beegson's philosophy of the organism. 13 



or else that the whole problem is a transcendental one. 

 Now we are by nature disinclined to " give it up " in 

 this way, and so we are forced into metaphysics. 



But we have also to note that physicists impose 

 limitations on the scope of the second law. In the first 

 place it applies only to material masses within certain 

 limits of size : really it is valid only when we consider 

 particles of the size of the " differential elements " of 

 the mathematician, that is particles which- are very much 

 smaller than material bodies which we can experiment 

 with, but very much larger than a single molecule — 

 which contain in fact very great numbers of molecules. 

 It is only when the masses considered are very small 

 that the methods of mathematical physics apply ; and on 

 the other hand the physical treatment of individual 

 molecules would lead to entirely different results. The 

 results of thermodynamics are, in fact, statistical ones, 

 and in speaking of the properties of molecules we really 

 speak of their mean properties — that is mean kinetic 

 energy, mean free paths, and so on. Further, the great 

 physicists, such as Clerk Maxwell and Kelvin, have 

 expressly excluded living bodies from the operation of 

 the second law. 



If then we are to adopt a mechanistic theory of life, 

 we must show that the processes of the organism conform 

 to both laws of energetics. Now there can be no doubt 

 that the law of conservation does so apply. It is possible 

 to study the metabolism of an animal by measuring the 

 energy value of the substances eaten by it during a 

 certain period, and also that of the substances excreted 

 during the same experiment. We find a deficiency, for 

 less energy is contained in the egesta than in the ingesta, 

 but this deficiency is made good by the mechanical work 

 done by the animal, and by its heat loss during the 



