n6 CREATIVE EVOLUTION CHAP 



the movements among which it can choose ; the 

 clearer, also, is the consciousness that accompanies 

 them. But neither this mobility nor this choice nor 

 consequently this consciousness involves as a necessary 

 condition the presence of a nervous system ; the latter 

 has only canalized in definite directions, and brought 

 up to a higher degree of intensity, a rudimentary and 

 vague activity, diffused throughout the mass of the 

 organized substance. The lower we descend in the 

 animal series, the more the nervous centres are simpli 

 fied, and the more, too, they separate from each other, 

 till finally the nervous elements disappear, merged in 

 the mass of a less differentiated organism. But it is 

 the same with all the other apparatus, with all the 

 other anatomical elements ; and it would be as absurd 

 to refuse consciousness to an animal because it has no 

 brain as to declare it incapable of nourishing itself be 

 cause it has no stomach. The truth is that the nervous 

 system arises, like the other systems, from a division 

 of labour. It does not create the function, it only 

 brings it to a higher degree of intensity and precision 

 by giving it the double form of reflex and voluntary 

 activity. To accomplish a true reflex movement, a 

 whole mechanism is necessary, set up in the spinal 

 cord or the medulla. To choose voluntarily between 

 several definite courses of action, cerebral centres are 

 necessary, that is, crossways from which paths start, 

 leading to motor mechanisms of diverse form but equal 

 precision. But where nervous elements are not yet 

 canalized, still less concentrated into a system, there is 

 something from which, by a kind of splitting, both the 

 reflex and the voluntary will arise, something which 

 has neither the mechanical precision of the former 

 nor the intelligent hesitations of the latter, but which, 



