I.— PHYSIOLOGY. 165 



teleological manifestations are accidental. As that thoughtful writer 

 Hjort remarks, however : ' When we, as human beings, call a thing 

 accidental, it only means that we give up the hope of understanding 

 it. . . .' 'In the physical sciences those factors are termed accidental 

 which we voluntarily disregard in the course of an investigation, or which 

 we find we have omitted to notice.' Kant, however, in his Kritik of Judg- 

 ment calls the teleological ' the link whereby our understanding can alone 

 be supposed to find any agreement between the laws of nature and our 

 own power of judgment.' 



Mechanistic interpretations tend in the long run to become arrogant 

 and superficial, as vitalistic ones predispose to scientific nihilism. For, 

 while it is inconceivable that living things do not obey the laws of nature, 

 yet it is equally unthinkable that a chance encounter of physico-chemical 

 phenomena can be the explanation of their existence. This being so, how 

 can we, in Kant's words, ' arrive at an understanding of nature ' ? 



It seems clearly impossible to harmonise or to decide between these 

 opposed views of the nature of life, and I do not think any final conclusion 

 to be possible or even necessary. To quote Hjort once more, ' Philosophy 

 has no other starting point than a problem, and the current results of 

 scientific research ; it never leads to any absolute conclusion. It grows 

 with the science of nature, since in reality it comprises the most general 

 results of that science and comprises nothing more. It does not explain 

 the nature of the human understanding, and provides no means of getting 

 behind the understanding itself . . . the existence of which is the first 

 and necessary condition for the existence of science at all.' 



Physiologists, in attempting to know what life is, have in my opinion 

 attempted too much, and I think that a new standpoint is essential. One 

 of the greatest of contemporary thinkers, L. J. Henderson, has recently 

 submitted an argument with which I venture humbly to agree. The idea 

 of adaptation, urged by Claude Bernard, should be adopted by physiology 

 as its basal principle, as the chemist accepts the conservation of matter 

 or the physicist the conservation of energy. We need not seek to know 

 why it is so : that is the province of the philosopher ; all our experience 

 tells us that it is so. It is not a definition of what life is, but a brief state- 

 ment of its way, which is valuable, stimulating and true. But we must 

 treat the organism and its environment as one if we are to gain a proper 

 insight into the adaptations manifested by the former. Life is conserved 

 by adaptation, and I venture to think that this conception will be useful 

 alike to general biology, to physiology and perhaps most of all to pathology. 

 For there is no fact in biology, pathology or therapeutics which may not 

 profitably be viewed from this fundamental physiological standpoint. An 

 essentially similar standpoint has been reached by Haldane, who says : 

 ' We can reach no other conclusion than that it is the very conceptions of 

 matter and energy, of physical and chemical structure and its changes, 

 that are at fault, and that we are in the presence of phenomena where 

 these conceptions, so successfully applied in our interpretation of the 

 organic world, fail us.' It is the concern of physiology to study the 

 normal functions, and here the normal must be regarded as a statistical 

 group. For particular purposes it is convenient to consider normals as 

 of fixed value ; thus the normal man has a body temperature of 37.5°(.'., 



