ADVANCEMENT OF LEARNING 237 



is called ostensive proof: it is inverse when the contradic 

 tory of the proposition is reduced to the contradictory of the 

 principle, which they call proof by absurdity: but the num 

 ber or scale of the middle term is diminished, or increased, 

 according to the remoteness of the proposition from the 

 principle. 4 



Upon this foundation we divide the art of judgment 

 nearly, as usual, into analytics, and the doctrine of elenches, 

 or confutations; the first whereof supplies direction, and the 

 other caution: for analytics directs the true forms of the 

 consequences of arguments, from which, if we vary, we 

 make a wrong conclusion. And this itself contains a kind 

 of elench, or confutation; for what is right shows not only 

 itself, but also what is wrong. Yet it is safest to employ 

 elenches as monitors, the easier to discover fal]acies, which 

 would otherwise insnare the judgment. We find no defi 

 ciency in analytics; for it is rather loaded with superfluities 

 than deficient. 6 



We divide the doctrine of confutations into three parts; 

 viz., 1. The confutation of sophisms; 2. The confutation of 

 interpretation; and 3. The confutation of images or idols. 

 The doctrine of the confutation of sophisms is extremely 

 useful: for although a gross kind of fallacy is not improp 

 erly compared, by Seneca, to the tricks of jugglers, 8 where 

 we know not by what means the things are performed, but 



4 For no proof can be considered conclusive, unless the conclusion be an 

 immediate consequence from the propositions which involve the last middle 

 term. Now, if the proposition we seek to establish be particular (singular), and 

 the principle from which we set out general (universal), it is clear that, to con 

 nect principle and consequent, we must either climb gradually from principles 

 less general to ones more enlarged, until we reach a proposition which con 

 nects the last consequent with the general principle in question ; or we must 

 descend by a similar gradation from principles less general to others more par 

 ticular, until we reach the proposition which affirms the last consequence of 

 the particular conclusion. The number, therefore, of these intermediate links, 

 must augment or diminish in proportion to the interval which separates the 

 principle and consequent. Ed. 



5 Upon the subject of analytics, see &quot;Weigelius in his &quot;Analysis Aristotelica, 

 ex Euclide restituta;&quot; andMorhof in his &quot;Poly his tor.,&quot; torn. i. lib. ii c. 7, de 

 Methodis variis. 

 6 Epist. 45, c. 7. 



