256 MENTAL EVOLUTION IX ANIMALS. 



CHAPTER XVII. 



Instinct (continued). 



Examination of the Theories of other Writers on the 

 Evolution of Instinct, with a General Summary of 

 the Theory here Set Forth. 



MilI;, from ignoring the broad facts of heredity in the 

 region of psychology, may be said to deserve no hearing on 

 the subject of instinct ; and the same, though in a lesser 

 degree, is to be remarked of Baiii. Herbert Spencer, and his 

 expositor Eiske, express with strong insistence the view that 

 natural selection has been of very subordinate importance as 

 an evolving source of instinct. Lewes virtually ignores 

 natural selection altogether, but nevertheless is not in agree- 

 ment wiLh Spencer, inasmuch as Spencer regards instinct as 

 " compound reflex action," and the precursor of intelligence, 

 while, as we have already seen, Lewes regards it as " lapsed 

 intelligence," and therefore necessarily the successor of in- 

 telligence. Thus, while Lewes maintains that all instincts 

 must originally have been intelligent, Spencer maintains 

 that no instinct need ever have been intelligent.* The 

 deliverance of Darwin upon this subject I shall render 

 bye-and-by. 



The position of Mr. Spencer is severely logical, and this 

 renders easy the definition of the points wherein I here dis- 

 agree with him. His argument is that instinctive actions 

 grow out of reflex, and in turn pass into intelligent actions, 

 so that in his terminology an instinctive action need never 

 have been intelligent, and an intelligent action need never 

 become instinctive. He is express in saying that although 

 " in its higher forms. Instinct is probably accompanied by a 



* I.e., no true instinctive action occurring in all individuals of a species ; 

 lie recognizes the principle of lapsing intelligence in individuals. 



