a E. L. THORNDIKE. 



of nice milk to drink, which does very well for a common- 

 sense answer. It also suffices as a rebuke to those who would 

 have the kitten ratiocinate about the matter, but it fails to tell 

 what real mental content is present. Does the kitten feel 

 *' sound of call, memory-image of milk in a saucer in the kitchen, 

 thought of running into the house, a feeling, finally, of' I will 

 run in 'f " Does he perhaps feel only the sound of the bell 

 and an impulse to run in, similar in quality to the impulses 

 which make a tennis player run to and fro when playing ? The 

 word association may cover a multitude of essentially different 

 processes, and when a writer attributes anything that an animal 

 may do to association his statement has only the negative value 

 of eliminating reasoning on the one hand and instinct on the 

 other. His position is like that of a zoologist who should to- 

 day class an animal among the ' worms.' To give to the word 

 a positive value and several definite possibilities of meaning is 

 one aim of this investigation. 



The importance to comparative psychology in general of a 

 more scientific account of the association-process in animals 

 is evident. Apart from the desirability of knowing all the facts 

 we can, of whatever sort, there is the especial consideration that 

 these associations and consequent habits have an immediate im- 

 port for biological science. In the higher animals the bodily 

 life and preservative acts are largely directed by these associa- 

 tions. They, and not instinct, make the animal use the best 

 feeding grounds, sleep in the same lair, avoid new dangers and 

 profit by new changes in nature. Their higher development in 

 mammals is a chief factor in the supremacy of that group. 

 This, however, is a minor consideration. The main purpose of 

 the study of the animal mind is to learn the development of 

 mental life down through the phylum, to trace in particular the 

 origin of human faculty. In relation to this chief purpose of 

 comparative psychology the associative processes assume a role 

 predominant over that of sense-powers or instinct, for in a study 

 of the associative processes lies the solution of the problem. 

 Sense-powers and instincts have changed by addition and 

 supersedence, but the cognitive side of consciousness has 

 changed not only in quantity but also in quality. Somehow 



