Chap. III. ANTIENT METAPHYSICS. 533 



That there are not too many of them, every body mufl be convin- 

 ced, who confiders what they are ; for he will find them diftind one 

 from another, and that not one includes another. Nor do I think 

 that any philofopher has thought that the number of them was too 

 great. But it appears, from Simplicius's commentary upon the cate- 

 tegories of Ariftotle, that many of the commentators before hini^ 

 thought them too few, and therefore were inclined to add to the num- 

 ber, and, particularly, to make motion one of them. 



I will therefore begin with motion, and endeavour to account why 

 it is not one of the univerfals of Archytas : And I hope this will not 

 be difficult to do, after what 1 have faid of it ; for, in xh^frji place, it 

 is evidently not one of Khtfonnai caufes of natural things, of which, 

 as I have oblerved, Archytas treats in this work, but one of the effi- 

 cient caufes, and, indeed, the immediate efficient caufe of all genera- 

 tion and produdion ; it cannot, therefore, be faid to be any thing ex- 

 iting that is generated and produced, but the caufe of fuch exiltence. 

 2<i/j, It is not only not any thing, but it can nut be faid to be ^.Wcjlate 

 of any thing ; for it is, as we have {Q<in^ a paflfage from one ftate to a- 

 nother. As, however, it cannot be denied that it afFcds natural things 

 very much, and produces great changes and alteradons upou ihem, 

 the efFeds of motion, if not moiion itieif, muit De conlidered as lailing. 

 under the catcgones of doing .m\(\ Juff cringe the moving power being 

 confidered as doing and aciing ; and the thing moved^ -d.^ juffei ing. 



Akin to motion h time ; which, as fhall be fhown afterwards, is- 

 nothing elfe but number applied to motion, by which the duration of 

 the exiftence of any thing is meafured. This, confidered anfluteiy 

 and abftradedly in itfelf, is certamly no natural thing exiiling, and, 

 therefore, does not belong to rchytas'b lubjed: ; but, as it acco:n})a- 

 nies the exigence of material things *, I propofe to treat or it, ucder 



the 



* This is the reafon given by '-Implicius, why neither time nor place are rxkor-ed 

 among the categories ^ becaufe, fays he, they are ibmething without nature, thac is, 



not. 



