228 FROM FISH TO PHILOSOPHER 



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13. Olmsted, J. M. D., and E. H. Olmsted. Claude 

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Claude Bernard first used the word milieu to indicate 

 the blood plasma as the environment in which the in- 

 dividual Hves— as opposed to the external environment 

 —in his lecture notes of 1857, and the concept of the 

 constancy of this environment was developed at some 

 length in his essays of 1859 {1}. He later expanded the 

 idea in his Phenom^nes {2}, using the terms milieu irir- 



