326 Mutual Aid as a Law of Nature 



and that these checks result principally from an 

 insufficiency of subsistence . . . . ^ 



But what causes insuf^ciency of subsistence? Ac- 

 cording to Mai thus the ultimate limit of subsistence 

 is lack of space on the earth upon which food can 

 grow; but the earth has never yet been populated 

 to its limits and this cannot be the ultimate limit- 

 ing factor which has operated in the past or 

 which operates at the present time. Malthus 

 devotes a chapter to the study of the checks to 

 population among the American Indians and says : 



Under such circumstances, that America should be 

 very thinly peopled in proportion to its extent of 

 territory is merely an exemplification of the obvious 

 truth that population cannot increase without the 

 food to support it.^ 



But the same continent which supported with 

 difficulty a few thousand Indians, now supports 

 more than one hundred million people, still in- 

 creasing without any indications of pressing upon 

 the limits of subsistence. What is the essential 

 difference between the wandering tribes of Indians 

 who peopled this continent a few centuries ago, 

 and the present civilization, which produces not 

 only enough foodstuffs for its own use, but exports 



' Malthus, An Essay on Population, Everyman's Library, vol. 

 i., p. 304. 



' Idem., p. 26. 



