148 CREATIVE EVOLUTION CHAP, 



nature, an infinite complexity of detail combined with a 

 marvellous simplicity of function, does at once, when 

 required, what it is called upon to do, without difficulty 

 and with a perfection that is often wonderful. In 

 return, it retains an almost invariable structure, since a 

 modification of it involves a modification of the species. 

 Instinct is therefore necessarily specialized, being 

 nothing but the utilization of a specific instrument for 

 a specific object. The instrument constructed in 

 telligently, on the contrary, is an imperfect instrument. 

 It costs an effort. It is generally troublesome to 

 handle. But, as it is made of unorganized matter, it 

 can take any form whatsoever, serve any purpose, free 

 the living being from every new difficulty that arises and 

 bestow on it an unlimited number of powers. Whilst 

 it is inferior to the natural instrument for the satisfac 

 tion of immediate wants, its advantage over it is the 

 greater, the less urgent the need. Above all, it reacts 

 on the nature of the being that constructs it ; for in 

 calling on him to exercise a new function, it confers on 

 him, so to speak, a richer organization, being an artificial 

 organ by which the natural organism is extended. 

 For every need that it satisfies, it creates a new need ; 

 and so, instead of closing, like instinct, the round of 

 action within which the animal tends to move auto 

 matically, it lays open to activity an unlimited field 

 into which it is driven further and further, and made 

 more and more free. But this advantage of intelli 

 gence over instinct only appears at a late stage, when 

 intelligence, having raised construction to a higher 

 degree, proceeds to construct constructive machinery. 

 At the outset, the advantages and drawbacks of 

 the artificial instrument and of the natural instru 

 ment balance so well that it is hard to foretell which 



