Sect. IV.

The superiority of scientific evidence re-examined.

the truth of the propositions therein demonstrated. Is he in the smallest degree surer of any of the properties of the circle, than that if he take away his hand from the compasses, with which he is describing it on the wall, they will immediately fall to the ground, These things affect his mind, and influence his practice, precisely in the same manner.

So much for the various kinds of evidence, whether intuitive or deductive; intuitive evidence, as divided into that of pure intellection, of consciousness, and of common sense, under the last of which that of memory is included; deductive evidence, as divided into scientific and moral, with the subdivisions of the latter into experience, analogy, and testimony, to which hath been added, the consideration of a mixed species concerning chances. So much for the various subjects of discourse, and the sorts of eviction of which they are respectively susceptible. This, though peculiarly the logician's province, is the foundation of all conviction, and consequently of persuasion too. To attain either of these ends, the speaker must always assume the character of the close and candid reasoner; for, though he may be an acute logician who is no orator, he will never be a consummate ora tor who is no logician.

CHAP. VI.

Of the nature and use of the scolastic art of Syllogising.

HAVING, in the preceding chapter, endeavoured to trace the outlines of natural logic, perhaps with more minuteness than in such an enquiry as this was strictly necessary, it might appear strange to pass over in silence the dialectic of the schools; an art which, though now fallen into disrepute, maintained, for a tract of ages, the highest reputation among the learned. What was so long regarded, as teaching the only legitimate use and application of our rational powers in the acquisition of knowledge, ought not surely," when we are employed in investigating the nature and the different sorts of evidence, to be altogether overlooked.

Ir is long since I was first convinced, by what Mr Locke hath said on the subject, that the syllogistic art, with its figures and moods, serves more to display the ingenuity of the inventor, and to exercise the address and fluency of the learner, that to assist the diligent inquirer in his researches after truth. The method of proving by syllogism, appears, even on a superficial review, both unnatural and prolix. The rules laid down for distinguishing the conclusive from the incon

Of the nature and use of the scholastic art of syllogizing.

clusive forms of argument, the true syllogism from the various kinds of sophism, are at once cumbersome to the memory, and unnecessary in practice. No person, one may venture to pronounce, will ever be made a reasoner, who stands in need of them. In a word, the whole bears the manifest indications of an artificial and ostentatious parade of learning, calculated for giving the appearance of great profundity, to what in fact is very shallow. Such, I acknowledge, have been, of a long time, my sentiments on the subject. On a nearer inspection, I cannot say I have found reason to alter them, though I think I have seen a little furtherinto the nature of this disputative science, and consequently into the grounds of its futility. I shall, therefore, as briefly as possible, lay before the reader a few observations on the subject, and so dismiss this article.

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PERMIT me only to premise, in general, that I proceed all along on the supposition, that the reader hath some previous acquaintance with school-logic. It would be extremely superfluous, in a work like this, to give even the shortest abridgment that could be made of an art so well known, and which is still to be found in many thousand volumes. On the other hand, it is not necessary that he bé an adept in it, a mere smattering will sufficiently serve the present purpose.

My first observation is, that this method of arguing has not the least affinity to moral reasoning, the procedure in the one being the very reverse of that employed in the other. In moral reasoning we proceed

Of the nature and use of the scholastic art of syllogizing.

by analysis, and ascend from particulars to universals; in syllogizing we proceed by synthesis, and descend from universals to particulars. The analytic is the only method which we can follow, in the acquisition of natural knowledge, or of whatever regards actual existences; the synthetic is more properly the method that ought to be pursued in the application of knowledge already.acquired. It is for this reason it has been called the didactic method, as being the shortest way of communicating the principles of a science. But, even in teaching, as often as we attempt, not barely to inform, but to convince, there is a necessity of recurring to the tract in which the knowledge we would convey was first attained. Now, the method of reasoning by syllogism, more resembles mathematical demonstration, wherein, from universal principles, called axioms, we deduce many truths, which, though general in their nature, may, when compared with those first principles, be justly stiled particular. Whereas, in all kinds of knowledge, wherein experience is our only guide, we can proceed to general truths, solely by an induction of particulars.

AGREEABLY to this remark, if a syllogism be regular in mood and figure, and if the premises be true, the conclusion is infallible. The whole foundation of the syllogistic art lies in these two axioms: " Things "which coincide with the same thing, coineide with "one another;" and, "Two things, whereof one does, "and one does not coincide with the same thing, do "not coincide with one another." On the former rest

Of the nature and use of the scholastic art of syllogizing.

all the affirmative syllogisms, on the latter all the negative. Accordingly, there is no more mention here of probability and of degrees of evidence, than in the operations of geometry and algebra. It is true, indeed, that the term probable may be admitted into a syllogism, and make an essential part of the conclu sion, and so it may also in an arithmetical computa tion; but this does not in the least affect what was advanced just now; for, in all such cases, the proba bility itself is assumed in one of the premises: whereas, in the inductive method of reasoning, it often hapthat from certain facts we can deduce only pro pens, bable consequences. bra two d zoned. jas vi

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I OBSERVE, Secondly, that though this manner of ar guing has more of the nature of scientific reasoning, than of moral, it has, nevertheless, not been thought worthy of being adopted by mathematicians, as a proper method of demonstrating their theorems. I am satisfied that mathematical demonstration is capable of being moulded into the syllogistic form, having made the trial with success on some propositions. But that this form is a very incommodious one, and has many disadvantages, but not one advantage of that commonly practised, will be manifest to every one who makes the experiment. It is at once more indirect, more tedious, and more obscure. I may add, that if into those abstract sciences one were to introduce some specious fallacies, such fallacies could be much more. easily sheltered under the awkward verbosity of this