THE PURPOSIVE IMPROVEMENT OF THE HUMAN RACE 569 



been paid to euthenics than to eugenics. Indeed almost all 

 the agencies that have been employed for the betterment of 

 mankind have been aimed at the improvement of the 

 environment. Among these are government, education, 

 rehgion, art, Hterature, science, medicine, sanitation, 

 engineering*; and practically everything which we include 

 in that social complex which we call civihzation. 



Only eugenics, which is the attempt, or rather the proposal, 

 by man to breed from the fit rather than the unfit, and 

 natural selection, which is this same objective attained by the 

 slow and wasteful processes of overproduction and the 

 ehmination of the unfit in the struggle for existence, are 

 directed to the improvement of heredity. And yet for 

 continuous and lasting human progress there must be 

 improvement of heredity as well as of environment. As the 

 motto of good photography is "Get it in the negative," 

 so the motto of good breeding is "Get it in the blood. " 



The only known method of improving heredity pur- 

 posively is by selective breeding, that is by mating individuals 

 that come of good stock and that show good quafities, and by 

 the prevention of the breeding of poor stock and of defective 

 individuals. No method is known by which inheritance 

 factors can be improved directly. Very rarely such factors 

 may undergo change, or what is called mutation, but such 

 changes are generally for the worse rather than for the 

 better and their causes are almost wholly unknown. Neither 

 the experience of breeders nor the principles of genetics 

 holds forth any hope that bad inheritance factors can 

 ever be purposively changed into good ones. The only 

 practicable method of improving heredity is by selection 

 of the best and ehmination of the worst. 



And yet there can be no progress apart from favorable 

 environment, and human progress is pecuharly dependent 

 upon it. Man's environment is more extensive and more 

 varied than that of any other hving creature and its effects 

 on his development and activity are correspondingly greater. 

 In addition to the same sort of environment which he 

 shares with other organisms, he is pecuharly affected by intel- 

 lectual and social stimuh. By means of language, institutions 

 and education, the experiences of men in all countries and 



