4-^6 ANTIENT METAPHYSICS. Book V. 



Newtonians teach their Syjiem in an improper IVny — hjlarice of a 

 true conclufion from falfe Premiffes. — T^his applied to the Newto- 

 nians. 



ROM what has been fald in the preceding Chapters, I hope 

 -fl- the reader has learned to make the diftindtion, if he had not 

 learned it before, betwixt Philofophy and Aftronomy, or, in other 

 words, betwixt inveftigating the Laws of the Celeftial Motions, or 

 calculating thefe Motions, and inquiring into the Caufes of them. 

 Thofe who fuppofe that the intention of Sir Ifaac Newton, in his 

 Principioy was to inquire into tlie Caufes of the Planetary Motion, 

 appear to me to do great injuflice to Sir Ifaac, and to mlftake alto- 

 gether the nature of his work, as it is explained by himfelf in the 

 paflage above quoted*. Yet, upon this fuppofition, it is generally 

 believed, that Sir Ifaac has difcovered Attradlion to be the Caufe of 

 this Motion. This notion has produced very abfurd ways of fpeak- 

 ing. Thus, it is commonly fald that the Earth attracts the Moon, 

 and the Sun the Planets : And they tell you, that the Earth, in 

 the fame way it draws a Stone down to the ground, bends the 

 Courfe of the Moon into an Elliptical Orbit; fo that, by the fame 

 Power by which a Stone falls to the ground, the Moon is retained 

 in her Orbit - And this, they pretend. Sir Ifaac has demonftrated. 

 And we ufe the fame abfurd language when we fpeak of the Magnet 

 attracting the Iron, as if it were poffible that a Body, or any thing 

 elfe, could a£l where it was not. They tell us alfo, that it is by At- 

 traction that the Moon raifes the water of the Sea, and produces the 

 Tides ; and, in fhort, they want to make Attraction do every thing 

 in Nature, as if there were no other kind of Motion to be feen, or 

 as if Bodies going from one another (commonly called likewife by 

 an improper name, Reptilfwii, as if the one Body aCted upon the 

 other), were not as common a phaenomenon as Bodies being moved 



towards 

 * Page 412. 



