338 SOCIAL HEREDITY AND SOCIAL EVOLUTION 



principles of social evolution has reinstated the 

 force of the enviionnient in the development of social 

 though not in the development of organic evolution. 

 In a sober consideration of the principles of modern 

 eugenics it behooves us, therefore, not to reject or 

 overstate the effect of either of these two forces, but, 

 rather, to carefully determine their relative influ- 

 ence. With the eugenists we may recognize that all 

 features of our bodily structure are controlled by 

 the laws of inheritance. With them too we must 

 admit that one's innate mental powers are largely 

 or wholly matters of organic inlieritance ; and prob- 

 ably, though this is less certain, the same is true of 

 the moral sense with which each is endowed. So far, 

 then, as concerns the problem of improving our phys- 

 ical nature, or the innate mental ability and the keen- 

 ness of the moral instinct, this must be done, if done 

 at all, through the control of marriage. This is what 

 our eugenists are trying to emphasize and to bring 

 about. But we must not forget, in the enthusiasm 

 with which we welcome improvement in this direc- 

 tion, that there is another even larger side of the 

 question. Organic heredity simply gives us certain 

 powers, while social heredity determines what we 

 shall do with those powers. Man is molded into a 

 social individual by social forces, and whether or not 

 he fits into our society depends more upon the social 

 forces at work than upon the powers that nature 

 gave him. Even though he have an inheritance weak 

 both mentally and morally, an individual may be 

 molded into a fairly good member of the social or- 

 ganism if he is surrounded by proper environment; 

 but if he is reared in the wrong environment, tending 

 to produce a wrong social inheritance, he will be an 



