28o Darwin's Theory of Social Progress 



Darwin recognizes war as one of the factors in 

 the disappearance of the less civilized races, just 

 as a geologist recognizes earthquakes as one of the 

 causes of the folding of the earth's crust, but he 

 assigns to it a subordinate role and reveals his 

 truly scientific spirit, by enumerating it only 

 among a dozen other slow and invisible causes: 



Extinction follows chiefly from the competition of 

 tribe with tribe and race with race. Various checks 

 are always in action, serving to keep down the nimi- 

 bers of each savage tribe — such as periodical famines, 

 nomadic habits, and the consequent deaths of infants, 

 prolonged suckling, wars, accidents, sickness, licentious- 

 ness, the stealing of women, infanticide, and especi- 

 ally lessened fertility. If any one of these checks 

 increases in power even slightly, the tribe thus affected 

 tends to decrease; and when of two adjoining tribes 

 one becomes less numerous than the other, the con- 

 test is soon settled by war, slaughter, cannibalism, 

 slavery, and absorption. Even when a weaker tribe 

 is not thus abruptly swept away, if it once begins to 

 decrease, it generally goes on decreasing until it be- 

 comes extinct.^ 



He describes also the slow and invisible causes 

 of the disappearance of the barbarian races before 

 the civilized races: 



' The Descent of Man, p. 198. 



The true cause of the extinction of races, according to Darwin, 

 is to be found in these slow and unrecognized factors. Collec- 

 , tive homicide plays but an incidental r61e, serving at most to 

 hasten an otherwise inevitable process. 



