132 Measurement of Belief. [CHAP. vi. 



express understanding that we do not guarantee its accuracy. 

 Our belief in some single events, for example, might be cor 

 rect, and yet that in a compound of several (if derived merely 

 from our instinctive laws of belief) very possibly might not 

 be correct, but might lead us into practical mistakes if we 

 determined to act upon it. Even if the two were in accord 

 ance, this accordance would have to be proved, which would 

 lead us round, by what I cannot but think a circuitous 

 process, to the point which has been already chosen for 

 commencing with. 



12. De Morgan seems to imply that the doctrine 

 criticised above finds a justification from the analogy of 

 Formal Logic. If the laws of necessary inference can be 

 studied apart from all reference to external facts (except 

 by way of illustration), why not those of probable inference ? 

 There does not, however, seem to be much force in any such 

 analogy. Formal Logic, at any rate under its modern or 

 Kantian mode of treatment, is based upon the assumption 

 that there are laws of thought as distinguished from laws of 

 things, and that these laws of thought can be ascertained and 

 studied without taking into account their reference to any 

 particular object. Now so long as we are confined to neces 

 sary or irreversible laws, as is of course the case in ordinary 

 Formal Logic, this assumption leads to no special difficulties 

 We mean by this, that no conflict arises between these sub 

 jective and objective necessities. The two exist in perfect 

 harmony side by side, the one being the accurate counter 

 part of the other. So precise is the correspondence between 

 them, that few persons would notice, until study of meta 

 physics had called their attention to such points, that there 

 were these two sides to the question. They would make 

 their appeal to either with equal confidence, saying indiffer 

 ently, the thing must be so, or, we cannot conceive its being 



