Chap. VII. AN TIE NT METAPHYSICS. 



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led in Greek hiavota, in Latin difcurfus mentis, and in Engllfh Rea' 

 fonhig ; or, as the Latin expreffion may not be improperly tranflat- 

 ed, Difcoiirfe of Re nf on. And the way, in which the two terms are 

 conneded by the middle term, is this. If the predicate, or greater 

 term of the propofition to be proved, contain the middle term, and if 

 the middle term contain the fuhjed, or leffer term, then the predicate 

 muft necefTarily contain the fubject; and thus an affirmative propor- 

 tion is proved. But, on the other hand, if the predicate do not con- 

 tain the middle term, but the middle term contain the leffer term of 

 the propofition to be proved, then it is proved that the predicate does 

 not contain the fubjod ; and this is the demonftratioa of a negative 

 propofuioB. 



But fuppole two propofitions, by which we apply the middle 

 term firft to one idea of the propofition to be proved and then to 

 the other, are not fufficient to difcover the connedion of the two 

 propofitions; what is then to be done? And I fay, more propo- 

 fitions muft be difcovered, by which the two terms of the propo- 

 fitions to be proved are to be conneded together. But is this to go 

 on in infinitum f If this were the cafe, there could be no demon- 

 ftraiion, or fcience of any kind ; for, if every thing was to be prov- 

 ed, nothing could be proved. There muft, therefore, be fome pro- 

 pofitions, which require no proof : Thefe are called flA:/o77ZJ or felf- 

 evident propofitions ; in which, by the fame faculty that enables us 

 to form ideasj I mean the intelled, we difcover the neceffary con- 

 nedion betwixt the two terms*. 



. And here it is evident, that before we can arrive at felf-eviJenE 

 propofitions, many other propofitions muft be formed, and all thefe 

 muft be arranged, and put together in fuch an order as to make de- 

 monftration or fcience. To know how to do this is itfelf a great 

 fcience ; the greateft, I think, that ever was difcovered by man. 



2K 'it 



* See, upon the fubject of AxiomS; vol. I. p. 383, and following. 



