SCIENCE AND DEMONSTRATION 219 



analyse the conditions or antecedents of a concrete, actual fact or 

 phenomenon, sufficiently to be compelled by the evidence to pro 

 nounce categorically that it will recur. 



Truths for which we have necessary or cogent evidence 

 &quot; necessary &quot; or &quot; metaphysical &quot; truths are all abstract : they 

 formulate relations between aspects of reality apart from their 

 existence or happening. * Even when categorical in expression, as 

 e.g. &quot;Triangles inscribed in semicircles are right-angled,&quot; they 

 are conditional in thought (134-5) as regards the actuality of their 

 antecedents. The logical necessity of these relations between 

 subject and predicate is the necessity by which any abstract 

 object of thought is identical with itself, with all that the mind 

 apprehends in it. It is a necessity that pertains to the abstract 

 essences of things. So long, therefore, as we deal with purely 

 abstract judgments, such as those of mathematics, we can analyse 

 the grounds for the abstract relations we establish, and can see 

 these to be cogent Such truths are called &quot;necessary,&quot; because 

 they express essentially or intellectually necessary relations be 

 tween abstract objects of thought. But when we deal with general 

 izations about concrete, existing things, beyond actual sense ex 

 perience, our analysis must always leave an unknown and uncertain 

 residue, that, namely, which is the ground for the persistence 

 through the changing conditions of time and space of the 

 elements about which we are thinking. For truths, therefore, 

 which imply the actual existence, beyond experience, of the 

 elements of reality to which they refer, the ground or evidence 

 can never be cogent, can never necessitate our assent. These are 

 called, and rightly called, &quot;contingent&quot; truths, because they make 

 such mental assertions about things as will hold good only if 

 those things persist in the concrete existence and activity with 

 which we know them to have been endowed within our experi 

 ence. 



Of course, if we express this assumption about their persistence, in formu 

 lating &quot; a general judgment concerning natural phenomena &quot; a that is, a 

 judgment affirming their universal repetition throughout all time and space 

 whenever and wherever all the conditions of our hypothesis are verified, we 



1 They are &quot; altogether independent of any physical process. In some cases we 

 see that certain concepts, statically considered, stand in a relation of identity (or 

 difference) under pain of a contradiction in terms. ... In other cases a causal 

 relation is involved in the very nature of the abstract concept, apart from any dynamic 

 efficiency.&quot; JOYCE, op. cit., pp. 238-9. C/., however, p. 215, n. i. 



3 WELTON, ibid., p. 205. 



