to go to Messina in 1859 to study marine animals. Haeckel straightway became engaged to his cousin Anna Sethe, and as soon as he got his appointment at Jena married her. Their happiness was brief. Two years later she died, leaving Haeckel, then thirty, so stricken that he felt that he could not long survive the blow, so he plunged with feverish haste into the preparation of his "General Morphology" in order to leave to the world his science and philosophy in a systematic form. It was written and printed, two thick volumes of more than twelve hundred pages, in less than a year, during which Haeckel lived like a hermit, working all day long and half the night, getting barely three or four hours sleep out of the twenty-four.