Chap. VII. ANTIENT METAPHYSICS. 49 



moves Body ; for I think I have fhown, that we not only know 

 negatively that it docs not move Body, as Body moves Body, but 

 pofitively in what manner it moves it. It is true, indeed, that, as 

 we do not know the Subftance of either, we cannot tell exadly how, 

 by their nature and eflence, they are fo conned:ed, that the one muft 

 be always adlivc, and the other always paflive : Nor can we ac- 

 count how Subftances, fo totally different in their natures, fhould af- 

 fedl one another as we know they do. But, 



Efl quoJam prodire tenus, fi non datur ultra * ; 



And we muft give over altogether the purfuit of knowledge, if we 

 infift to know the very eflence of things, and their moft hidden 

 principles: All that we fhould endeavour, is to know well what is gi- 

 ven us to know, and to live in hopes that our knowledge Ihall be 

 .more perfed in a more perfedl ftate. 



Vol. TI. G BOOK 



• Horat. lib. I. ep. i. v. 32. 



