ioo NATURAL SELECTION AND 



place of the competition of animal organisms. 

 Imitation and reflection impose a check ont he 

 mere physical struggle for existence ; but, ac- 

 cording to this evolutionist theory of morality, 

 they are themselves the product of natural 

 selection, and not of a distinct cause ; and in 

 the effects which they produce upon customs 

 and ideas, the principle of natural selection is 

 not left behind, but applied in a new sphere. 



The growth of morality implies, of course, an 

 advance in brain development, by the elimina- 

 tion within each group of the inferior members, 

 and, in the struggle between groups, of the in- 

 ferior groups. Further, we must notice the 

 immense acceleration of progress rendered 

 possible by language ; and Mr. Wallace does 

 not seem to deny that the most complex of 

 human languages differs only in degree from 

 the sounds and gestures by which animals 

 convey their feelings and emotions to one 

 another. Language renders possible the trans- 

 mission of experience irrespective of transmis- 

 sion by heredity. By means of language and 

 of social institutions we inherit the acquired 

 experience, not of our ancestors only, but of 

 other races in the same sense of " inheritance" 



