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count of his own judgement and learning, thinks that the doctrine of modals ought to be banished out of logic, and remitted to grammar; and that if the grammar of the Greek tongue had been brought to a fyftem in the time of Ariftotle, that most acute philofopher would have faved the great labour he has beftowed on this fubject.

Burgerfdick, after enumerating five claffes of modal fyllogifms, obferves, that they require many rules and cautions, which Aristotle hath handled diligently; but that as the ufe of them is not great and their rules difficult, he thinks it not worth while to enter into the difcuffion of them; recommending to thofe who would understand them, the most learned paraphrafe of Joannes Monlorius upon the first book of the First Analytics.

All the writers of logic for two hundred years back that have fallen into my hands, have paffed over the rules of modal fyllogiíms with as little ceremony. So that this great branch of the doctrine of fyllogifm, fo diligently handled by Ariftotle, fall into neglect, if not contempt, even while the doctrine of pure fyllogifms con

tinued in the highest efteem. Moved by thefe authorities, I fhall let this doctrine rest in peace, without giving the least difturbance to its aíhes.

SECT. 7. On Syllogifms that do not belong to Figure and Mode.

Ariftotle gives fome obfervations upon imperfect fyllogifms: fuch as, the Enthimema, in which one of the premises is not expreffed but understood: Induction, wherein we collect an univerfal from a full enumeration of particulars: and Examples, which are an imperfect induction, The logicians have copied Ariftotle upon these kinds of reafoning, without any confiderable improvement. But to compensate the modal fyllogifms, which they have laid afide, they have given rules for feveral kinds of fyllogifm, of which Ariftotle takes no notice. These may be

reduced to two claffes.

The first clafs comprehends the fyllo gifms into which any exclufive, restrictive, exceptive, or reduplicative propofition enters. Such propofitions are by fome called 3C2 exponible,

exponible, by others imperfectly modal. The rules given with regard to these are obvious, from a juft interpretation of the pofitions.

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The fecond clafs is that of hypothetical fyllogifins, which take that denomination from having a hypothetical propofition for one or both premifes. Moft logicians give the name of hypothetical to all complex propofitions which have more terms than one fubject, and one predicate. I ufe the word in this large fenfe; and mean by hypothetical fyllogifms, all thofe in which either of the premises confifts of more terms than two. How many various kinds there may be of fuch fyllogifms, has never been afcertained. The logicians have given names to fome; fuch as, the copulative, the conditional by fome called hypothetical, and the disjunctive.

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Such fyllogifms cannot be tried by the rules of figure and mode. Every kind would require rules peculiar to itself. Logicians have given rules for fome kinds; but there are many that have not fo much

as a name.

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The Dilemma is confidered by most logicians as a fpecies of the disjunctive fyllogifm.

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logifm. A remarkable property of this kind is, that it may fometimes be happily retorted it is, it feems, like a hand-grenade, which by dextrous management be thrown back, fo as to fpend its force upon the affailant. We fhall conclude this tedious account of fyllogifms, with a dilemma mentioned by A. Gellius, and from him by many logicians, as infoluble in any other way.

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Euathlus, a rich young man, defirous "of learning the art of pleading, applied

to Protagoras, a celebrated fophift, to "inftruct him, promifing a great fum of

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money as his reward; one half of which 66 was paid down; the other half he

bound himself to pay as foon as he "fhould plead a caufe before the judges, "and gain it. Protagoras found him a

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very apt fcholar; but, after he had "made good progress, he was in no haste "to plead causes. The master, concei"ving that he intended by this means to "fhift off his fecond payment, took, as "he thought, a fure method to get the "better of his delay. He fued Euathlus "before the judges; and, having opened "his caufe at the bar, he pleaded to this purpose.

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" purpose. O most foolish young man, "do you not fee, that, in any event, I "must gain my point? for if the judges give fentence for me, you must pay

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by their fentence; if against me, the "condition of our bargain is fulfilled, 66 and you have no plea left for your delay, after having pleaded and gained a "caufe. To which Euathlus anfwered.

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O most wife mafter, I might have a"voided the force of your argument, by not pleading my own caufe. But, giving up this advantage, do you not fee, "that whatever fentence the judges pafs, "I am fafe? If they give fentence for I am acquitted by their fentence; if against me, the condition of our bar

"me,

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gain is not fulfilled, by my pleading a caufe, and lofing it. The judges, think❝ing the arguments unanfwerable on "both-fides, put off the cause to a long "day"

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