THE NEW PHYSIOLOGY. 77 



know are so few, but because the facts we already 

 know are inconsistent with the mechanistic theory. 

 If it is defended, it can only be on the metaphysical 

 ground that in our present interpretation of the in- 

 organic world we have reached finality and certainty, 

 and that we are therefore bound to go on endeavour- 

 ing to interpret biological phenomena in the light of 

 this final certainty. This is thoroughly bad meta- 

 physics, and equally bad science. It is the idea of 

 causation itself that has failed, and failed because it does 

 not take us far enough. We have not at present the 

 data required in order to connect physical and chemical 

 with biological interpretations of our observations ; 

 but perhaps the time is not far off when biological in- 

 terpretations will be extended into what we at present 

 look upon as the inorganic world. Progress seems pos- 

 sible in this direction, but not in the direction of extend- 

 ing to life our present every-day causal conceptions of 

 the inorganic world. 



I now wish to add a few words as to the relation of 

 physiology to medicine ; for I am one of those with an 

 intense belief in the intimate connection between the 

 two subjects, and it seems to me that the mechanistic 

 physiology of the nineteenth century has failed to take 

 the rightful position of physiology in relation to 

 medicine. What is the practical object of medicine ? 

 It is to promote the maintenance and assist in the 

 re-establishment of health. But what is health ? 

 Surely it is what is normal for an organism. By 

 " normal " is meant, not what is the average, but what 

 is normal in the biological sense — the condition in 

 which the organism is maintaining in integrity all the 



