AND ON LOGIC IN GENERAL. 



189 



logical and metaphysical whole, or whether those who do it imagine themselves in accordance 

 with the old writers, is a point which I have not seen settled, nor even alluded to, by those to 

 whom alone belongs the power of deciding it. Except so far as this. The preceding table 

 of descent, from the summum genus to the individuals, was partly written in answer to pas- 

 sages of my second paper in which the view of the Port Royal logic was taken ; that is, 

 the affirmative proposition was made intensively universal in the predicate, the negative pro- 

 position intensively particular. I and some others were declared to be wrong : but whether 

 the Port Royal authors were among those others was not stated, though I suspect that my 

 reviewer mentioned in the previous note is included. 



Of course no one can object to the truth of the proposition that some individual instances 

 of the quality animal are distributed, one a piece, among all men. This proposition can be 

 thought, and is thought ; and it is not quite the same thought as ' All men are so many 

 animals.' But this very subordinate distinction is not the one which Aristotle laid down, and 

 which he obtained from the necessities of human thought. He meant that animal contains 

 man, foe animal is aggregate of man and brute : but (aXXoxr) man contains animal, for man is 

 compound of animal and reason. 



IX. The quantification of the predicate has been the guide under which the school against 

 which I contend has been led to take a reduplication of the mathematical side of logic for an 

 introduction of the metaphysical side. This quantification they justify by the postulate that 

 logic ought to be allowed to find language for all that is contained in thought. Whether 

 usual thought does quantify the predicate may be doubted : but this does not matter ; for 

 the postulate should have had can be instead of is. It is the business of logic, as a mental* 

 gymnastic, to put into activity all the powers, if any, which ordinary life allows to lie dormant. 

 Of every mode of thinking, as of every mode of using the muscles, it is certain that it was 

 meant for a purpose, and for a purpose which cannot be so well accomplished without it. 

 Accordingly, the syllogism of the predicate quantified by postulation has its proper place : 

 I believe that place to be, as I shall point out, in company with the common form of syllogism, 

 and the numerically definite syllogism, in the arithmetical whole, or whole of first intention. 



But there is one mode of thought, very often expressed in common life, and almost always 

 implied, which logic has wilfully neglected, to the serious curtailment of her field of operation. 

 Her pictures are not bounded by a frame, with landscape and sky definitely painted up to the 

 sides of the rectangle ; but have only a foreground with an indefinite back shading, equally 

 signifying, under the type of an exclusion, the distant hill and the intermediate river. The 

 contrary of the name or term, the not-X of the X, is made only aorist, indefinite, standing 

 for more or less, no matter which, of the whole universe of thought. But not only is common 



• A learned writer denies it this character, in its primary 

 purpose. He says that logic is no more designed primarily to 

 give men facility in the practice of reasoning than a treatise 

 on optics is intended to improve their sight. The parallel is 

 imperfect. Suppose that optics neither liad, nor could have, 

 other subject-matter than spectacles; that men did nothing in 

 their waking moments without making spectacles ; that religion 

 and morals, life and manners, food and clothing, &c. &c. all 

 depended in the highest degree upon every man, or most men, 



making those spectacles well which they must all make well 

 or ill. In such a case ' Optics, or the art of improving defective 

 vision ' would be no very absurd title : nor, as man is consti- 

 tuted, is there any great objection to 'Logic, or the art of 

 reasoning.' It would be better to say ' Optics, or the form of 

 spectacle-making, with a view to the improvement of vision ' 

 and ' Logic, or the form of thought,with a view to the im- 

 provement of reason.' 



