Chap. V. ANTIENT METAPHYSICS. 109 



a lower Genus ; t'ae Beauty of a fingle Propofition is not fo great 

 as the Beauty of feveral Propofitions, fo connected together as to 

 make one Denionftration ; and the Beauty of one Demonftration is 

 not fo great as the Beauty of many, forming one Syftem of Science. 



It may not be improper here to obferve the very great difference 

 betwixt Senfations and Ideas. A Senfation does no more than ad- 

 vertife us that fome material thing exifts, of which we learn, by our 

 Senfes, certain qualities, that are ufeful or pernicious to the Animal 

 Life: Whereas an Idea feparates the Form from the Matter, and, by 

 that means, lets us know the nature of the Thing ; for every Idea 

 includes the Definition of the Thing, and virtually contains the Ge- 

 nus, Species, and Difference, which the Definition does no more 

 than unfold. 



It may alfo not be improper to obferve, in pafling, the great uti- 

 lity of a ftudy too much negledled at prefent ; I mean Logic. Many 

 people, I know, are apt to imagine, fome French writers particularly, 

 whom I have read, that Genus, Species, and Difference, are no 

 more than terms, that we have invented to exprefs the notions of 

 our Minds ; and that they have nothing to do with the Nature of 

 Things. But the truth is, they have as real an exiftence as the 

 Things thcmfelves, denoting the Nature and Eflence of the Things, 

 as far as it is poffible for us to comprehend them. 



Thus, it appears that there is no Beauty without Syftem ; and, 

 wherever there is Syftem, there is Beauty. 



Of a kin to the Beautiful is the Good^ an Idea which we will next 

 endeavour to develope. — The general Idea of Good is that, which is 

 conducive to Happinefs, that is, to the pleafure of a Senfitive 

 Being ; for fo I define Happinefs. But here we muft carefully di- 



ftinguiflx 



