24 ANTIENT METAPHYSICS. Book L 



therefore, fay, that the thing which is in generation, or in the aft of 

 being generated, is moved, but the elements of which it is compofed 

 are moved. And, as to corruption, there can be no doubt but that the 

 thing corrupted is moved ; but it is a motion which falls under one or 

 other of the four heads mentioned by Ariftotle. And, lajily, in the 

 ninth and tetith members of Plato's divifion, it is plain that he con- 

 founds the povuer moviiig, or the caufe of the motion, with the jnotion 

 itfelf. For, when one body, by impulfe upon another, moves that o- 

 ther, it is plain that the motion of the body moved is the fame as if it 

 were produced by any other caufe. And, as to the body moving, it is 

 no more than the injlrument by which the motion is performed. 

 So that body cannot, with propriety, be faid to move, but only 

 mind, either immediately and directly, or mediately by the interpofi- 

 tion of fome other body \ as, when I move a ftone by a lever, it is not 

 the lever that moves the ftone, but /ufing the lever as an inftrument. 

 And, as to the tenth, it is confounding body with mind, the motion of 

 body with the motion of mind, and the effe6i with the caufe ; for the 

 mind that moves is certainly different from body that is moved,z.wA the 

 adion of mind is likeways diftinct from the motion of body ; and the 

 motion produced in body is an effecfit which mufl be different from the 

 caufe that produces it. 



This is the divifion of Plato, liable to fo many objedlons. On the 

 other hand, Arillotle's divifion is full and comprehenfive, but without 

 repetition, or one m.ember of the divifion including the other. For 

 change of place, in the firft member, taken in a tlrid fenfe, and as it is 

 commonly underflood, for a total change of the fituation of the thing, 

 does not comprehend the other three. And it was necellary, accord- 

 ing to the notions of the antients> that thefe kinds of motions Ihould 

 be diflinguifhed from the firft : For, thougU the celcftial bodies are 

 continually changing their fituations and, in that (enfe, always in mo- 

 tion, yet, if Plato and Arifintle are iu the right, they fufFer no alte- 

 ration, augmentation, or diminution. 



The 



