364 THE RELATION OF MIND TO BODY 



unable to measure feeling in this way to say that a certain 

 feeling arises in relation to a certain part of the brain when there 

 is a certain expenditure of energy in the latter. Consequently 

 merely because we cannot measure feeling in this way it has 

 been argued, in effect, that there is no connexion between the 

 two. A vast amount of nonsense has been written on this basis. 

 For example, we are told that the thoughts of a Shakespeare and 

 those of an imbecile bear no relation to the amount of energy 

 respectively expended by them. Here the excellence of the 

 thinking, as excellence is estimated by us, is taken as a criterion, 

 and it is assumed that the greater the excellence the greater 

 should be the expenditure of energy. The assumption is obviously 

 absurd as absurd as if it were argued that, because good and bad 

 railway engines give different results, therefore the expenditure of 

 coal has nothing to do with their movements. Moreover, this 

 hypothesis, that sensation and thought and the concurrent 

 expenditure of energy, bear no proportion to one another, is 

 contrary to the universally accepted belief that every mental 

 change, every feeling, is correlated with a brain change ; for it is 

 not denied by any one that cerebral changes, like other physical 

 events, result from, and are proportionate to, the expenditure. It 

 is certain that feeling is unknown to us except in connexion with 

 the work of nervous tissue. But, since the conditions under which 

 the expenditure occurs are but little known, we cannot estimate 

 the amount of it in terms of feeling ; and, apparently, because our 

 perceptive powers are limited^ we are unable to conceive how the 

 working of the brain gives origin to mind. 



605. Of course, as just indicated, mind may be considered as 

 comparable, not to the music that proceeds from the instrument, 

 but to the player who plays on it. But this hypothesis of an 

 independent agent seems, at least, unnecessary. We shall see 

 immediately that there is convincing evidence that mind is a 

 product of evolution. As a function of nervous tissue, we can 

 conceive of it as coming gradually into being under the influence 

 of natural selection. Or rather, we can conceive the brain as 

 evolving and becoming capable of doing more and more varied work, 

 just as we can conceive the hand as so evolving. But, if we think 

 of mind as an independent player who operates on the brain, and 

 so directs the activities of the body of which the brain is a part, 

 how shall we account for the existence of this player ? Is there a 

 definite amount of mind in the universe as there is of substance 

 and energy, and is he somehow evolved out of this fund ? Is a 



