630 Causes and Course of Organic Evolution 



As compared therefore with proenvlronment in plants or 

 the simplest animals, man and the higher animals show one 

 marked feature of advance. For while in the former any 

 one organ takes a proenvironal course, that is a resultant of 

 several compounded stimuli acting by aid of cognitic energy, 

 in the latter many of the proenvironal courses taken are the 

 compounded resultant of several separate resultants, each 

 formed from compounded stimuli, as set forth in the last chap- 

 ter. It is this capacity for forming a complex compounded 

 resultant, which gives to higher animals, specially to ants, 

 apes, and very notably man, the rapid power of mapping out 

 proenvironal pathways, and of moving or acting along these. 



Emerson recognized, and crystallized in words, the law of 

 proenvlronment in its applicability to man, when he said: 

 "The genius which preserves and guides the human race indi- 

 cates itself by a small excess of good, a small balance in brute 

 facts always favorable to the side of reason." 



In illustration, examples of proenvironal action will be cited 

 first from personal or individual human life, and second from 

 social life. But various of the evolving life-conditions set 

 forth on pages of Chapter XX fit in perfectly under one or 

 the other head. In many national museums also, suites of 

 specimens are often exposed that form an admirable practical 

 illustration of proenvironal progress, as accomplished by man 

 in inventive achievement. 



The ordinary pocket-knife of two or three blades is a highly 

 useful article. We may recognize its first beginning in the 

 rude, somewhat flat, roughly chipped flint with ragged edge, 

 that man of the earlier stone age fashioned. Involved in 

 the fashioning of it were numerous and repeated heliotropic, 

 mechanotropic, apogeotropic, and other stimuli that were 

 passed mainly from the eye and the hand to the brain, there 

 to be summated into a resultant stimulus. But, as he com- 

 pared a very rough-edged with a smoother and more sharply 

 edged exami)le of his effort, he again summated both pictures 

 into one which caused him to evolve or fashion a tool that by 

 continued and careful polishing would give a quite uniform 



