4o8 



ANTIENT METAPHYSICS. 



Book V. 



ciple, Hcraclitus, and ibme other anlient philofophcrs, have, I think, 

 very W'ell typified by the fymbol of Fire : fij}., becaufe Fire is the 

 moll fubtile of all the Elements, and, in that refpcdl, therefore, 

 comes the neareft to Mind of all Material Subftances ; fccoiidly^ be- 

 raufe, like Mind, it pervades all Bodies, not ading upon their fuper- 

 ficies only, but upon their inmoft particles, and therefore dilating all 

 Bodies more or lei's. 



Further, I think I have fhown. That, if Mind be the Moving 

 Power of the Planets, and if Mind can only move Body by animat- 

 ing it, it is impoffible to fuppofe that the fame Planet fliould be 

 animated by two minds moving it different ways, and That, there- 

 fore, the Motion of the Planets is perfedly fimple and uncom- 

 pounded. 



It now only remains that I endeavour to perform the promife I 

 have made, to fhow that Sir Ifaac's fyftem of Aftronomy may be 

 fupported, without fucli pojlulata and arbitrary fuppofitions, fome 

 of which are impoffible to be true, fuch as that of a Body, once fet 

 in Motion, going on to all eternity, without the agency of either 

 Body or Mind j and others of them are fuch, as no philofopher can 

 fee any reafon to admit. 



Before I enter upon this argument, it is proper to remove a pre- 

 judice which will naturally occur to every reader, that a man who 

 profeffes to know no more than the Elements of Geometry *, and 

 who knows ftill lefs of Aftronomy, fhould pretend to explain the 

 ■principles of fuch a fcience as Sir Ifaac Newton's Aftronomy, 

 ■which to underftand perfeQly, requires the greateft knov/ledge in 

 Geometry and Meclianics : And, indeed, if thofe principles were to 



be 



* Vol. I. p. 268. 



