20 NAMES AND PROPOSITIONS. 



subject of logic, is an operation which usually takes 

 place by means of words, and in all complicated cases 

 can take place in no other way ; those who have not 

 a thorough insight into the signification and purposes 

 of words, will be under almost a necessity of reasoning 

 or inferring incorrectly. And logicians have generally 

 felt that unless, in the very first stage, they removed 

 this fertile source of error ; unless they taught their 

 pupil to put away the glasses which distort the object, 

 and to use those which are adapted to his purpose in 

 such a manner as to assist, not perplex, his vision ; he 

 would not be in a condition to practise the remaining 

 part of their discipline with any prospect of advantage. 

 Therefore it is that an inquiry into language, so far 

 as is needful to guard against the errors to which it 

 gives rise, has at all times been deemed a necessary 

 preliminary to the science of logic. 



But there is another reason, of a still more funda- 

 mental nature, why the import of words should be 

 the earliest subject of the logician's consideration : 

 because without it he cannot examine into the import 

 of Propositions. Now this is a subject which stands 

 on the very threshold of the science of logic. 



The object of logic, as defined in the Introductory 

 Chapter, is to ascertain how we come by that portion 

 of our knowledge (much the greatest portion) which 

 is not intuitive; and by what criterion we can, in 

 matters not self-evident, distinguish between things 

 proved and things not proved, between what is 

 worthy and what is unworthy of belief. Of the 

 various questions which the universe presents to our 

 inquiring faculties, some are soluble by direct con- 

 sciousness, others only by means of evidence. Logic 

 is concerned with these last. The solution, by means 

 of evidence, of questions respecting the universe and 



