CHAP. IV.] THE DOCTRINE OF CONFUTATIONS. 205 



supposed to bo received by consent, and exempt from 

 question, whilst the invention of middle terms is freely per 

 mitted to the subtilty and investigation of the wit. This 

 reduction is of two kinds, direct and inverse. It is direct 

 when the proposition itself is reduced to the principle, 

 and this is called ostensive proof: it is inverse when the 

 contradictory of the proposition is reduced to the contra 

 dictory of the principle, which they call proof by absurdity : 

 but the number or scale of the middle term is diminished, 

 or increased, according to the remoteness of the proposition 

 from the principled 



Upon this foundation we divide the art of judgment nearly, 

 as usual, into analytics, and the doctrine of clenches, or con 

 futations ; the first whereof supplies direction, and the other 

 caution : for analytics directs the true forms of the con 

 sequences of arguments, from which, if we vary, we make a 

 wrong conclusion. And this itself contains a kind of clench, 

 or confutation ; for what is right shows not only itself, but 

 also what is wrong. Yet it is safest to employ clenches as 

 monitors, the easier to discover fallacies, which would other 

 wise ensnare the judgment. We find no deficiency iu 



this newsubject the middle term may be affirmed of the original subject 

 with which he set out, he concludes that its inseparable attribute must 

 also belong to it. If these two primary propositions, viz. those which 

 affirm the attribute of the middle term, and connect this term with the 

 original subject, need proof, he is obliged to seek other middle terms, 

 and employ them in the same manner, until he establish his disputed 

 premises on the basis of experience or consentaneous principles. If 

 such fundaments, common to the minds of the disputants, do not 

 exist, the argument is nugatory, and rational conviction impossi 

 ble. Ed. 



d For no proof can be considered conclusive, unless the conclusion he 

 an immediate consequence from the propositions which involve the 

 last middle term. Now, if the proposition we seek to establish be par- 

 ticular (singular), and the principle from which we set out general 

 (universal), it is clear thnt, to connect principle and consequent, we 

 must either climb gradually from principles less general to ones more 

 enlaiged, until we reach a proposition which connects the last consequent 

 with the general principle in question ; or we must descend by a similar 

 gradation from principles less general to others more particular, 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 wbi -fa separates the 

 l&amp;gt;riiu .ii)lf ana consequent. AVi 



