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culture whatsoever. But this natural power, even where it is strongest, may lie dead for want of the means of improvement; and a favage may have been born with as good faculties as a Bacon or a Newton. The amazing difference that appears in advanced life, is owing to this, that the talent of one was buried, being never put to ufe, while that of the other was cultivated to the best advantage.

It may likewise be observed, that the chief mean of improving our rational power, is the vigorous exercise of it, in various ways, and in different fubjects, by which the habit is acquired of exercifing it properly. Without fuch exercife, and good sense over and above, a man who has studied logic all his life may, after all, be only a petulant wrangler, without true judgement, or skill of reasoning, in any science.

I take this to be Locke's meaning, when, in his Thoughts on Education, he says, If you would have your fon to reason well, "let him read. Chillingworth." The state of things is much altered fince Locke wrote. Logic has been much improved, chiefly by his writings; and yet much lefs ftrefs is laid upon it, and lefs time confumed in it. His counfel, therefore, was judicious and feasonable; to wit, That the improvement of our reafoning power is to be expected much more from an intimate acquaintance with the authors who reafon beft, than from ftudying voluminous fystems of logic. But if he had meant, that the study of logic was of no ufe, nor deferved any attention, he furely would not have taken the pains to have made fo confiderable an addition to it, by his Effay on the Human Understanding, and by his Thoughts. on the Conduct of the Understanding. Nor would he have remitted his pupil to Chillingworth, the acutest logician, as well as the best reafoner, of his age; and one who, in innumerable places of his excellent book, without pedantry even in that pedantic age,


makes the happiest application of the rules of logic, for unraveling the fophiftical reasoning of his antagonist.

Our reafoning power makes no appearance in infancy; but as we grow up, it unfolds itself by degrees, like the bud of a tree. When a child first draws an inference, or perceives the force of an inference drawn by another person, we may call this the birth of his reafon but it is yet like a new-born babe, weak and tender; it must be cherished, and carried in arms, and have food of eafy digestion, till it gathers ftrength.

I believe no man remembers this birth of his reafon; but it is probable that his decifions will at first be weak and wavering; and, compared with that steady conviction which he acquires in ripe years, will be like the dawn of the morning compared with noon-day. We fee that the reafon of children yields to authority, as a reed to the wind; nay, that it clings to it, and leans upon it, as if conscious of its own weakness.

When reafon acquires fuch strength as to ftand on its own bottom, without the aid of authority, or even in oppofition to authority, this may be called its manly age. be called its manly age. But in most But in most men, it hardly ever arrives at this period. Many, by their fituation in life, have not the opportunity of cultivating their rational powers. Many, from the habit they have acquired, of fubmitting their opinions to the authority of others, or from fome other principle which operates more powerfully than the love of truth, suffer their judgement to be carried along, to the end of their days, either by the authority of a leader, or of a party, or of the multitude, or by their own paffions. Such perfons, however learned, however acute, may be said to be all their days children in understanding. They reason, they difpute, and perhaps write; but it is not that they may find the truth; but that they may defend opinions which have defcended to them by inheritance, or into which they have fallen by accident, or been led by affection.


I agree with Mr Locke, that there is no ftudy better fitted to exercise and strengthen the reasoning powers, than that of the mathematical sciences; for two reafons; first, Because there is no other branch of fcience which gives fuch fcope to long and accurate trains of reafoning; and, fecondly, Because in mathematics there is no room for authority, or for prejudice of any kind, which may give a false bias to the judgement.

When a youth of moderate parts begins to ftudy Euclid, every thing at firft is new to him. His apprehenfion is unsteady; his judgement is feeble; and refts partly upon the evidence of the thing, and partly upon the authority of his teacher. But every time he goes over the definitions, the axioms, the elementary propofitions, more light breaks in upon him; the language becomes familiar, and conveys clear and fteady conceptions; the judgement is confirmed; he begins to fee what demonftration is ; and it is impoffible to fee it without being charmed with it. He perceives it to be a kind of evidence which has no need of authority to strengthen it. He finds himself.emancipated from that bondage, and exults fo much in this new state of independence, that he fpurns at authority, and would have demonftration for every thing; until experience teaches him, that this is a kind of evidence which cannot be had in most things; and that in his most important concerns, he must reft contented with probability.

As he goes on in mathematics, the road of demonftration becomes finooth and eafy; he can walk in it firmly, and take wider fteps: and, at laft, he acquires the habit, not only of understanding a demonstration, but of discovering and demonstrating mathematical truths.

Thus, a man without rules of logic, may acquire the habit of reafoning justly in mathematics; and, I believe, he may, by like means, acquire the habit of reasoning juftly in mechanics, in ju


rifprudence, in politics, or in any other fcience. Good fenfe, good examples, and affiduous exercife, may bring may bring a man to reafon justly and acutely in his own profeffion, without rules. But if any man think, that from this conceffion he may infer the inutility of logic, he betrays a great want of that art by this inference for it is no better reasoning than this, That because a man may go from Edinburgh to London by the way of Paris, therefore any other road is useless.

There is perhaps no practical art which may not be acquired, in a very confiderable degree, by example and practice, without reducing it to rules. But practice, joined with rules, may carry a man on in his art farther and more quickly, than practice without rules. Every ingenious artist knows the utility of having his art reduced to rules, and by that means made a fcience. He is thereby enlightened in his practice, and works with more affurance. By rules, he fometimes corrects his own errors, and often detects the errors of others: he finds them of great ufe to confirm his judgement, to justify what is right, and to condemn what is wrong.

Is it of no use in reafoning, to be well acquainted with the various powers of the human understanding, by which we reafon? Is it of no use, to refolve the various kinds of reasoning into their fimple elements; and to discover, as far as we are able, the rules by which thofe elements are combined in judging and in reason-· ning? Is it of no use, to mark the various fallacies in reasoning, by which even the most ingenious men have been led into error? It must surely betray great want of understanding, to think thefe things ufelefs or unimportant. Thefe are the things which logicians have attempted; and which they have executed; not indeed fo completely as to leave no room for improvement, but in fuch a manner as to give very confiderable aid to our reafoning powers. That the principles laid down with regard to definition VOL. II.

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and divifion, with regard to the converfion and oppofition of propofitions and the general rules of reafoning, are not without ufe, is fufficiently apparent from the blunders committed by those who difdain any acquaintance with them.

Although the art of categorical fyllogifm is better fitted for scholaftic litigation, than for real improvement in knowledge, it is a venerable piece of antiquity, and a great effort of human genius. We admire the pyramids of Egypt, and the wall of China, tho' ufelefs burdens upon the earth. We can bear the most minute defcription of them, and travel hundreds of leagues to fee them. If any perfon fhould, with facrilegious hands, deftroy or deface them, his memory would be had in abhorrence. The predicaments and predicables, the rules of fyllogifin, and the topics, have a like title to our veneration as antiquities: they are uncommon efforts, not of human power, but of human genius; and they make a remarkable period in the progress of human reafon.

The prejudice against logic has probably been strengthened by its being taught too early in life. Boys are often taught logic as they are taught their creed, when it is an exercife of memory only, without understanding. One may as well expect to underftand grammar before he can speak, as to understand logic before he can reafon. It must even be acknowledged, that commonly we are capable of reafoning in mathematics more early than in logic. The objects prefented to the mind in this science, are of a very abstract nature, and can be distinctly conceived only when we are capable of attentive reflection upon the operations of our own understanding, and after we have been accustomed to reafon. There may be an elementary logic, level to the capacity of those who have been but little exercised in reasoning; but the most import→ ant parts of this fcience require a ripe understanding, capable of reflecting

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