10 A MILLION YEARS OP CHILDHOOD 



plain reason why mental evolution has been so rapid 

 in the period of civilization. Man had first to develop 

 I intelligence enough to create an environment which 

 would foster intelligence. 



That is a fair explanation of the advance during 

 the historical period ; but we still fail to see why the 

 struggle with nature — the struggle for life — worked 

 so feebly in developing man's intelligence during the 

 earlier period. Few authorities on the subject seem 

 to have realized the need of explaining this, and I 

 have found no reason to modify the explanation which 

 I have advanced for the last ten years. It is that 

 man had no social life during the far greater part of 

 the prehistoric era, and his real progress began when 

 the conditions of an Ice Age compelled him to adopt 

 social habits. 



The question of the social factor in the evolution 

 of civilization has given rise to a good deal of confu- 

 sion. Prince Kropotkin and Dr. A. Russel Wallace 

 exaggerated the importance of the social factor (as 

 opposed to Darwinian struggle). The fact is that 

 social types of animals belong only to the last 

 geological period, and that even these — beavers, bees, 

 ants, wolves, wild cattle, etc. — have little intelligence, 

 which is not on the same line of development with 

 instinct at all. It is often forgotten that the evolu- 

 tionary value of social life depends mainly on the 

 power of communication between members of the 

 social group, and this is very slight indeed among 

 the lower animals, and seems to have been little 

 better in prehistoric man until the Ice Age. It is, 

 therefore, quite a mistake to think that it helps us to 

 suppose that man was from the first a social animal ; 

 as various sociologists have affirmed (on no evidence), 



