426 HEREDITY AND ENVIRONMENT 



eliminated, we must face the conclusion that 

 practically all that can be accomplished will be 

 to preserve the race at its present level. It is 

 impossible, then, to apply rigidly to man the 

 methods of animal and plant breeders. So- 

 ciety cannot be expected to eliminate from re- 

 production all but the very best lines. The 

 great majority of mankind cannot be expected 

 voluntarily to efface itself. The most that can 

 be hoped for in this direction is that the great 

 mediocre majority may eliminate from repro- 

 duction a very small minority of the worst 

 individuals. 



Furthermore, other and perhaps even more 

 serious objections to the views of extreme eu- 

 genicists are to be found in human ideals of 

 morality. Even for the laudable purpose of 

 producing a race of supermen, mankind will 

 probably never consent to be reduced to the 

 morality of the breeding-pen with a total disre- 

 gard of marriage and monogamy. The geneti- 

 cist who has dealt only with chickens or rabbits 

 or cattle is apt to overlook the vast difference 

 between controlling reproduction in lower ani- 

 mals and in the case of man where restraints 

 must be self-imposed. 



