an anatomical or physiological trait is to the influence of environment, the less definitely can we speak of a controlling influence of heredity, and the less are we justified in claiming that nature, not nurture, is the deciding element. It would seem, therefore, that the first duty of the eugenist should be to determine empirically and without bias what features are hereditary and what not.
Unfortunately this has not been the method pursued; but the battlecry of the eugenists, “Nature not nurture,” has been raised to the rank of a dogma, and the environmental conditions that make and unmake man, physically and mentally, have been relegated to the background.
It is easy to see that in many cases environmental causes may convey the erroneous impression of hereditary phenomena. We know that poor people develop slowly and remain short of stature as compared to wealthy people. We may find, therefore, in a poor area, apparently a low hereditary stature, that, however, would change if the economic life of the people were changed. We may find proportions of the body determined by occupations, and apparently transmitted from father to son, provided both father and son follow the same occupation. It in obvious that the more far-reaching the environmental influences are that act upon successive generations, the more readily will a false impression of heredity be given.
Here we reach a parting of the ways of the biological eugenist and the student of human society. Most modern biologists are so entirely dominated by the notion that function depends upon form, that they seek for an anatomical basis for all differences of function. To give an instance: they are inclined to assume that higher civilization is due to a higher type; that better health depends upon a better hereditary stock; and so on. The anthropologist, on the other hand, is convinced that many different anatomical forms can be adapted to the same social functions; and he ascribes, therefore, greater weight to the functions, and believes that in many cases differences of form may be adaptations to different functions. He believes that different types of man may reach the same civilization, that better health may be produced by better bringing up of any of the existing types of man. The anatomical differences to which the biologist reduces social phenomena are hereditary; the environmental causes which the anthropologist sees reflected in human form are individually acquired, and not transmitted by heredity. It would lead us too far to prove the correctness of the anthropologist’s view. It must suffice to point out a very few examples. Sameness of language acquired under the same linguistic environment by members of the most diverse human types, sameness of food selected from among the products of nature by people belonging to the same cultural area, similarity of movements required in industrial pursuits, the habits of sedentary or nomadic life, all of which are distributed
