Chap. VI. A N T I E N T M E T A P H Y S I C S. 425 



choofes to call ideas, would necefTarily refemble the objeds which we 

 perceive, otherwiie we could not know that we perceive them : And 

 therefore our perception of a JoluU extended^ a fweet or bitter ob- 

 jed, muft be folid, extended, fweet, or bitter. This argument, I fay, 

 when attended to, proves nothing at all, and is really altogether unin- 

 telligible ; for, when we confider that the perceptions of fenfe are 

 produced by the preflTure of external objeds upon the organs of fenfe, 

 which being from thofe organs communicated, to the mind, caufes 

 therein a certain perception, that we caWjenfat'ton^ it is impoffible 

 to conceive how the perception or affedion of the mind fhould re- 

 femble the objed by which it is affected. We might as well con- 

 ceive, that the fenfation that we have from the prick of a fword 

 fhould refemble the fword. 



But, if Mr Hume had not confounded, as he every where does, the 

 perceptions of fenfe with the ideas of intelledt, he would have k^n. 

 that there was a very great difference betwixt the perceptions them- 

 felves, and the ideas thence formed, and that there is fome ground for 

 Mr Lookc's diflindion betwixt the primary and fecondary qualities 

 of body ; for it is the bufinefs of intelled to inveftigate the nature of 

 things, and to find out the/pecies or idea in the material form. Now, 

 in certain objeds perceived by the fenfe, it can do that with great ac- 

 curacy. For example, with refped to its perception of exteiifion and 

 fgure^ it can diftinguiOi length, breadth, and depth ; and all the fe- 

 veral figures, by which body is bounded, it can fcparate and difcri- 

 minate one from another ; and there can be no reafon to doubt but 

 that thefe ideas, thus formed, havei their models and archetypes in the 

 nature of things, and that the bodies thus bounded are the very ob- 

 jeds which affed our fenfes of feeing and touching. And according- 

 ly, we find that the fcience which we form of thofe ideas, ap})lies per- 

 fedly well to all bodies. It is the fame with regard to the ideas 

 which we form from the perceptions of the fenfe of hearing ; for of 



H h h founds 



