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in any

logism. A remarkable property of this kind is, that it may sometimes be happily retorted: it is, it seems, like a hand-grenade, which by dextrous management may be thrown back, so as to spend its force upon the assailant.

We shall conclude this tedious account of fyllogilins, with a dilemma mentioned by A. Gellius, and from him by many logicians, as insoluble other

way. “ Euathlus, a rich young man, desirous “ of learning the art of pleading, applied

10 Protagoras, a celebrated fophift, to “ instruct him, promising a great sum of

money as his reward; one half of which

was paid down; the other half he “ bound himself to pay as foon as he ! should plead a cause before the judges,

and gain it. Protagoras found him a

very apt scholar; but, after he had " made good progress, he was in no halte

to plead causes. The master, concei

ving that he intended by this means to “ fhift off his second payment, took, as “ he thought, a fure method to get the “ better of his delay. He sued Euathlus “ before the judges; and, having opened “ his cause at the bar, he pleaded to this Vol. III.

“ purpose.

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“ purpose. O most foolish young man,

do you not see, that, in any event, I “ must gain my point? for if the judges “ give sentence for me, you must pay by

their fentence; if against me, the con“ dition of our bargain is fulfilled, and

you have no plea left for your delay, “ after having pleaded and gained a cause. “ To which Euathlus answered. O molt " wise master, I might have avoided the « force of your argument, by not plead“ ing my own cause. But, giving up this

advantage, do you not see, that what

ever sentence the judges pass, I am safe? “ If they give sentence for me, I am acso quitted by their fentence ; if against

me, the condition of our bargain is not “ fulfilled, by my pleading a cause, and

losing it. The judges, thinking the arguments unanswerable on both fides, put off the cause to a long day.”


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Account of the remaining books of the


SECT. I. Of the Last Analytics.


IN the First Analytics, fyllogisms are con

sidered in respect of their form ; they are now to be considered in respect of their

The form lies in the necessary connection between the premises and the conclufion; and where such a connection is wanting, they are said to be informal, or vicious in point of form. But where there is no fault in the form,

be in the matter; that is, in the propositions of which they are composed, which may be true or false, probable or improbable.

When the premises are certain, and the conclusion drawn from them in due form, this is demonstration, and produces science. Such fyllogisms are called apodica


there may

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tical; and are handled in the two books of the Last Analytics. When the premises are not certain, but probable only, such fyllogisms are called dialectical; and of them he treats in the eiglit books of the Topics. But there are some fyllogisms which seem to be perfect both in matter and form, when they are not really fo: as, a face may seem beautiful which is but painted. These being apt to deceive, and produce a false opinion, are called sophistical; and they are the subject of the book concerning Sophisms.

To return to the Last Analytics, which treat of demonstration and of science: We fhall not pretend to abridge these books ; for Aristotle's writings do not admit of abridgement: no man in fewer words can say what he says; and he is not often guilty of repetition. We shall only give fome of his capital conclusions, omitting his long reasonings and nice distinctions, of which his genius was wonderfully productive.

All demonstration must be built upon principles already known; and these upon others of the same kind; until we come at last to first principles, which neither

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can be demonstrated, nor need to be, being evident of themselves.

We cannot demonstrate things in a circle, supporting the conclusion by the premises, and the premises by the conclufion. Nor can there be an infinite number of middle terms between the first principle and the conclusion.

In all demonstration, the first principles, the conclusion, and all the intermediate propositions, must be necessary, general, and eternal truths: for of things fortuitous, contingent, or mutable, or of individual things, there is no demonstration.

Some demonstrations prove only, that the thing is thus affected; others prove, why it is thus affected. The former may be drawn from a remote cause, or from an effect: but the latter must be drawn from an immediate cause; and are the most perfect.

The first figure is best adapted to demonstration, because it affords conclufions universally affirmative; and this figure is commonly used by the mathematicians.

The demonstration of an affirmative proposition is preferable to that of a nega


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