1 88 Purely directive function of Will. CHAP. 



is stored in the brain and in the entire nervous 

 system, as well as in the muscles ; and that the 

 motion of every nerve-current, as of every electric 

 current, involves the transformation of energy from 

 some other form into that represented by the 

 current. 



It may, as we have remarked before, be objected 

 that this is a similar case to that of the engineer, who 

 starts or stops his engine by a turn of his hand, 

 which is a mechanical action, involving an exertion 

 of force and a transformation of energy ; and con- 

 sequently that it brings us no nearer to understanding 

 how the actions of the muscular system, which are 

 mechanical, can be directed by the Will, which is not 

 a mechanical agency, and cannot supply energy. But 

 to this it may be replied, that, as we have seen, 

 the proportion which the muscular force exerted 

 by the engineer bears to the force of his engine, 

 may be diminished without limit, provided only that 

 it does not become absolutely null. We know 

 nothing whatever of the modus operandi of the Will 

 in determining the transformation of stored energy 

 in the brain into a nerve-current; but we are safe 

 in asserting that it bears no resemblance to that of 

 the engineer, and does not consist in anything like 

 moving a lever; and I see nothing improbable in 

 the belief that the Will may exercise its directive 

 and regulative function without the exertion of any 

 energy whatever. When man's mechanical art can 

 diminish the magnitude of the directing force infini- 



