:isS ANTIENT METAPHYSICS. Book V. 



' allow ihis : I believe they are milled, as I myfelf have formerly 



* been mifled, by the expreffion, a State of Motion. Motion is a 

 ' Change ; a Continuation of Motion is a further Change ; a fur- 

 ' ther Change is a Repeated Effed: ; a Repeated Effedl requires a 

 ' Repeating Caufe. State implies the contrary of Change ; and 



* Motion being Change, a State of Motion is a contradidion in 



' terms.' 



The lafl authority I fhall mention is that of Sir Ifaac himfelf, in 

 the Queries fiibjoined to his Optics, where he has faid, in fo many 

 words, That there are certain adive principles, by which the par- 

 ticles of Matter are moved, and which are the caufes of Gravitation, 

 Magnetic and Eledric Attradions, of Fermentation, and the Cohe- 

 fion of Bodies ; and he further fays, that, by the Vis Tnertiae alone, 

 which is a mere paflive principle, it is impoffible to account either 

 for the beginning or the continuation of Motion *. Now, if the 



• ■ Vis 



on; 



* I have given Sir Ifaac's words, Vol. I. page 547. And I will here fubjoin ano- 

 ther palTage from the fame work, viz his Qiieries, annexed to the fecond edition 

 of his Optics, page 376. ; where, after having enabliflied that all Bodies are compo- 

 fed of Primitive Particles, as he calls them, infinitely harder than any Bodies com- 

 pofcJ of them, fo very hard, as never to wear or break to pieces, by the means of 

 which /ifrman^'n/ particles, Nature, he fays, is prefervcd, and lalls foiever, amidft 

 all the various changes of corporeal things, he adds, ' It feems to me farther, that- 

 ' thefe Particles have iror only a Vi^ Inertiae, accompanied with fuch paffive laws 

 • ! of Motion as naturally refult from thai force, but alfo, that they are moved by 

 .''certain a£live Principles, fuch as is that of Gravity, and that which caufes Fcr- 

 ' mentation, and the Cohefion of Bodies.' Now, I would defvre to know what 

 thefe JElive Principles are, by which the Particles of Matter are moved, and by 

 which, as Sir Ifaac fays, Gravity, Fermentation, and the Cohefion of Bodies, are 

 produced ? They are certainly different from the Particles tbemfclves, in which 

 they are inherent. And it is evident, not only fiom this paffagc, and from the o- 

 iher paiTage I baye quoted in the Fiift Volume, but from every thing that Sir Ifaac 



has 



