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knowledge, therefore, the syllogism is, if possible, still more defective than as a mode of acquiring it. It does not give any additional knowledge, nor communicate the knowledge which it does communicate in any simpler, or shorter, or surer way. On the contrary, whatever knowledge it gives, it renders more confused by being more cumbrous; and it cannot fail to train the mind, which receives instructions in this way, to two of the most dangerous practical errors,—the errors of admitting, without proof, only what requires proof, and of doubting, that is to say, of requiring proof, only of what is evident. Such is the syllogism, considered as an instrument, either for forwarding our own attainments in knowledge, or for communicating these attainments to others.
The triumph of the syllogistic art, it must be confessed, however, is not as an art of acquiring or communicating truth, but as an art of disputation as the great art of proving anything by anything, quidlibet per quodlibet probandi. And, if it be a merit to be able to dispute long and equally well, on subjects known and unknown, to vanquish an opponent, by being in the wrong, and sometimes too by being in the right, but without the slightest regard either to the right or wrong, and merely as these accidental circumstances may have corresponded with certain skilful uses of terms without a meaning,--this merit the logicians of the schools unquestionably might claim. Indeed in controversies of this sort, in those ages of endles controversy,“ success,” as it has been very truly remarked, “ tended no more to decide the question, than a man's killing his antagonist in a duel serves now to satisfy any person of sense that the victor had right on his side, and that the vanquished was in the wrong."
Of this system of logic, the views given by philosophers, during the period in which it flourished, are almost innumerable ; and, in no other works can we find so striking a mixture of intellectual strength and intellectual weakness, of acuteness, capable of making the nicest and most subtile distinctions, with an imbecility of judgment, incapable of estimating the insignificance of any one of those subjects, on which so many nice and subtile distinctions were made. All these commentaries, and systematic views, however,though all that is valuable in them were condensed into a few pages-would scarcely be equal in value to the few pages of a commentary of a different kind; in which the maxims of logic are
adapted with most singular happiness, to a ludicrous theory of syllogism, the striking coincidences of which, with the actual laws of the syllogism, will be best felt by those to whom the rules of syllogizing are most familiar.
“ Though I'm afraid I have transgressed upon my reader's patience already, I cannot help taking notice of one thing more extraordinary than any yet mentioned; which was Crambe's Treatise of Syllogisms. He supposed that a philosopher's brain was like a great forest, where ideas ranged like animals of several kinds ; that those ideas copulated, and engendered conclusions; that when those of different species copulate, they bring forth monsters or absurdities; that the major is the male, the minor the female, which copulate by the middle term, and engender the conclusion. Hence they are called the præmissa, or predecessors of the conclusion ; and it is properly said by the logicians quod pariant scientiam, opinionem, they beget science, opinion, &c. Universal propositions are persons of quality ; and therefore in logic they are said to be of the first figure. Singular propositions are private persons, and therefore placed in the third or last figure, or rank. From those principles all the rules of syllogisms naturally follow.
“1. That there are only three terms, neither more nor less ; for to a child there can be only one father and one mother.
6 II. From universal premises there follows an universal Codclusion, as if one should say, that persons of quality always beget persons of quality.
“ III. From singular premises follows only a singular conclusion, that is, if the parents be only private people, the issue must be so likewise.
“IV. From particular propositions nothing can be concluded, because the individua vaga are (like whoremasters and common strumpets) barren.
V. There cannot be more in the conclusion than was in the premises, that is, children can only inherit from their parents.
“ VI. The conclusion follows the weaker part, that is, children inherit the diseases of their parents.
" VII. From two negatives nothing can be concluded, for from divorce or separation there can come no issue.
“VIII. The medium cannot enter the conclusion, that being logical incest.
“IX. An hypothetical proposition is only a contract, or a promise of marriage ; from such, therefore, there can spring no real issue.
“X. When the premises, or parents, are necessarily joined, (or in lawful wedlock) they beget lawful issue ; but contingently joined, they beget bastards.
“ So much for the affirmative propositions ; the negative must be deferred to another occasion.
