NUTRITION. • 229 



arrested. Its suspension involves ipso facto ihe sus- 

 pension of life itself. It is, in the words of Claude 

 Bernard, that property of nutrition " which, as long as 

 it exists in an element, compels us to believe that this 

 element is alive, and which, when it is absent, compels 

 us to believe that it is dead. It dominates all others 

 by its generality and its importance. In a word, it is 

 the absolute test of vitality." 



Biological Energetics shows the Importance of 

 Nittrition. — We have indicated in advance the reason 

 of its importance, showing that its two phases, cjis- 

 assimilation and assimilation, are the energetic 

 condition of the two kinds of vital phenomena 

 which we can distinguish. 



Nutrition is a manufacture of protoplasm at the 

 expense of the materials of the cellular ambient 

 medium, which are assimilated — i.e., made chemically 

 and physically similar to living matter and to the 

 reserves it stores up. This operation, which is 

 peculiarly chemical, is therefore indicated by the 

 borrowing of materials from the external world, a 

 borrowing which is always going on, because the 

 operation is permanent, and,, let me add, because of 

 the continual rejection of the waste products of 

 this manufacture. Our formula is : — Nutrition is a 

 chemistry which persists. 



The Idea of the Vital Vortex is Erroneous. — Here 

 the effect has hidden the cause from the eyes 

 of the biologists. They have been struck by the 

 incessant entry and exit, by the never-ceasing passage, 

 by the cycle of matter through the living being 

 without guessing its why and wherefore ; and they 

 have taken as a picture of the living being a vortex 

 in which the essential form is maintained while the 



