63 ANTIENT METAPHYSICS. Bookll. 



and Deity mud be fo far dependent upon it, as to derive from it all 

 his knowledge. 



It is, therefore, of the greateft importance in Theology, and the 

 religion of Nature, as well as in the philofophy of Mind, to be able 

 to diftinguifh accurately betwixt Ideas and Senfations. 



There are fome ideas, which, I think, it mufl; be evident to every 

 Body, are not Senfations, fuch as the Ideas of bein^ or exi/lence, of 

 the fame, or different, of like or unlike^ of number, that is, 7miltitiule 

 defined, of beauty, goodnefs, truth, and fcience \ for by what fenfe 

 can any of thefe be apprehended ? Is it by the fight, the hearing, 

 the touch, the tafte, or the fmell ? Is it by any, or all of thefe ? 

 No body, I think, will fay that it is ; for, though we perceive, by 

 the fenfe, objeds thatexift, — that are like or unlike to other objeds, 

 — that are beautiful, — that are number, 8cc. yet we certainly do not 

 perceive by the fenfe the ideas of Exiftence, Likenefs, Beauty, Num- 

 ber, &c. And, if they are not perceptions of the fenfe, or fenfa- 

 tions, they muft be Ideas ; for every thing we perceive is neceflarily 

 the one or the other. 



It is by thefe ex;amples, that Plato, in the Theaetetes, has fhown 

 the difference betwixt Senfations and Ideas. The former, fays he, 

 the Mind perceives by the Body, and its organs ; the other it per- 

 ceives by itfelf, without any afliflance from the Body *. He might 



have 



* Plato Thaetet. .p 84. editio Serraui. The Greek fcholar will obferve in this 

 paflage of Plato a diftin^lion, which is fomewhat nice, betwixt • the Relative in 

 the dative cafe, and Ji' Jk, the genetive with the prepoGtion a** ; the former figni- 

 fying the Agent, or the Percipient, in this cafe, the other the Inftrument by which 

 xhe percipient perceives. Thus we perceive all the objedls of fenfe, fuch as co- 

 lours, fineUs, taftes, tj ^|'w;^;;1, or by the Mind j but we perceive each of them bj 



the 



