RELATIONS OF EXPERIMENTAL PSYCHOLOGY 661 



a subjectivistic point of view the metaphysical problem is not faced, 

 but assumed to be non-existent, and with the elimination of phil- 

 osophy vanishes also the validity of science through the denial of 

 the fundamental assumption upon which the whole force of its 

 appeal depends. 



Within the field of descriptive psychology as thus defined we 

 are apparently met by a division into two sub-provinces of 

 theoretical and experimental science. The discrimination, however, 

 is a false one, if two separable processes are conceived, or two 

 independent systems of truth, however closely related. There is 

 but one science of psychology, as there is but one physics and one 

 biology. Every hypothesis in science must be susceptible of ex- 

 perimental verification, and the result of every test must either 

 confirm or correct an hypothesis. Theoretical science is but the 

 continuously elaborated structure which is rising on the basis of 

 experimental method, at once the inspiration and the product 

 of inductive research. In the concrete process by which know- 

 ledge advances these are aspects of an activity which in its essence 

 is single. It is only for didactic purposes that a logical analysis 

 is made, whereby the results are presented in isolation from the 

 complicated and difficult procedure through which they have been 

 reached. All descriptive science is popularized science, a rsum6 

 of conclusions presented in abstraction from their premises, and 

 in such a simplified form as may be grasped by minds which from 

 lack of information or discipline are unfitted to make independent 

 deduction of them. It is an indication of the undeveloped status 

 of our science that alongside of its legitimate subdivision accord- 

 ing to subject-matter there is also a division according to method, 

 into general (or theoretical) and experimental psychology. The 

 same general principles govern all research; the same criteria are 

 employed in the validation of scientific results, irrespective of 

 qualitative differences in their subject-matter; and the experi- 

 mental method is the uniform approach of every science to its 

 problems. 



Experimental psychology has no special or independent class 

 of phenomena to investigate by which it may be differentiated 

 from psychology at large. It has therefore no place as psych- 

 ology itself has in a classification of the sciences which pro- 

 ceeds upon the logical subdivision of the orders of reality and the 

 connections which obtain among them. The relation of experi- 

 mental psychology to the general science of mind is that of a method 

 of investigation to the body of doctrine which results from the 

 solution of the problems to which it offers a mode of approach. 

 Wherever discriminable ranges of phenomena are treated, the 

 investigation of each may be conceived independently. Thus the 



