202 president's address — section j. 



importance on this account, and it has received a povverful stimulus 

 from its connection with the theory of evolution. If, it is argued, 

 there is reason to believe that all animals are descended from the 

 same primitive forms, is it not reasonable to believe that the intel- 

 ligence associated with these organisms has similarly developed? 

 On this hypothesis the problem of evolutional psychology is to 

 show how, in accordance with the known or inferred facts of 

 animal intelligence, the supposed development may have taken 

 place. The theory which presents itself for verification offers, at 

 the same time, a powerful stimulus to the investigation of facts. 

 Much has been done in collecting, verifying, and arranging facts 

 in a graduated series, and progress has been made also in 

 obtaining a criterion by which the first beginnings of animal 

 intelligence may be tested, and in fixing the intellectual limits 

 which sever the lower animals from man. Wherever we find the 

 power of making new adjustments or modifying old ones as a 

 result of individual experience, there we may infer with very great 

 probability the ])resence of intelligence. Ascending in the scale, 

 we must admit that our humbler brethren are capable of percep- 

 tion, memory, and imagination. They exhibit curiosity also, paying 

 attention to characteristics which interest them; and we cannot 

 deny them the power of reasoning, since they form expectations 

 on the strength of past experience. At the same time it would 

 appear that their reasoning is always about concrete facts. There 

 is no evidence that they can, like man, form abstract ideas in 

 which attributes are regarded in isolation from concrete things, 

 or that they can reason abstractly, or are capable of reflective 

 self -consciousness. I need scarcely add that in this region many 

 questions remain unsolved, and there is much which is open to 

 dispute. 



While, as I have said, it is the tendency of modern Science to 

 investigate these departments of psychology in abstraction from 

 the ultimate problems of philosophy, it is not to be understood that 

 the task of isolation is an easy one. I have not yet met with any 

 work on psychology which did not betray, more or less distinctly, 

 the philosophical tenets of its author. Philosophy is more closely 

 related to psychology than to the sciences which are occupied with 

 the material world. The physicist has no diflficulty in considering 

 the world of matter and motion in abstraction from the mind which 

 knows it. If he seeks to examine thoroughly the conceptions which 

 he is constantly using, and begins to inquire into the nature of 

 causation, of matter, and of force, he has left the physical sphere, 

 and has entered the metaphysical. But, as a physicist, he is under 

 no temptation to make the transition. With the psychologist it is 

 otherwise. At almost every point he is in danger of crossing the 

 dividing line. He must take for granted, to begin with, the existence 

 of mind. It is easy to say that he should occupy himself with the 

 facts or phenomena of mind. But what are the facts ? If it be 



