THE PHYSICAL BASIS OF LIFE 



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formally to define 'life' or 'protoplasm' because, since they are 

 unique, it is impossible to resort to the trick of comparing them 

 with something else ; and because the expressions ' protoplasm ' and 

 'life' are generalizations. The former indicates that all animals 

 and plants have an essentially similar foundation, and the latter 

 that they exhibit certain characteristic actions and reactions. The 

 living organism exhibits a permanence and continuity of individ- 

 uality correlated with specific behavior, and this it transmits to 

 other matter which it makes a part of itself, and to its offspring at 

 reproduction. The organism regarded as a whole is, indeed, a 

 unique phenomenon : one whose fundamental nature is as essential 

 as any of the concepts of physics. 



