No. 49S] 



PHYSIOLOGY 



4<>1 



began to be defined as tile science of the physics and 

 chemistry of living tilings. Such is the prevailing con- 

 ception to-day. 



Is the vital process more than physics and chemistry! 

 Two facts stand out strongly in the physiology of the 

 present day. One is the constant extension of physico- 

 chemical principles into the explanations of hitherto mys- 

 terious functions; the other the seeming inadequacy of 

 those principles to explain other functions. In their atti- 

 tude toward this apparent inadequacy physiologists, while 

 disavowing with almost entire unanimity their belief in 

 the vital force of a century ago, may be said to be col- 

 lected at present into two camps. By far the majority, 

 while not denying the existence of puzzling problems, are 

 yet possessed of an optimistic spirit and look forward 

 with serenity to the unraveling of the mysteries of the 

 organism, as the mysteries of the inorganic become more 

 clear. They look at life, not as a distinct entity permea- 

 ting and vitalizing a complex machine, but rather as the 

 sum of the activities of that machine. In the opposite 

 camp there are a few souls who. though they too have 

 cast off the dross of the old conception, are rendered 

 impatient and despondent by the occasional failure of 

 present knowledge to explain, and they fly for refuge to 

 a refined and essentially inexplicable vital residuum. 

 They have succumbed to the inevitable reaction that 

 follows rapid progress. But they are not vitalists, they 

 say, at least not paleo-vitalists : they are neo-vitalists. 

 Into the intricacies of neo-vitalistic views and into the 

 shades of difference existing between them it is not oppor- 

 tune here to go, for they exert practically no influence on 

 the physiology of the time. The hopeful investigator 

 continues his endeavors, and with success, to interpret 

 vital processes in accordance with physico-chemical laws. 

 It seems to me that this is the most promising method. 

 For less than one hundred years has it avowedly been in 

 vogue, and these have been the years of most rapid ad- 

 vance. In this time many mysteries seemingly inex- 



