468 KINSHIP AND ADAPTATION 



becomes simplified in the course of its evolution and, so passes 

 to a lower level of structure, it is said to degenerate. Much 

 more extreme instances of degeneration will be dealt with in 

 the following chapter. 



It thus appears that degeneration, persistence, and extinc- 

 tion of types accompanies the general progress which charac- 

 terizes organic evolution. In the evolution of human society 

 likewise we find degeneration, persistence, and extinction of 

 races along with a general progress of mankind from savagery 

 to civilization. Here as in the evolution of lower organisms we 

 may observe adaptation to changed conditions through sud- 

 den or gradual modification. Migrations also play an import- 

 ant part and have many consequences, among which conflicts 

 are the most apparent although not necessarily the most sig- 

 nificant. Periods of greater progress have been times of 

 greater peace. Conflicts destroy or test; they do not create. 

 Men or races unfit to live, if such there be, of course are better 

 dead, and those menacing the progress of mankind are better 

 subdued; but it is surely a partial view of human affairs that 

 regards the world as one vast battlefield whose horrors have 

 fostered the most precious characteristics of civilization. How- 

 ever inevitalile mortal conflicts have been, however fierce the 

 struggle of competition, and however necessarj^ it may have 

 been to kill the worse that the better might live, we cannot 

 say that anyone has been made better by the killing. Yet 

 we may be sure that human advance toward the most perfect 

 and abundant life 'has been delayed, and that whatever real 

 progress Man has made has been in spite of his competitive 

 struggles. The economies of co-operation and the advantages 

 of mutual service achieve what competition never can. j\Iere 

 struggle for supremacy when fiercest destroys most of what 

 is best. Man's mastery over nature and over his lower self 

 has come through learning and choosing the better way. 



The evolution of mankind and that of lower organisms 

 are alike in so many ways, it is thought that each may throw 

 light upon the other. In human progress we recognize as the 

 controlling factors of change: Opportunity, — ottered by the 

 environment; Experience, — representing its effect; Choice, — 

 as the response to it, guided by Id(\Us. Of these the pivotal 



