7« ANTIENT METAPHYSICS. Book II. 



was fixed or permanent, but that, as all thofe things which affeded 

 our Senies were in conftant motion and continually pafling away, 

 our knowledge was of the fame kind. Further, they maintained 

 that the Senfations of difter.Mi, men being very different, and of the 

 fame man at different tinico, varying, as I have faid, according to the 

 difpolition of the organ, the objed, or the medium, what was truth 

 or knowledge to one man, was not fo to another, nor to the fame 

 man at different times ; and, therefore, that every man was, at every 

 time, a flandard to himfelf of Truth and Knowledge. On the other 

 hand, the philofophers, who maintained a difference betwixt Ideas 

 and Senfations, affirmed that all our knowledge confifted of Ideas, 

 which, as they all proceeded from the Divine Mind, where were the 

 original forms of all things, the archetypes of all the forms to be (ecn 

 here below, were as permanent as the Divinity himfelf. If Mr Da- 

 vid Hume had been learned enough to have underftood the dodlrine 

 of Protagoras and Heraclitus as explained by Plato and Ariftotle, 

 he would certainly have embraced it as a neceflary confequence of 

 his dodrine of Ideas being nothing but Senfations ; and, upon that 

 foundation, would have raifed a much better fyftem of Scepticifna 

 and Infidelity than any he has produced. 



Having premifed thefe obfervations, I come now to apply this 

 diftindion, that I have made betwixt Ideas and Senfations, to parti- 

 cular cafes ; and I will begin with the Ideas of Subftances, fuch as 

 the Idea of any particular man : The outward form or material part 

 of this objedl makes an impreffion upon feveral of our fenfes : By 

 the Sight, we perceive a coloured fuperficies ; by the fame fenfe, we 

 perceive the objed in different places at different times, that is, in 

 motion ; by our Hearing, we perceive the founds that it utters ; 

 and, by the Touch, we feel that it is folid and refifting. But not 

 one of thefe perceptions, nor all put together, make the Idea of a 

 man ; for it is a miftake to imagine, that the Idea of any thing is 

 nothing but a colledtion of the feveral fenfations which it produces. 

 From thefe, indeed, the Idea may arife, bilt they are not the Idea 



itfelf, 



