194 ETHICAL ASPECTS OF EVOLUTION 



of the impulses which make up his character. Nor is the 

 character of each individual the same at all periods of his 

 life ; the pleasures of youth are not the same as those of 

 manhood, or those, as the pleasures of old age. The boy 

 prefers a pantomime, the old man a tragedy, and there 

 are others who are not greatly interested in any form of 

 dramatic representation. A measured scale of the com 

 parative intensities of conflicting pleasures would hold 

 good only for the individual whose feelings were the im 

 mediate objects of measurement ; with no others would 

 similar measurements yield exactly the same results, and 

 in a large number of cases the divergencies would be 

 enormous. A general scale of intensities compiled from 

 the measurements of a number of individuals, would neces 

 sarily differ from the personal scale of each individual 

 among them ; and, if his object were the realization of his 

 own greatest happiness, would mislead him. The same 

 scale, practically applied in the pursuit of the greatest 

 happiness of the greatest number, would exterminate the 

 pleasures of the few, and fill their place with the pleasures 

 of the many. 



The main purpose, it may be presumed, of an exact 

 calculus of intensities would be to furnish a safe basis, 

 such as could not be impugned except by the detection of 

 errors in the calculation, for a choice between two con 

 flicting lines of conduct, each of which commended itself 

 to the understanding. It would not be required when the 

 conflict was between impulses of distinctly different ethical 

 values. In those we should certainly trust our unaided 

 subjective judgements, however decisive the figures might 

 be against them. The certainty that truth is to be preferred 

 to perjury is stronger than any that can be produced by 

 mathematical demonstration. When, however, as is often 

 the case, the competition is so close that the unaided judge 

 ment gives no certain award, measurement would no doubt 

 be of use, were it not invalidated by the considerations that, 

 even if we admitted pleasure to be the criterion, we should 

 still have to supplement the intensities with other elements 



