METABOLISM 45 



ganization. In proportion as this point 

 of view prevails the differences between 

 the two schools will tend to disappear. 

 It may be said that the real problem 

 is the origin of the fit. To explain why, 

 among all the possible combinations, 

 some few are able to grow, reproduce, 

 and adjust themselves so as to assure 

 continued existence, may well be beyond 

 our present knowledge. We must per- 

 force wait for more facts before attempt- 

 ing such an explanation. But in the 

 meantime the very search for such facts 

 implies a hope that the explanation will 

 ultimately be reached and this hope is 

 in itself a great incentive to an unremit- 

 ting search for truth. 



VI 

 METABOLISM 



Let us now consider metabolism as a 

 test of life. All the chemical activities 

 of the organism are included in metab- 

 olism and they are the very essence of 



