The Evolution of the Sciences 



of life belong to brute matter and derive from 

 physico-chemical causes. 



The living being is characterised by its pro- 

 ducts, by its organisation and by its functions. 

 Let us first consider its products. It was long 

 believed that organised beings elaborated and 

 utilised special products. It was the custom 

 to speak of Nature's mysterious laboratory 

 and of a vital force different from and additional 

 to the forces which determine ordinary chemical 

 phenomena. All chemists, and all naturalists, 

 at the beginning of the nineteenth century, 

 still held this " vitalist " doctrine, and Berzelius 

 was able to write in his classical Treatise of 

 Chemistry: " In animated nature the elements 

 seem to obey entirely different laws from those of 

 inorganic nature ... If we could discover the 

 cause of this difference we should have the key 

 to organic chemistry; but this cause is so 

 completely hidden that we have no hope of 

 discovering it, at least in our day." 



We all know how vitalism has retreated 

 before the valiant attack of a legion of chemists 



with M. Berthelot at their head. Little by 



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