Chap. I. ANTIENT METAPHYSICS. 325 



Tc know this belongs to the Philofophy of Mind, and to tliat Fird 

 Ph'.lofophy which diftinguilhcs accurately betwixt Body and Mind, 

 and fhows the different natures of each. Now, there are not any 

 two Sciences more different than Geometry or Mechanics, in which 

 Sir Ifaac exceeded all men, and the Philofophy of Mind, in which 

 he might have excelled too, if he had applied to it, which he had 

 not done when he wrote his Principia ; at leaft, it is not to be dif- 

 covered from that work, where there is nothing but Geometry and 

 Mechanics, Menfuration and Calculation. Nor, indeed, does he fay 

 any thing pofitively concerning the Caufe of the Planetary Motion ; 

 and it is only by inference and dcdudlion from his manner of rea- 

 foning concerning their Motion, that we fuppofe he believed their 

 Motion to be produced by Bodily Impulfe. It is only in the Scho- 

 lium Generale, quoted in the preceding note, that he gives fo much 

 as a hint that he knew any Caufe of Motion that was not mechani- 

 cal. But, in his Queries fubjoined to his Optics, he has been more 

 explicit ; and there, I think, I have fhown, and fhall further fhow 

 in the fequel, that he faid Mind was the Caufe of the Motions of the 

 Univerfe. 



From what I have faid, I think it Is evident that the Mo- 

 tions of the Celeftial Bodies are, according to Sir Ifaac's no- 

 tions when he wrote his Prmcipia, mechanical. He therefore has 

 made a Machine of our Solar Syflem ; for, whatever Motion 

 goes on of itfelf by the Power of Body merely, is, as I have 

 fhown clfewhere *, a Machine, in the proper ki\{e of the word, 

 even fuppofing, as I am perfuaded Sir Ifaac did fuppofe, that the 

 Motion proceeded originally from Mind. In order to carry on tliis 

 Mechanical Motion, he has laid it down as an axiom, that Body is 

 indifferent to a ftate of Motion or Reft, and has no natural determi- 

 nation to the one any more than to the other; fo that, being once put 

 in Motion, it continues in Motion by the fame neceflity of its na- 

 ture, 

 * See Pages 501. and 502. Vol. I. where, I think, I have explained this matter 

 diftinttly and fcientitically. 



