6 Animal Intelligence 



and without quantitative precision by one science or group 

 of scientists comes to be treated more objectively, definitely 

 and exactly by another, it is of course a gain, a symptom of 

 the general advance of science. That geology may become 

 a part of physics, or physiology a part of chemistry, is testi- 

 mony to the advance of geology and physiology. Light 

 is no less worthy of study by being found to be explainable 

 by laws discovered in the study of electricity. Meteorology 

 had to reach a relatively high development to provoke 

 the wit to say that "All the science in meteorology is 

 physics, the rest is wind." 



These objections to be significant should frankly assert 

 that between physical facts and mental facts, between 

 bodies and minds, between any and all of the animal's 

 movements and its states of consciousness, there is an im- 

 passable gap, a real discontinuity, found nowhere else in 

 science; and that by making psychology responsible for 

 territory on both sides of the gap, one makes psychology 

 include two totally disparate group of facts, things and 

 thoughts, requiring totally different methods of study. 

 This is, of course, the traditional view of the scope of 

 psychology, reiterated in the introductions to the standard 

 books and often accepted in theory as axiomatic. 



It has, however, already been noted that in practice 

 psychologists do study facts in disregard of this supposed 

 gap, that the same term refers to facts belonging some on 

 one side of it and some on the other, and that, in animal 

 psychology, it seems very unprofitable to try to keep on 

 one side or the other. Moreover, the practice to which the 

 study of animal and child psychology leads is, if I under- 

 stand their writings, justified as a matter of theory by 

 Dewey and Santayana. If then, as a matter of scientific 

 fact, human and animal behavior, with or without con- 



