574 HUMAN BIOLOGY 



germ cells, they are passed on through many forms of social 

 communication, through imitation, signs, language, writing, 

 education, customs and institutions. This has been called 

 "social inheritance," but it is not inheritance at all in the 

 biological sense but rather a part of the social environment. 

 By means of social continuity each generation is bound to 

 every other one, each later generation builds on the work of 

 earher ones. Thus science, art, government and culture in 

 general advance from age to age: whereas in germinal 

 inheritance later generations begin almost where earlier ones 

 began and not where they ended. It is this immensely 

 important difference between germinal and social inheritance 

 that makes biological progress so slow as compared with 

 social progress. It is this which causes knowledge to outrun 

 performance, and ideals to point the way to realizations. 

 It is this continuity and development of society from genera- 

 tion to generation which makes possible such a topic as 

 "the purposive improvement of the human race." And it is 

 this contrast between the rapid improvement of environment 

 and the slow improvement of heredity that causes many 

 persons to seek some short cut to the desired haven of a more 

 perfect human inheritance. Unfortunately no such short cut 

 has ever yet been found and so far as we know at present 

 the only possible method of improving heredity is by the 

 method of selective breeding. 



APPLICATION OF BIOLOGICAL PRINCIPLES TO HUMAN 



BETTERMENT 



These are the fundamental principles that govern individ- 

 ual and racial development and any program for the improve- 

 ment of the human race must rest upon these principles. 

 In what practicable manner can these principles be utilized 

 and controlled for race betterment? 



The tremendous improvements that have been effected 

 in almost all breeds of domestic animals and cultivated 

 plants by the method of selective breeding have led certain 

 enthusiastic eugenicists to predict that corresponding 

 improvements in the human race could be made in a rela- 

 tively short time by the same method, and many persons 

 have looked forward to a eugenic paradise in which all 



