520 DISSERTATION ON 



But, to come to the point : — I think it muft be admitted, that we 

 have, at lead, an idea of a circular movement, without any tendency 

 either to the center, or from it, and an idea derived from that great 

 fource, and, indeed, only fource of all our ideas concerning the opera- 

 tions of Mind, I mean confcioufnefs ; for we are fure, by our own ex- 

 perience, that, when our Mind moves our body to go round in a 

 circle, it performs that motion, w^ithout either centripetal or centri- 

 fugal inclination. It is true, that, when we perform the motion 

 quickly, and repeat it often, we have a tendency to go out of the cir- 

 cular line in the tangent ; and therefore we are obliged to incline our 

 bodies inwards towards the center. But there are two things to be 

 confidered ; firjl^ That Mind moves our body, not immediately, but 

 by the intervention of organs ; whereas, the planets being, as I obfer- 

 ved, unorganized bodies, are immediately moved by Mind. Secondly^ 

 By means of thofe organs, our bodies are moved in parts, one-half be- 

 fore the other ; whereas, we cannot conceive a fphere or fpheroid ta 

 be otherwife moved than altogether. To thefe confiderations, it may 

 be added, that the Mind which animates thofe celeflial bodies, we 

 ought to conceive as much more perfedt than our Minds, and, confe- 

 quently, that they can perform the circular motion much more regu- 

 larly than we can do ; and; in general, that all their movements are 

 infinitely more regular than ours. And, befides, we cannot conceive 

 that their Minds are {o much affected by their bodies, as ours are ; 

 for, otherwife, they would grow dizzy, and contrad a terrible vertigo^ 

 by going round always the fame way, and with fuch prodigious vdo- 

 city^ 



It is certain, therefore, that we have an Tdea of fuch a motion, and 

 that, to fuppufe the exiftence of it, implies no contradidion or inconfi- 

 ftency. It cannot, therefore, be laid down, as a felf-evident proportion, 

 which fome are much inclined to do, that every motion in a circle or 

 ellipfis, however produced, is neceffarily combined of a centripetal and a 



cea- 



