286 THE FITNESS OF THE ENVIRONMENT 



composition from organic chemistry, through 

 the actual successes of the laboratory in new 

 syntheses; and the final recognition, based 

 upon understanding of the principle of the 

 conservation of energy, that, whatever else 

 "vital force" may be, it is certainly not 

 force, — a form of energy. Thus limited, 

 vitalism has been obliged to take refuge in a 

 more restricted belief; namely, that the organ- 

 ism is somehow governed by a directive 

 tendency which, like an architect, presides 

 over its development ; but that meanwhile the 

 manifold processes of life and evolution go on 

 within the world of physical science just as 

 the work of the builder conforms to the laws 

 of mechanics, though following the plan of the 

 architect. 



This view has been well stated by another 

 great Frenchman, Claude Bernard: "Life 

 is the directive idea or evolutive force of the 

 being ; . . . but it would be an error to believe 

 that this metaphysical force operates after 

 the manner of a physical force. . . . The 

 metaphysical evolutive force by which we 

 may characterize life is useless to science, 

 because, existing apart from physical forces, 

 it can exercise no influence upon them. Hence 

 we must here separate the world of meta- 

 physics from the world of positive phenomena 



