96 CREATIVE EVOLUTION [chap. 



a Serpula, or the slightly differentiated eye of the Alciope, 

 or the marvelously perfected eye of the bird ; but all these 

 organs, unequal as is their complexity, necessarily present 

 an equal coordination. For this reason, no matter how 

 distant two animal species may be from each other, if the 

 progress toward vision has gone equally far in both, there 

 is the same visual organ in each case, for the form of the 

 organ only expresses the degree in which the exercise of 

 the function has been obtained. 



But, in speaking of a progress toward vision, are we 

 not coming back to the old notion of finality? It would 

 be so, undoubtedly, if this progress required the conscious 

 or unconscious idea of an end to be attained. But it is 

 really effected in virtue of the original impetus of life; 

 it is implied in this movement itself, and that is just why 

 it is found in independent lines of evolution. If now we 

 are asked why and how it is implied therein, we reply 

 that life is, more than anything else, a tendency to act on 

 inert matter. The direction of this action is not prede- 

 termined; hence the unforeseeable variety of forms which 

 life, in evolving, sows along its path. But this action 

 always presents, to some extent, the character of con- 

 tingency; it implies at least a rudiment of choice. Now 

 a choice involves the anticipatory idea of several possible 

 actions. Possibilities of action must therefore be marked 

 out for the living being before the action itself. Visual 

 perception is nothing else: 1 the visible outlines of bodies 

 are the design of our eventual action on them. Vision 

 will be found, therefore, in different degrees in the most 

 diverse animals, and it will appear in the same complexity 

 of structure wherever it has reached the same degree of 

 intensity. 



We have dwelt on these resemblances of structure 



1 See, on this subject, Mature et m&moire, chap. i. 



