COSMIC PHILOSOPHY 



power of responding heterogeneously to exter- 

 nal changes, is the chief, though not the sole, 

 factor concerned in producing length of life. 

 The amount of normal longevity in any spe- 

 cies depends upon the definite heterogeneity of 

 the adaptation of its individual members to en- 

 vironing circumstances, and also upon the ratio 

 of their nutrition to their expenditure. But the 

 preponderant importance of the former factor is 

 seen in the fact that, in spite of their immensely 

 greater personal expenditure, the higher animals 

 are, as a rule, very much longer lived than the 

 lower ones. In the civilized human races also, 

 as contrasted with the savage races, the life is 

 not only higher in degree but longer in dura- 

 tion : the longevity of the lowest savages rarely 

 exceeds forty-five years. 



As we proceed to survey, in a single view, the 

 various truths here separately elucidated, we find 

 that the essential distinction, above insisted on, 

 between the sciences of biology and psychology, 

 is thoroughly justified by the very facts which 

 illustrate the close connection between the two. 

 The foregoing exposition conclusively proves 

 that in dealing with the adjustments of inner to 

 outer actions, biology " limits itself to the few 

 in which the outer actions are those of agents 

 in actual contact with the organism — food, aer- 

 ated medium, and things which produce certain 

 effects by touch (as insects which fertilize flow- 

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