CHAPTER I. 



OF INFERENCE, OB REASONING, IN GENERAL. 



1 . IN the preceding Book, we have been occupied not 

 with the nature of Proof, but with the nature of Assertion : 

 the import conveyed by a Proposition, whether that Proposi 

 tion be true or false ; not the means by which to discriminate 

 true from false Propositions. The proper subject, however, of 

 Logic is Proof. Before we could understand what Proof is, it 

 was necessary to understand what that is to which proof is 

 applicable ; what that is which can be a subject of belief or 

 disbelief, of affirmation or denial ; what, in short, the different 

 kinds of Propositions assert. 



This preliminary inquiry we have prosecuted to a definite 

 result. Assertion, in the first place, relates either to the 

 meaning of words, or to some property of the things which 

 words signify. Assertions respecting the meaning of words, 

 among which definitions are the most important, hold a place, 

 and an indispensable one, in philosophy ; but as the meaning 

 of words is essentially arbitrary, this class of assertions are 

 not susceptible of truth or falsity, nor therefore of proof or 

 disproof. Assertions respecting Things, or what may be called 

 Real Propositions, in contradistinction to verbal ones, are of 

 various sorts. We have analysed the import of each sort, and 

 have ascertained the nature of the things they relate to, and 

 the nature of what they severally assert respecting those 

 things. We found that whatever be the form of the propo 

 sition, and whatever its nominal subject or predicate, the real 

 subject of every proposition is some one or more facts or phe 

 nomena of consciousness, or some one or more of the hidden 

 causes or powers to which we ascribe those facts; and that 

 what is predicated or asserted, either in the affirmative or 



