Chap. IV. ANTIENT METAPHYSICS. 401 



this is what is called demonjlration. And a fyllogifm of this kind is 

 a demonftrative fyllogifm ; the nature of which, as diftinguifhed from 

 other fyllogifms, is explained by Ariftotle in his laft Analytics, or Fof- 

 teriora^ as they are commonly called by the Latin interpreters. 



And here the reader may obferve the general method of this great 

 work of Analyfis ; the defign of which, as Ariftotle tells us in the 

 beginning of it, was to fhow what fcience or demonftration is ; a 

 queftion very much agitated in the Theaetetus of Plato, but nothing 

 determined. And I have little doubt but that Ariftotle defired to have 

 the glory of anfwering a queftion which his mafter had only puzzled 

 and perplexed. Now, analyfis is the method of invention in every 

 fcience; for, in difcovering any fcience, we begin with the compound, 

 and relolve it into its elements or firft principles ; but, according 

 to the method of teaching, where the analyfis ends, there the 

 teaching begins. Thus, whoever firft made a fcience of language, 

 muft have begun with the compound^^^c:^, which he would conti- 

 nue to analyfe or unravel, till he came to its ultimate elements, viz. 

 the elemental or uncompounded founds ; and, where the analyfis 

 ends, the grammatical art, as it is taught, begins*. 



In the fame manner, Ariftotle, propofing to explain the de- 

 monftrative fyllogifm, analyfes it firft into the fyllogifm of which 



E e e it 



• It is the fame in praSIice as in thory. When any thing is propofed to be done, 

 the mind begins with the contemplation of that thing; and then it confiders all the 

 particulars which are neceflary for the doing it. And in doing this, it goes back in 

 order, till it comes to what is firft to be done. Thus, if a man propofes to build a 

 , houfe, the completion of which is the putting on the roof, by which it is to anfwer the 

 chief purpofe of a houfe; the beginning of the theory is the roof or covering ; but, in 

 order to fupport a roof, there muft be walls ; and, in order to have walls, a foundation 

 muft be dug. And here, where the theory ends, the pradlice begins. 



