Page:Popular Science Monthly Volume 14.djvu/337

Rh of the transformation of species once inhabiting open space and endowed with visual power into blind creatures with a very restricted range; but for men who, like Virchow, do not know these relations, the experimental proof might be given. Who will deny that such experiments would further science?

In the third chapter, "Cranium Theory and Ape Theory," Haeckel considers a familiar question, treated already by Virchow in a lecture delivered in 1869, on "The Crania of Men and Apes." Unfortunately, in regard to this very question, Haeckel has, by his extravagant theses, seriously weakened the ground on which he stands, if he has not swept it clean away. Once you say "Man is a true catarrhine monkey," then it is difficult to meet the swarm of objections that will be raised. Virchow's discourse was one of the weakest ever published on this subject, and, although the author directed his polemic chiefly against me, I have not seen fit to make any reply, because I should have had only to point out and meet a misunderstanding (whether intentional or not I will not decide) of what myself and others have said. Virchow himself, in that essay, declared that "the resemblance of young monkeys to human children is very much greater than that of old monkeys to adult and fully developed men;" but he is unable to see that this, and the fact that as they advance in age the differences become more pronounced, necessarily lead us to suppose a point of time in the remote past at which the two types developed in divergent directions. Haeckel, then, is perfectly justified when he says in his reply, "From this inevitable grouping results the common origin of man and monkey from one ancestral form;" and I observe with pleasure that here, again, Haeckel abandons his extravagant theses, and lays down propositions which must be regarded as entirely tenable.

Even if to me, as to Oscar Schmidt, Haeckel's doctrines concerning the "memory of the plastidules" and the "psychic activity of the cells" appear only as a "shipwrecked hypothesis," and not, as their author believes, "the sure foundation of empirical psychology," nevertheless, I must, on the other hand, admit that Haeckel simply demolishes Virchow's position in his fourth chapter on "The Cell-Soul and Cellular Psychology." That in the development of the psychic faculties of the organism we have the same process of perfectionment, the same division of labor, the same gradual differentiation, as in the development of the bodily organs and tissues, cannot be doubted; but when, at Munich, Haeckel asserts that we have in the several individual cells the self-same manifestations of psychic life, of sensation, and of thought (Vorstellung), of will, and of movement, which are seen in higher animals made up of many cells, he exaggerates; this exaggeration can, however, in part be accounted for by the fact that language possesses no terms to denote the obscure and in some sense confluescent expressions of these lowly psychic activities. But Virchow has the assurance to say to the assembled naturalists and physicians: "There is no doubt that, for us,