I. Haeckel and His Opponents

It has been, however, this necessary conclusion which has summoned to battle all the old prejudices of theologians, philosophers, and all who are under their spell. Doubtless, people would have accepted the emergence of the single animal and plant forms from one another if only this assumption had not carried with it at once the recognition of the animal descent of man. “It remains,” as Haeckel emphasised in his Natural History of Creation, “an instructive fact that this recognition—after the appearance of the first Darwinian work—was in no sense general, that on the contrary numerous critics of the first Darwinian book (and among them very famous names) declared themselves in complete agreement with Darwinism, but entirely rejected its application to man.” With a certain appearance of justice, people relied in so doing on Darwin's book itself, in which no word is said of this application. Because he drew this conclusion unreservedly, Haeckel was reproached with being “more Darwinian than Darwin.” True, that held good only till the year 1871, in which appeared Darwin's work, The Descent of Man and Sexual Selection, in which Darwin himself maintained that inference with great boldness and clearness.