“ Crambe used to value himself upon this system from whence he said one might see the propriety of the expression, such a one has a barren imagination; and how common is it for such people to adopt conclusions that are not the issue of their premises; therefore as an absurdity is a monster, a falsity is a bastard; and a true conclusion that followeth not from the premises, may properly be said to be adopted. But then what is an enthymeme? (quoth Cornelius.) Why, an enthymeme (replied Crambe,) is when the major is indeed married to the minor, but the marriage kept secret."*
Of the direct influence of the school logic, in retarding, and almost wholly preventing the progress of every better science, I need not attempt any additional illustration, after the remarks already offered. But the indirect influences of this art were not less hurtful.
One of the most hurtful consequences of this method, was the ready disguise of venerable ratiocination which it afforded for any absurdity. However futile an explanation might be, it was still possible to advance it in all the customary solemnities of mood and figure; and it was very natural, therefore, for those who heard what they had been accustomed to regard as reasoning, to believe, that, in bearing a reasoning, they had heard a reason. Of this 1 may take an instance which Lord Kames has quoted from the great inventer of the system bimself, and one which very few of his followers have been able to surpass. “ Aristotle, who wrote a book about mechanics, was much puzzled about the equilibrium of a balance, when unequal weights are hung upon it, at different distances from the centre. Having observed that the arms of the
Memoirs of Martinus Scriblerus, B. i. c. 8.
balance describe portions of a circle, he accounted for the equi-
of this technical system, I may remark, that the constant necessity of having recourse to some syllogistic form of argument, and of using these forms, in cases in which the opinions, involved in the syllogism, were at least as clear before the syllogism as after it, rendered argument and belief, by a sort of indissoluble association almost synonymous terms. If we had still to prove John to be fallible, after having proved or at least obtained assent to the proposition, that all men are fallible, it was not easy to discover any truth, so self-evident, as not to stand at least equally in need of demonstration. Hence the constant tendency in the scholastic ages to prove what did not stand in need of proof. Everything was to be demonstrated, and everything was demonstrated; though it must be confessed, that the only effect of the demonstration frequently was to render obscure -at least as obscure as anything self-evident could be rendered what, but for the demonstration, could not have admitted of the slightest doubt.
Akin to this tendency of proving every thing-even self-evident propositions—by some syllogistic form, was the tendency which the mind acquired, to apply many varieties of technical phraseology to the same proposition, so as to make many propositions of one, as if every repetition of it, in another form of language, were the enunciation of another truth. It is impossible to take up a volume of any of the old logicians, and to read a single page of it, without discovering innumerable examples of the influence of which I speak. Indeed, as the forms of technical expression, or at least the possible combinations of these, are almost in
Sketches of the History of Man, B. iii. Sk. i. 2.
finite, it is, in many cases difficult to discover what principle of forbearance and mercy to the reader, led the logician to stop at one of his identical propositions, rather than to extend the supposed ratiocination through many similar pages. There can be no doubt, at least, that the principle which produced many pages, might, with as much reason, have produced a whole volume.
It is not easy to imagine a proposition that would less stand in need of proof, than that which affirms what is possible and what is impossible, not to be the same; or if, for the honour of logic, that nothing might be allowed to be credited without mood and figure, a syllogism should be thought necessary, a single syllogism seems all that could, with any decency, be claimed. But how many syllogisms does an expert logician employ to remove all doubt from this hardy proposition! The example which I take, is not from those darker ages, in which almost any absurdity may readily be supposed, but from the period which produced the Essay on the Human Understanding. It is from a work of a logician, David Dirodon, a professor in one of the French universities-an author, of no ordinary merit, who in many cases reasons with singular acuteness, and whose works were held in such high admiration, that he was requested, by a provincial synod of the church, to make as much haste as possible, to publish his course of philosophy for the benefit of the churches, tanquam ecclesiis nostris pernecessarium. The argument which I quote from him, may be considered therefore, not as an instance of logical pleonasm peculiar to him, but as a very fair example of the technical argumentation of the period.
His demonstration, that things possible and things impossible, are not the same, is contained in six weighty paragraphs, of which I translate literally, the first two, that are sufficiently absurd indeed, but not more absurd than the paragraphs which follow them.
“Whatever, of itself and in itself, includes things contradictory, differs in itself, from that which, of itself and in itself, does not imply any thing contradictory. But what is impossible of itself and in itself, involves things contradictory,--for example, an irrational human being, a round square. But what is possible of itself and in itself, includes no contradiction. Therefore, what is impossible in itself, differs from what is possible.