ANIMAL AND RATIONAL INTELLIGENCE 183 



after reflection and training. This constitutes our 

 difficulty in explaining instinctive action. Hence 

 it is that an exact definition of instinct is impossible. 

 That which is only partially known to us, and known 

 only in an external way, cannot be exactly denned. 

 On this account, general descriptions, such as that 

 just quoted, must suffice to indicate that we have 

 identified certain phenomena of organic life which 

 are not obviously capable of explanation by reference 

 either to sensibility or to intelligence. 



The puzzles of animal instinct are to be attacked 

 from the side of activity, leading to inference as to 

 potentiality. We must leave in abeyance, for the 

 present, the question as to the manner of execution. 

 Such reservation of the question is warranted by the 

 admission that instinctive actions are not the result 

 of experience. The single line of approach must 

 be recorded observations of animal conduct. These 

 are exceedingly varied, and are rich in suggestive- 

 ness. It is impossible to doubt that a truer con 

 ception of Nature is to be reached by more success 

 ful interpretation of animal instincts. At the same 

 time our prospects of success are greatly restricted by 

 the fixed conditions of the inquiry. Much more easily 

 and certainly can we advance towards exposition of the 

 action of intelligence itself than of instinct. In many 

 cases, the examples of instinctive action present a 

 most complex set of relations. Only the results are 

 known. How the actions are accomplished, is a 

 question which observational science cannot answer. 



Our main dependence must be on classification of 

 facts, such as may warrant inductions. Such classifica 

 tion may most readily be formed by reference to the 



