VALUATIONS OF PLEASURE AND PAIN 127 



health and persistence of the organism require that both 

 should grow at equal rates. A deficiency of pain, with refer 

 ence to the contemporaneous development of pleasure, 

 would occasion an excessive and irregular output of energy ; 

 an excess would bring about an undue depression, and either 

 would interfere with the necessary adjustment between 

 the organism and its surroundings. It must be remem 

 bered that its operation, like that of pleasure, is impartial, 

 and that the constraint and regulation are exercised on 

 all impulses, the good and the evil alike. 



NOTE. Cf . Arist. Eth. Nic. x. 5 (trans. R. Williams, p. 304) : Each act 

 is intensified by its appropriate pleasure. It is universally true that those 

 who take pleasure in the performance of their peculiar function improve 

 their aptitude for and their skill in its performance. 



