RESULTS OF LIFE 251 



bodies ; it finds its origin in the exciting cause of vital movements. 

 Now this cause, which in living bodies may give rise to the force in 

 question, could not produce it in crude or lifeless bodies, nor could 

 it animate them, even though it acted upon them to the same 

 extent. 



Moreover, the force in question does not altogether withdraw 

 the various parts of living bodies from the sway of chemical affinity ; 

 and M. Richerand himself agrees that there occur, in the living 

 machinery, effects that are quite obviously chemical, physical, and 

 mechanical ; but these effects are always influenced, modified, and 

 weakened by the forces of life. To M. Richerand's reflections on this 

 subject I may add the remark that the decompositions and alterations 

 produced in living bodies by chemical affinities which tend to break 

 up the state of things adapted for the maintenance of life, are incessantly 

 being repaired, although more or less completely, by the results of 

 the vital force which acts on these bodies. Now in order to bring 

 this vital force into existence and endow it with its recognised properties, 

 nature has no need of special laws ; those which control all other 

 bodies are amply sufficient for the purpose. 



Nature never uses more complex methods than necessary : if it 

 was possible for her to produce all the phenomena of organisation 

 by means of the laws and forces to which all bodies are universally 

 subjected, she has doubtless done so ; and did not create laws and 

 forces for the control of one section of her productions, opposite to 

 those that she uses for the control of the rest. 



It is enough to know that the cause, which produces the vital force 

 in bodies whose organisation and structure permit that force to exist 

 and excite the organic functions, could not give rise to any such 

 power in crude or inorganic bodies, where the state of the parts does 

 not permit of the activities and effects observed in living bodies. This 

 cause, of which I have just spoken, only produces in the case of crude 

 bodies or inorganic substances a force which incessantly works towards 

 their decomposition, and which regularly achieves it by mingling 

 its effects with that of the chemical affinities, when the closeness of 

 their combination does not prevent it. 



There is then no difference in the physical laws, by which all living 

 bodies are controlled ; but there is a great difference in the circum- 

 stances under which these laws act. 



The vital force, we are told, keeps up a perpetual struggle against the 

 forces which lifeless bodies obey ; and life is only a prolonged combat 

 between these different forces. 



For my own part, I see in both cases only one force, which is synthetic 

 in one order of things and analytic in another. Now since the conditions 



