3i8 ANTIENT METAPHYSICS. Book V. 



try and Numbers to the Motions of Bodies, p.nd mcafure and com- 

 pute ever lb well, yet, if we do not know the Caufcs of thefe Mo- 

 tions, we are not Fhilofopbcrs. 



Neither fhould we confound, as many do, the generalizing of any 

 Eircvfl with the knowledge of itsCaufe. Though I know that a (lone 

 falls to the ground, not only here, but every where in Europe, Afia, 

 and America, yet I am not more learned as to the caufe of it, than it 

 I knew that it happened only in one fingleinftance : And, in general, 

 we muft diftinguilh betwixt Natural Hiftory and Philofophy ; for, 

 though we know ever fo many fads of Natural Hiflory, and their 

 feveral connexions and relations to one another, yet, if we do not 

 know their Caufes, we are not philofophers. 



Unlefs, therefore, the admirers of Sir Ifaac Newton will maintain 

 that he was as great aPhilofopher as he was an Aftronomer, Geometer, 

 Scientifical Mechanic, and accurate obferver of the Phaenomena of 

 Nature, and particularly that he excelled in Metaphyftcs and the 

 Firjl Philofophy^ which inveftigates the Firjl Caufes and Principles 

 of things, they ought not to be alarmed at what I have faid in the 

 Firft Volume, and fhall further fay in this, upon the fubjed of his 

 Prhicipia ; nor think that it is an attack that I make upon his Syflem 

 of Aflronomy ; for it is only concerning the beginning and continuance 

 of Motion, with which Sir Ifaac fets out in that work, that I find 

 fault. Now, he may be in an error as to the Cauje of the Motion of 

 the Planets, and yet be perfedly right as to the Laivs of that Mo- 

 tion, and may have calculated and meafured it with the greateft de- 

 gree of exadtnefs. And the candid reader will the more readily ex- 

 cufe me, that, in my apprehenfion, Sir Ifaac was under no neceflity 

 at all to fay any thing of the Caufe of the Motion of theCeleftial Bo- 

 dies, which, as I have faid, belongs to a Science quite different from 

 Aftronomy. If, therefore, he has gone out of his province as an 

 Aftronomer, and intrenched upon that of the philofopher, and at 



the 



