THE ORGANIC AND THE INORGANIC 327 



becomes converted into it. Thus our ignorance of the 

 precise nature of the energy-transformations of in- 

 organic things — an ignorance which is all the while 

 disappearing — becomes the excuse for a comparison of 

 these with vital transformations, and for the assump- 

 tion that there is a fundamental similarity in the two 

 kinds of happening. 



Less is assumed in the assumption of an entelechian 

 agency than in assuming that the manifestations of 

 life are the consequences of a vital " energy-form," 

 different from inorganic forms, though belonging to 

 the same order, inasmuch as it may be concatenated 

 with these inorganic energy-forms. We need not sup- 

 pose that a particular kind of transformation occurs 

 only in the sphere of the organic : all that we need 

 assume is that, by some agency inherent in the activities 

 of the organism, chemical reactions that would occur if 

 the constellation of parts were an inorganic one are 

 suspended. Nothing unfamiliar to physical science is 

 involved in this assumption. Hydrogen and chlorine, 

 gases that combine together when mixed with the 

 production of heat and hght, may be mixed under 

 conditions such that the combination may be delayed 

 for an indefinite time. Iron which dissolves in nitric 

 acid may nevertheless be brought into the " passive " 

 form when it remains in contact with the re-agent but 

 is not dissolved by it. Enzymes which are in contact 

 with the walls of the alimentary canal do not dissolve 

 these membranes so long as the tissues are alive, and 

 they do not dissolve the food stuff until they have been 

 " activated." Oxygen which is contained in the 

 tissues does not oxidise the tissue substances until an 

 enzyme or a catalase has exerted its influence. More 

 and more, as physiology has become more searching in 

 its study of the functions of the animal, has it sought 



