I. Haeckel and His Opponents

Virchow's fight against the evolution doctrine appears indeed somewhat of a riddle when one reflects that this investigator, at the beginning of his career, before the publication of Darwin's Origin of Species, defended the doctrine of the mechanical basis of all vital activity. In Würzburg, where Virchow taught from 1848 to 1856, Haeckel sat “reverentially at his feet and first heard with enthusiasm from him that clear and simple doctrine.” But Virchow fights against the doctrine of transformation created by Darwin, which furnishes an all-embracing principle of explanation of that doctrine. When, in the face of the facts of palaeontology, of comparative anatomy and physiology, he constantly emphasises that “definite proof” is lacking, one can only point out, on the other side, that knowledge of the facts alone does indeed not suffice for the recognition of the doctrine of evolution, but there is needed in addition—as Haeckel remarks—a “ philosophical understanding” as well. “The unshakable structure of true monistic science arises only through the most intimate interaction and mutual penetration of philosophy and experience” (Haeckel, Natürliche Schöpfungsgeschichte, 34, Vortrag). In any case, the campaign which Virchow has carried on for many years past against the doctrine of descent, with the applause of theological and other reactionaries, is more dangerous than all the mischief which a “descent-religion” can cause in unripe heads. A technical discussion on the point with Virchow is made difficult by the fact that, fundamentally, he remains standing on a bare negation, and in general does not bring forward any specific technical objections against the doctrine of evolution.