122 REASONING. 



tion asserts, that some given subject does or does not possess some attri- 

 bute; or that some attribute is or is not (either in all or in some portion 

 of the subjects in which it is met with) conjoined with some other atti'i- 

 bute. 



We shall now for the present take our leave of this portion of our in- 

 quiry, and proceed to the peculiar problem of the Science of Logic, name- 

 ly, how the assertions, of which we have analyzed the import, are proved 

 or disproved; such of them, at least, as, not being amenable to direct con- 

 sciousness or intuition, are appropriate subjects "of j^roof. 



We say of a fact or statement, that it is pi'oved, when we believe its truth 

 by reason of some other fact or statement from which it is said io folloio. 

 Most of the propositions, whether affirmative or negative, universal, partic- 

 ular, or singular, which we believe, are not believed on their own evidence, 

 but on the ground of something previously assented to, from which they 

 are said to be inferred. To infer a proposition from a previous proposi- 

 tion or propositions; to give credence to it, or claim credence for it, as a 

 conclusion from something else ; is to reason, in the most extensive sense 

 of the term. There is a narrower sense, in which the name reasoning is 

 confined to the form of inference which is termed ratiocination, and of 

 which the syllogism is the general type. The reasons for not conforming 

 to this restricted use of the term were stated in an earlier stage of our in- 

 quiry, and additional motives will be suggested by the considerations on 

 which we are now about to enter. 



§ 2. In proceeding to take into consideration the cases in which infer- 

 ences can legitimately be drawn, we shall first mention some cases in which 

 the inference is apparent, not real ; and which require notice chiefly that 

 they may not be confounded with cases of inference properly so called. 

 This occurs when the proposition ostensibly inferred from another, appears 

 on analysis to be merely a repetition of the same, or part of the same, as- 

 sertion, which was contained in the first. All the cases mentioned in books 

 of Logic as examples of equipollency or equivalence of propositions, are 

 of this nature. Thus, if we were to argue, No man is incapable of reason, 

 for every man is rational ; or. All men are mortal, for no man is exempt 

 from death ; it would be plain that we were not proving the proposition, 

 but only appealing to another mode of wording it, which may or may not 

 be more readily comprehensible by the hearer, or better adapted to suggest 

 the real proof, but which contains in itself no shadow of proof. 



Another case is where, from a universal proposition, we affect to infer 

 another which differs from it only in being particular : as All A is B, there- 

 fore Some A is B : No A is B, therefore Some A is not B. This, too, is not 

 to conclude one proposition from another, but to repeat a second time some- 

 thing which had been asserted at first ; with the difference, that we do not 

 here repeat the whole of the previous assertion, but only an indefinite part 

 of it. 



A third case is where, the antecedent having affirmed a predicate of a 

 given subject, the consequent affirms of the same subject something already 

 connoted by the former predicate : as, Socrates is a man, therefore Socrates 

 is a living creature ; where all that is connoted by living creature Avas af- 

 firmed of Socrates when he was asserted to be a man. If the propositions 

 are negative, we must invert their order, thus : Socrates is not a living crea- 

 ture, therefore he is not a man ; for if wo deny the less, the greater, which 

 includes it, is already denied by implication. These, therefore, are not real- 



