454 HEREDITY AND ENVIRONMENT 



increasing the families of the better types as 

 well as of decreasing those of the worse. 



What Bernard Shaw regards as the greatest 

 discovery of the nineteenth century, viz., the 

 means of artificially limiting the size of fami- 

 lies, may prove to be the greatest menace to the 

 human race. If it were applied only to those 

 who should not have children or to those who 

 should for various reasons have only a few chil- 

 dren it would be a blessing to mankind. But 

 applied to those who could and should have 

 many children it is no gift of the gods. No 

 one denies that the chief motive for limiting the 

 size of families is personal comfort and pleas- 

 ure rather than the welfare of the race. The 

 argument that people should have no more chil- 

 dren than they can rear in comfort or luxury 

 assumes that environment is more important 

 than heredity, which is contrary to all the bio- 

 logical evidence. In the breeding of horses or 

 cattle or men heredity is more potent than 

 environment; and it is more important for the 

 welfare of the race that children with good in- 

 heritance should be brought into the world 

 than that parents should live easy lives and 



