66 SOCIAL HEREDITY AND SOCIAL EVOLUTION 



than once among primitive men, while it has never 

 appeared to any extent among animals, we are faced 

 with the significant question as to why man alone has 

 developed language. 



It is self-evident that language from the beginning 

 has been of the nature of acquired characters and 

 has been handed on by social heredity only. It has 

 been recreated by the mental activity of each genera- 

 tion of mankind. It has never found its way into the 

 germinal substance and no language is given to 

 the race by organic inheritance. One generation 

 has learned from the last, and then each genera- 

 tion has its opportunity to add to this inheritance by 

 contributing new words or new methods of using 

 words. The structure has thus been intelligently 

 built up step by step, and any generation, or, indeed, 

 any individual, may by its or his own efforts add to 

 the heritage which the next generation will receive — 

 a privilege which it does not have in regard to the 

 characters transmitted by organic heredity. Now, we 

 must remember that human civilization is absolutely 

 dependent upon the mental power, and that the pow- 

 ers of the human mind are wholly dependent upon 

 language. We cannot think of society without lan- 

 guage, for it could not exist. The foundation of 

 human evolution, then, is not based upon man's phys- 

 ical structure, but upon his developing a language, 

 and this is based not upon organized inheritance, but 

 upon social inheritance. 



The Development of Language and Mental 



Evolution 



It is not impertinent to our topic to note how 

 intimately language and mental evolution are con- 



