422 INTRODUCTION TO PHILOSOPHY OF SCIENCE 



ciple at least leaves room for a human freedom which may 

 perhaps be demonstrated on other grounds. At any rate 

 there is no longer any conflict between the assumptions of 

 physical science and the demands of the moral consciousness. 

 Even granting, therefore, that science is entitled to legislate 

 for human life, it cannot destroy human freedom, for some- 

 thing analogous to this is manifest even in the physical 

 world. Nature exhibits loopholes in uniformity; hence, if 

 man is a part of nature he may still be free. This is approx- 

 imately the state of affairs which has given rise to the recent 

 interest in the problem. The problem itself may now be sub- 

 jected to analysis before an examination is made of the 

 views of certain contemporary writers. 



GENERAL CHARACTER OF THE PROBLEM 



What, then, is the problem of human freedom considered 

 in the context of science? It may be formulated somewhat 

 as follows: The complete act of behavior may be analyzed 

 in two ways. On the one hand there is the physical analysis, 

 which breaks up the total act into the movement itself, 

 such as raising the hand, or speaking, the brain-state which 

 is presumably its cause, then the brain-state which is pre- 

 sumably the cause of this, and so on backward in time. The 

 brain is the central organ of control with regard to bodily 

 processes, and is responsible for the instigation of all activity 

 which is not purely reflexive. On the other hand there is 

 the psycho-physical explanation, which breaks up the total 

 act into a similar bodily movement, the brain-state which 

 is presumably its cause, and the volition or mind-state which 

 is the cause of this. This analysis also admits that the brain 

 is the central organ of control and is responsible for the 

 instigation of all activity, but it insists that the brain is 

 only the instrument of the volition. Here, in fact, is the 

 origin of the problem of freedom versus determinism. The 

 physical and the psycho-physical explanations are identical 

 with regard to the movement and the brain-state. But the 

 problem lies in the exact status of this brain-state. Is it the 



