Chap. III. ANTIENT METAPHYSICS. 19 



and, from this double connexion, Arlftotle has given us two defini- 

 tions of it, one of them taken from the energy, or end, to which it 

 tends, the other from the capacity from which it begins. The firft 

 is exprelTed in two words, 'uiz. tvtpyux xtim^ *j or imperfed energy ; the 

 other is £»t£Xs^«« Te» sv l-jmu.e< \ tv ^«v«^«, which may be tranflated thus : 



* The ferfe6iion of ivhat is in capacity , confidered merely as in capaei- 



* //.* The meaning of the laft words is, that nothing is confidered 

 in the thing that is moved, but merely its capacity : So that motion 

 is the perfection of that capacity, but not of the thing itfelff- Ihe 

 reafon why it is faid to be the perfection of capacity is,thatitis forae- 

 thing more than mere capacity ; for it is capacity exerted, which, 

 when it has attained its end, fo that the thing has arrived at that ftate 

 to which it is deftined by nature, or art, ceafes, and the thing 

 begins to exlft sysgy««£, or acliially : And, therefore, Ariftotle has very 

 properly called this exertion the perfe^lion of capacity^ fince capacity 

 can go no further. 



This laft definition appears to be that which Ariftotle prefers ; for 

 he has given us the other only as it were in pafling ; v^rbereas this he 

 has given us, when treating formally of the fubjeCt ; and no doubt it 

 is a better definition ; for rhe other is a definition by negation ; 

 whereas this tells us pofitively what the thing is, and makes the pro- 

 per difiinclion betwixt mcvt capacity i 2in(\ capacity exerted ; and alio 

 betwixt the utmoft perfedion of capacity^ and energy^ or the thing 

 compleated. 



In this manner I have explained, at fome length, this famous de- 

 finition of Ariftotle, which by many has been complained of as ob- 



fcure ; 



* Ariftotle, 5r£g< •v^^Piivjj, lib. 2 cap 5. 



t In this wr.y Ariftotle hi;..l"t'lf has explained thefe words in the ytli chap, of his 

 Jjth book of Mctaphyfics. A piece oi bi ^s, fays he, is a itc!tUL", hurxfcn (01 in capa' 

 city) \ but the motion by which it becomes a ftatue is not ttTtxt^^fiK, or xhc J/cr/cCl ion of 

 the brafs, but the perfection of its capacity. 



