24 THE BIOLOGICAL PROBLEM 



of the inorganized world and that of organized matter. There 

 is much to be said, especially since the last few years, on the 

 value of this determinism, for it has lost the character of 

 absolute rigidity which was before attributed to it. 



This question will be discussed more fully a litde farther 

 on. At any rate, the phenomena which enter into the field 

 of our experimental studies are of an order of magnitude 

 such that it can be admitted that everything occurs as if this 

 determinism was absolute. In the same way, certain of our 

 concepts were modified by the theory of relativity, but the 

 description and quantitative examination of the objects of 

 our experiments have not been practically affected. We again 

 refer the reader to the Introduction to the Study of Experimental 

 Medicine for the development of the reasons, hardly questioned 

 to~day, which led to the adoption of this determinism. 



Consequently, in first approximation, it can be said that all 

 vital phenomena are dependent on the laws of energetics, and 

 in particular, on the Carnot-Clausius law. They consequendy 

 contribute to the increase in entropy of the system of which 

 living beings are a part, just as all the other phenomena 

 resorting to chemistry and physics. 



On the other hand, the majority of vital phenomena take 

 place under conditions bordering on a state of equilibrium, 

 which ordinarily leaves the choice between several diflferent 

 isodegradating paths. This second proposition puts in 

 evidence the fact that living matter, in its evolution, obeys 

 a law which is not implicitly contained in the second principle 

 of thermo-dynamics. This important point has not escaped 

 famous observers, for its trace is found in an article by Lord 

 Kelvin, in another by von Helmholtz, in the works of Ch. 

 E. Guye,^ and of H. FreundUch. 



If it is necessary to possess a thorough knowledge of 

 the chemistry of living matter which alone can instruct the 

 physiologist and the medical man as to the nature of the 

 basic reactions of the phenomena which they are interested 



^ See Ch. E. Guye, VEvolution physico-chimtque^ Chiron, Paris, 

 1922. 



