THE EVOLUTION OP THE MORAL SENSE 119 



been in advance of the average. What was the 

 cause of these advances which placed some ahead 

 of the race? 



This question is plainly akin to that of the origin 

 of variations in general, a question which still re- 

 mains one of the puzzles of biology. Living on the 

 same street we may find those whose conscience is 

 so highly developed that they will sacrifice life to 

 their ideal of honor, and others in whom the sense is 

 largely lacking. What makes the difference? Educa- 

 tion doubtless explains it to a degree but not wholly, 

 since two individuals with identical education may 

 develop different grades of conscience. The moral 

 sense is not even to-day wholly a matter of social, but 

 must be in part a matter of organic inheritance. 

 Still more true must this have been in regard to 

 whatever of this instinct primitive man possessed 

 before the formation of society, but the possession 

 of which enabled him to form society. Somewhere 

 back in human history there must have occurred 

 some new impulses among men which led toward 

 a willingness to sacrifice self-interest. It may have 

 started in such a small way as to be only a sugges- 

 tion, or it may have come suddenly like what the 

 biologist calls mutation. It was this phase of the 

 subject which Huxley had in mind when he stated 

 that it was necessary to attribute the ethical nature 

 to a "spontaneous variation," a statement made 

 before the modern ideas of mutations had dawned. 

 Mutations occur in other characters, and may surely 

 have occurred on these lines also. We must recog- 

 nize in human nature some internal law furnishing 

 successive variations along the direction of impulses 

 to sacrifice self-interests which have formed the 



