EVOLUTION THE MASTER-KEY 



the conservation of energy is strictly applicable 

 to those nervous phenomena which, so far as we 

 know, always accompany the phenomena of mind. 

 The writing of Hamlet was associated and neces- 

 sarily so with certain nervous changes and move- 

 ments, which necessitated the combustion and de- 

 composition of a certain amount of food. Though 

 we cannot estimate the weight of Hamlet, as com- 

 pared with that of, say, "Charley's Aunt," we can 

 positively say that it could not have been produced 

 without the manipulation by the nervous system 

 of a certain amount of what the physicist calls 

 energy; and it is quite certain that no iota of this 

 entity the use of which is necessary in the pro- 

 duction of even the most ideal and intangible 

 mental products, such as an ode of Shelley's or a 

 myth of Plato's was either lost or created in the 

 process. Thus, without denying the existence of 

 mind, we may assert that the physical doctrine 

 of the conservation of energy, though apparently 

 confined to the phenomena of not-mind, is yet 

 to be reckoned with even in the realm of mind. 

 We therefore need not be concerned that quanti- 

 tative estimations of consciousness have not yet 

 been made as, indeed, in the nature of the case 

 they cannot be made; but we may rest content 

 that the doctrine of the conservation of energy is 

 not only the most exact and the surest upon which 

 any philosophy has ever been built, but is also 

 adequate to bear the weight of the magnificent 

 structure which has been reared upon it. 

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