5l6 DISSERTATION ON 



I think, is hardly to be conceived, far lefs to be denionftrated ; for 

 to me, who am not learned in the fublime geometry, and in the doc- 

 trine of prime and ultimate ratios, it does not appear pofTible that any 

 part of the circular motion, not even the leaft part, can be in a ftraight 

 line ; and, therefore, I cannot conceive how the motion fhould be- 

 gin in a flraight line, which, however, is Sir Ifaac's fuppofition. 

 And I think it is very near as difficult to conceive how the fame 

 Mind fhould firft move the body towards the center, and then impell 

 it in a ftraight line from the center, though, if that were the cafe, there 

 would be no part of the orbit in a ftraight line. If, indeed, the motion 

 were produced by different powers, this, as I have faid, would be 

 neceflary. But it is hardly conceivable how one and the fame mo- 

 ving power fhould, in the fame motion, and at the very fame inftant, 

 aCt and counteraft itfelf. But further — Suppofing the poffibility were 

 admitted of IViind producing a circular motion in this indirect and 

 round about way, either by firft projeding it, or firft moving it to- 

 wards the center, I think it cannot be denied but that, at leaft, it is 

 pofTible that Mind may give a circular motion to body in the fimple 

 and dired manner, as we know, from certain experience, that our 

 Mind can move our Body in a circle, without beginning, either by a 

 motion in a ftraight line, or by a motion towards the center ; and, if 

 it be poffible to be done in that plain and fimple way, we muft pre- 

 fume that, as Supreme Intelligence prefides in the univerfe, it is 

 done in no other way. 



But, pioy If it be true what I have laid down, fupported by the au- 

 thority of Dodor Clarke, that it is impoffible, by the nature of things, 

 that Mind can move body, as body moves body, that is, by impulfe, 

 there 16 an end of Sir llaac's fyftem, fo far as it is founded upon 

 the i-iojedile motion ; for that motion can be underftood to be no- 

 thiri; elfe but an impulfe by which the body is moved in a ftraight 

 line •, and fo, I believe, it is underftood by all the Newtonians. Now, 

 if it be true, that it is impoffible that Mind can adl upon body in the 



way 



