18 THE NEW PHYSIOLOGY. 



scious adoption of a common-sense idea which is some- 

 what vaguely, perhaps, present in the minds of all men, 

 and which lias in reality guided biological advance in 

 the past. This idea, as I have tried to show, is a work- 

 ing hypothesis which actually works, and affords clear 

 guidance for future advance. 



I would fain add a few words as to the relation of 

 physiology to psychology and ethics : for this is a sub- 

 ject of deep human interest. We know that at any 

 rate the higher organisms are conscious and intelligent. 

 This fact brings physiology into touch with a new 

 element in the behaviour of organisms. The subject is 

 far too great a one for me to attempt to discuss here, 

 but I should like to say that it appears to me very clear 

 that just as biology is something more than physics 

 and chemistry, so psychology is something more than 

 physiology with the added assumption that conscious- 

 ness is tacked on to certain physiological processes, if 

 such a crude conception has any definite meaning. We 

 can, it is true, by a process of abstraction treat sensa- 

 tion from the purely physiological side, as in investi- 

 gating the physiology of the sense-organs ; but this is 

 physiology and nothing else ; for we are leaving out of 

 account the distinctive elements of consciousness. At 

 our present stage of knowledge life is not intelligence, 

 and men or animals as intelligent individuals involve a 

 deeper aspect of reality than biology deals with. Our 

 fundamental physiological working hypothesis cannot 

 be successfully applied to the phenomena of intelligence, 

 and the sooner and more definitely this is realised the 

 better for physiology. 



In conclusion, let me endeavour to state shortly the 



