4 INTRODUCTION. 



definition. It involves, at all events, no arbitrary 

 change in the meaning of the word ; for, with the 

 general usage of the English language, the wider sig- 

 nification, I believe, accords better than the more 

 restricted one. 



$ 3. But reasoning, even in the widest sense of 

 which the word is susceptible, does not seem to include 

 all that is included, either in the best, or even in the 

 most current, conception of the scope and province 

 of our science. The Employment of the word Logic 

 to denote the theory of argumentation, is derived from 

 the Aristotelian, or, as they are commonly termed, the 

 scholastic logicians. Yet even with them, in their 

 systematic treatises, argumentation was the subject 

 only of the third part: the two former treated of 

 terms, and of propositions ; under one or other of 

 which heads were, moreover, included, Definition and 

 Division. Professedly, indeed, these previous topics 

 were introduced only on account of their connexion 

 with reasoning, and as a preparation for the doctrine 

 and rules of the syllogism. Yet they were treated 

 with greater minuteness, and dwelt upon at greater 

 length, than was required for that purpose alone. 

 More recent writers on logic have generally under- 

 stood the term as it was employed by the able authors 

 of the Port Royal Logic; viz., as equivalent to the 

 Art of Thinking. Nor is this acceptation confined 

 to philosophers, and works of science. Even in con- 

 versation, the ideas usually connected with the word 

 Logic, include at least precision of language, and accu- 

 racy of classification : and we perhaps oftener hear 

 persons speak of a logical arrangement, or expressions 

 logically defined, than of conclusions logically deduced 

 from premisses. Moreover, a man is often called a 



