SCIENCE AND REVOLUTION 



new race proves to be especially well fitted for 

 survival and in the course of the Tertiary period, 

 spreads over vast areas of the earth's surface and 

 conquers its animal life. 



Great geological catastrophes follow. The 

 Ice-Age overtakes the organic life of half the 

 earth. Man, having learned the use of fire, 

 drives the ferocious beasts out of their caves 

 and survives even here. Great floods surprise 

 many of the human beings when the ice melts. 

 Yet the race survives and spreads, growing in 

 brain volume and skill of fingers. They have 

 learned to think connectedly and to speak articu- 

 late languages. Their environment determines 

 the character of their social organization. 



In one respect, all the early social groups of 

 mankind are alike : They are all rooted in sexual 

 kinships, and descent is traced by the female 

 line. The rules of mutual intercourse growing 

 out of these relations are democratic and dic- 

 tated by direct observation of the evil effects of 

 violating natural laws of adaptation and sexual 

 selection. Nature itself teaches primitive man 

 to observe the laws of evolution. All ideas of 

 modern altruism, morality, love, liberty, brother- 

 hood, and the like, are etherealized and dete- 



184 



