Organisms and Their Origin 125 



The living creature feeds and grows; it undergoes 

 ceaseless change, yet has a marvellous power of re- 

 taining its integrity; it is not merely a self-stoking, 

 self -repairing engine, but a self-reproducing en- 

 gine; it has a self-regulative development; it gives 

 effective response to external stimuli; it profits by 

 experience; it uses time; it coordinates its activ- 

 ities into unified behavior, it may be into intelligent 

 deeds and rational conduct. Allowing for the 

 gradual realization of potentialities in the course 

 of evolution, we cannot but feel that if the living 

 emerged from the not-living, then our appreciation 

 of not-living matter must be greatly enhanced. 

 As a matter of fact, however, we cannot at present 

 redescribe any vital behavior in terms of physical 

 and chemical categories, and the secret of the or- 

 ganism has to be admitted as such whether we ad- 

 vance to a vitalistic statement of it or not. In 

 vitalistic doctrine we must distinguish two posi- 

 tions, first, the negative statement, which seems at 

 present safe, that no vital activity can be com- 

 pletely redescribed in terms of physics and chem- 

 istry, and second, the positive statement, which is 

 open to various objections, that there is in the 

 living creature some 'vital principle" or "En- 

 telechy." 



If an Organism Could be Made Artificially, What 

 Then? Finally, let us suppose that some bold ex- 

 perimenter in the borderland between chemistry 



