quainted with the history of philosophy, but his utterances usually make the impression on one that he has never done any serious work in this line, that his knowledge is largely based on hearsay, as it were. He certainly seems to be ignorant of modern psychology, otherwise he could not speak of it deprecatingly as he does. His criticisms may perhaps fit the psychology of fifty or a hundred years ago; they surely are not apt to-day. Here Haeckel appears to be fighting windmills of his own making. It is also plain that he is unfamiliar with modern epistemology and that a closer acquaintance with this subject would have saved him from falling into error and contradiction. Haeckel is fond of accusing men like Wundt, Helmholtz, Virchow, Du Bois-Eeymond and others of his age, who started out as materialists and afterwards abandoned the conceptions of their younger days, of cowardice or senility or both. It is barely possible, however, that a deeper insight into the mysteries of nature and a finer appreciation of the inadequacy of the materialistic hypothesis convinced these men of the error of their ways. Haeckel prides himself on having retained the courage of Ms youthful convictions. I think myself that he deserves credit for saying what he really believes, but the fact that he believes what he believes is no sign to me that his friends are in their second childhood, but that Haeckel is still in his first, so far as philosophy is concerned.