420 ANTIENT METAPHYSICS. Book V. 



But it would be vain to ufe fuch an argument againft Mr Hume, be- 

 caufe it fuppofes a firft caufe, in the mind of which the idea of every 

 thing poflible exifts, and, for that reafon, is a^ually produced, as we 

 cannot conceive any idea in the mind of fuch a being that is not 

 brought into energy and a&uality ; for otherwife it v^^ould be there in 

 vain. But this is a philofophy altogether out of fight of fuch philofo- 

 phers ; We mufl:, therefore, in arguing with them, endeavour to 

 prove, in fome other way, that there is fomething material exifting, 

 which produces our fenfations. 



But what fort of proof are we to ufe againft men who deny that 

 there is fuch a thing as truth, or even that there is one thing more 

 probable than another ? But, 1 think, I can convince others, if not 

 them, from a principle which they themfelves have unwarily admit- 

 ted, namely, the principle of conjcioufnefs^ by which they fay they are 

 convinced that they have perceptions ; for, if Mr Hume had carried 

 his fcepticifm fo far, as to difpute that he had even perceptions, it 

 would have been impoffible to have proved, at leaft upon his prin- 

 ciples, that there was fuch a thing as body. But he admits that he 

 is a bundle of perceptions. And the argument from thofe percep- 

 tions againft him, for the exiftence of matter^ is fo much the fair- 

 er, that, from thofe very perceptions, he argues againft the exiftence 

 of matter ; for, fays he, we know nothing of material objecls, but by 

 our ideas of them. Now, our ideas are not folid, extended, or figu- 

 red ; therefore it is impoflible that we can know that there are any 

 fuch fubftances. And he adds, that our own philofophy, meaning 

 Mr Locke's, admits, that our jierceptions of the fecondary qualities of 

 external objedls, fuch as white and black, b.tter and fweet, have no 

 exiflence in the objeds themlVlves. And, for the fame reafon, what 

 we call primary qualities, fuch as extenfion and folidity, have likewife 

 no exiftence in the objeds. 



My 



