82 SOCIAL HEREDITY AND SOCIAL EVOLUTION 



complicated human moral nature has been built upon 

 them in a purely artificial way; by which we mean 

 that it has been built as the result of the accumula- 

 tion of a long series of acquired characters trans- 

 mitted by social heredity. To understand this it is 

 necessary as the next step in our discussion to notice 

 how from these two fundamental instincts the ethical 

 conceptions of modern man may have been derived. 

 The data upon which the conclusions are based come 

 from studies of primitive races as well as from the 

 growth of the child's mind. In tracing this history 

 we must divide the subject into two parts : 1. The de- 

 velopment of moral codes. 2. The development of 

 the moral sense. 



Evolution of Codes of Morals 



The Family. — For any advance toward an ethical 

 nature above that shown by the simple instincts men- 

 tioned we must look first to the conditions of the 

 human family. The moral sense always involves 

 duties; and for animals living in nature there are no 

 duties, unless we count the instinct for reproduction 

 as implying a duty. Among animals each individual 

 looks out for himself and, as a rule, neither gives aid 

 to others nor expects it from others. Each is 

 attracted to that which pleases self and is repelled 

 from that which hurts self. Pleasure and pain are 

 for them the only good and ill. We cannot regard 

 the instinct found among low animals to sacrifice 

 themselves to the race as constituting a duty, since 

 the sacrifices are unconscious. Among the higher an- 

 imals we find a few birds and mammals among which 

 the mother may, for a few brief weeks, consciously 

 yield her interests to those of her helpless young. 



