Life and Instinct 195 



difficulties grow apace. From the operation of our own minds 

 we infer by analogy what takes place in the minds of animals, 

 a form of reasoning which is apt to lead us astray, but since it is 

 possible to study animal life only objectively and as it were at a 

 distance, such a course is in some degree inevitable. It is best, 

 therefore, not to press analogies farther than the observed facts 

 will warrant. A good rule is to discard second-hand informa- 

 tion, and to remember that isolated, disconnected, and therefore 

 imperfect observations are often a fruitful source of false ideas. 

 We must further guard against the popular tendency of reading 

 into the actions of animals the whole gamut of human feeling 

 and capacity, that fatal pitfall which claims so many incautious 

 writers. 



Life implies action and movement, and response is its most 

 striking characteristic. The study of the animal which re- 

 sponds, and of the theater of its response the world about it, 

 leads up to the most interesting if not most important study of 

 all the activities or behavior of the 'living, going machine,' 

 and to the successful interpretation of behavior every science 

 must be made to contribute. 



That the movements of living things, unlike those of arti- 

 ficial machines, are mainly adaptive, or that they tend to pro- 

 mote their welfare or that of their offspring, cannot be denied. 

 In some cases the responses of the higher animals are without 

 doubt useless or indifferent, but it is obvious that in all important 

 matters they cannot persist in a harmful course without serious 

 results. 



Every animal at birth inherits with its bodily organs the 

 power to use them in a more or less definite way, and all the 

 higher animals, as far down the scale as the insects at least, 

 learn to do things in the course of their lives, and thus display 

 a form of memory. Their equipment therefore embraces: (i) 

 unlearned or inherited powers, and (2) learned or acquired 

 abilities, which are the results of experience often very bitter. 

 The animal's powers, in other words, consist of free gifts at its 

 start in life, and of later acquisitions gained through its own 

 efforts in the struggle for existence. 



