DEFINITION AND PROVINCE OP LOGIC. 13 



between musical notes, and to know the combinations of which 

 they are susceptible, but not what number of vibrations in a 

 second correspond to each ; which, though useful to be known, 

 is useful for totally different purposes. The extension of 

 Logic as a Science is determined by its necessities as an Art : 

 whatever it does not need for its practical ends, it leaves to the 

 larger science which may be said to correspond, not to any 

 particular art, but to art in general ; the science which deals 

 with the constitution of the human faculties ; and to which, in 

 the part of our mental nature which concerns Logic, as well as 

 in all other parts, it belongs to decide what are ultimate facts, 

 and what are resolvable into other facts. And I believe it will 

 be found that most of the conclusions arrived at in this work 

 have no necessary connexion with any particular views re- 

 specting the ulterior analysis. Logic is common ground on 

 which the partisans of Hartley and of Reid, of Locke and of 

 Kant, may meet and join hands. Particular and detached 

 opinions of all these thinkers will no doubt occasionally be 

 controverted, since all of them were logicians as well as meta- 

 physicians ; but the field on which their principal battles have 

 been fought, lies beyond the boundaries of our science. 



It cannot, indeed, be pretended that logical principles can 

 be altogether irrelevant to those more abstruse discussions ; 

 nor is it possible but that the view we are led to take of the 

 problem which logic proposes, must have a tendency favour- 

 able to the adoption of some one opinion, on these controverted 

 subjects, rather than another. For metaphysics, in endeavour- 

 ing to solve its own peculiar problem, must employ means, the 

 validity of which falls under the cognizance of logic. It pro- 

 ceeds, no doubt, as far as possible, merely by a closer and more 

 attentive interrogation of our consciousness, or more properly 

 speaking, of our memory ; and so far is not amenable to logic. 

 But wherever this method is insufficient to attain the end of 

 its inquiries, it must proceed, like other sciences, by means of 

 evidence. Now, the moment this science begins to draw in- 

 ferences from evidence, logic becomes the sovereign judge 

 whether its inferences are well grounded, or what other in- 

 ferences would be so. 



