In view of this, what psychologist can for a moment doubt that the old problem which F. W. H. Myers called the most insistent that ever haunted the mind of man has contributed very much to stimulate interest in Weismann’s doctrine of the immortality of the germ plasm and for a wide lay public has given a zest and interest in phenomena that can hardly be observed at all save through a microscope and by an expert. If we had an analysis of Weismann’s own consciousness from his first conception of this idea to its full development we should doubtless find the same factor. True, we search his writings in vain for any intimation that he recognized any such influence, but I think there can be no doubt that had he been a psychologist interested in the sources of his own motivations and had he left us an autobiography as intimate as that of Spencer, Wundt, or even Darwin, we should have seen that he realized that he was only giving a new answer to the oldest of all culture problems. Of course, no psychoanalyst or geneticist would claim that Weismann was seeking an _elixir vitæ_ or a new fountain of youth for himself or for others, but it would be equally extreme, on the other hand, to deny that in the very use of the concept and term immortal, as he applied them to germ plasm and protozoa, he was propounding a new if partial surrogate answer to the problem of a larger life for man. Indeed, we might go further and suggest that in his extreme pronouncements against the inheritance of acquired qualities he gave way to the same basal disposition or diathesis that made theologians so exiguous in formulating conceptions of the inviolability of divine decrees. Another underlying psychic determinant is found in the intense popular interest in investigations like those of Voronoff, Steinach, and Carrel, of which the latter is perhaps least conscious while the former is almost as tinglingly so throughout as Haeckel was of these older concepts. That highly differentiated and complex somatic tissues removed from the body and given a more fit medium, and kept from all products of decomposition, etc., can keep on functioning and growing for years, better than they had done in the body in which they originated, neither has nor is ever likely to have any real practical utility for prolonging or intensifying human life. The fact may have a certain moral for cleanliness and even for nutrition but we can never wash out the tissues of the body or keep each of its cells in an optimum environment. Yet even here the mind finds a faint if, all things considered, somewhat pathetic element of hope that old age and death may sometime be deferred.