to advance independently of heredity." Contrast man and other animals. The animal carries over from his parents and from his racial stock the physical equipment and the functional tendencies which enable him to fight the battle of life precisely as his ancestors fought it. If his type varies under natural conditions, it varies so slowly that, as a rule, many generations are required to disclose the change. With man all this is different. As I just now observed, nurture is cumulative. Each succeeding generation takes up its heritage, not where the preceding generation began, but where it left off. Each has to advance by first absorbing the new attainments of its immediate ancestors. In a real sense, therefore, because he has language and books and institutions and traditions, man is
the heir of all the ages.
Notice, however, that man comes into his social heritage only by acquisition during his individual life, by his own individual efforts. Is he, now, as a conscious being, better and better endowed as time goes on for the process of absorption? Does talent grow as knowledge grows? Does mental capacity keep pace with social accumulation? May we not suppose that the men and women of some distant glacial age, who dwelt upon the ice, wore the skin of the seal, and ate raw fish, had as much brain and as generous a measure of talent as have their remote descendents who wear sealskins, and eat ices and caviare? We can not say that they had not. On the contrary, our records, so far as they go, indicate that the social heritage has outstripped the hereditary growth of mind—that, as regards mental endowment, we begin very much as our distant forbears began; only, we proceed at once to burden ourselves with information and obligation which for them did not exist. To compass languages and sciences and histories and arts, and a complicated social and political regime, we are supplied with virtually the same minds that primitive man used for his primitive wants. Is it any wonder, then, that education is the central problem of an advanced civilization?
The question has been raised, however, whether it is not time to look beyond education to the possibility of improving the human stock; whether education is, after all, the only way of civilizing the individual. When the garden vegetable or the domestic animal fails to meet our needs, we improve its breed—so the argument runs; we breed for size, for strength, for flavor, for color, for endurance, for speed, or for general service. When we find that the part of our human stock which is best fitted to carry the cumulative load of civilization is weak, or degenerate, or inclined to sterility, why do we not look to the improvement of those strains that are mentally fittest and to the elimination of the bad? The argument, you observe, assumes that mental endowment and mental capacity are heritable possessions. Is the as-
