THE ERA OF HELPLESSNESS 55 



a complex and lengthy series of accidents, such as 

 could induce a stolid brute to go through the motions 

 and mental changes recited in the second paragraph 

 above, would be accidentally repeated in the same 

 order, etc., so frequently as to teach that brute the 

 habit of making those motions deliberately. 



It is very different, however, with an instinct or 

 predisposition; for these originate by variation, 

 are transmitted through heredity and increased by 

 selection. In sexually reproducing organisms vari- 

 ation produces an infinite variety of types and of 

 structural arrangements within their bodies. No 

 specimen among these organisms and structures is 

 in every particular exactly like any other. The vast 

 majority of them is either not, or at best but poorly, 

 adapted to their environing conditions. At rare 

 intervals specially and wonderfully adapted speci- 

 mens occur. This applies to races, individuals, 

 organs, tissues, and structural arrangements. It 

 applies to the nervous system, to nerve substance, 

 and to structural arrangements of nerves. 



Among the rarely occurring structural arrange- 

 ments of nerves some have happened capable of 

 initiating motions, which, under suitable conditions, 

 favor the reproduction and survival of the type of 

 organisms possessing these structures and perform- 

 ing these motions. Such nerve structures are the 

 causes of so-called instinctive actions, which, being 

 selected, are then transmitted as race instincts. 



The wonderful instinct of a certain wasp, which 



