146 S. J. HOLMES 



pleasant experience it derives in some way inhibits further action 

 towards that class of objects. 



We have in this modification of instincts through the pleasur- 

 able or painful effects they produce the beginning of intelligence. 

 The pecking, swallowing, and avoidance of certain objects are 

 purely instinctive acts based on the chick's inherited organization. 

 After its first experiences with pleasant or nasty caterpillars the 

 chick is a different creature; it has learned by experience; and 

 henceforth its acts, which at first were in a general way adaptive, 

 become more perfectly adapted to its needs as the result of its 

 learning. Instinct supplied the impetus to action and in a meas- 

 ure determined the direction of action, but intelligence refines 

 upon the instinctive behavior and effects a closer adjustment 

 to the environment. 



In lower forms associations are formed as a rule with great 

 slowness. Behavior is almost entirely instinctive, and the organ- 

 ism can be made to deviate from its stereotyped methods of action 

 only with difficulty. It is probable that in low forms where 

 associations of only the simplest kind can be established there is 

 no association of ideas involved; and in fact there is no conclu- 

 sive evidence of the existence of ideas even in animals quite high 

 in the scale. Most animal learning consists in forming associa- 

 tions between certain sense experiences and certain actions which 

 bring pleasure or pain. A common way of teaching an animal 

 a trick is to try in various ways to induce it to perform the desired 

 action and then to reward it by food or some other means of giv- 

 ing it pleasure. In this way the connection between the situa- 

 tion and the act is reinforced and the act follows more readily 

 when the animal is placed a second time under the same conditions. 



Consider the case of a cat placed in a box which can be opened 

 by pressing down a lever or pulling a string, as in the experiments 

 of Thorndike. If the cat is hungry and food is placed outside, 

 the animal will probably make a vigorous effort to escape by 

 clawing and biting in various parts of the enclosure, which are 

 the usual instinctive methods employed in similar situations.. If 

 the right movement is hit upon and the cat gets out and secures 

 food, it will probably make its escape more readily than before 



