support, however, of this pofition I shall avail myself of the opinion and authority of another of the Peripatetic's ardent admirers, who has informed us That the discovery of the nature of Truth does not feem to have been made, at leaft by the philofophers of Greece, till Ariftotle wrote his book of Analytics, the profeffed defign of which is to fhew what SCIENCE and DEMONSTRATIVE TRUTH is.'

с

The Obfervation, then, which I have to make upon this comparative view of the works of Ariftotle, is, that as the Poetics contain the philofophy or rationale of two fpecies of POETRY, and the Rhetoric the philofophy or rationale of ORATORY, and deliver the laws and rules by which the most successful productions in both these departments were constructed; fo we may conclude by strict analogy, that the Analytics of the fame author is the philofophy or rationale of DEMONSTRATION, inveftigating its principles, and delivering the laws and rules by

• Ancient Metaphyfics, vol. 1. p. 374.

which it has been conducted, and may be advantageously continued. So that, if what is advanced in these lectures in regard to the KINDS OF TRUTH, their different Principles, Reasoning and Conftitution, be at all founded, this part of his ORGANON is no more calculated to fupply the Rule or Art by which Reason can push on its enquiries in Phyfics, Ethics, and all other parts of learning from which Demonstration is excluded, than his Rhetoric is the Rule or Art of writing a Poem, or his Poetic is the Rule or Art of compofing an Oration; or than the plan of a Bridge exhibits the Rule or Art of building a Church, or any other Means in nature can be the Rule or Art of producing an effect, to which they do not properly belong.

SYLLOGISM forms profeffedly the whole scope and burden of this celebrated work; which, as may be expected from this view of its origin, is peculiarly adapted, if not almost exclusively confined, to that species of Reasoning which is properly demonftrative.

See chap. iv. fect. 2. and chap. vii. fect. 2. of this volume.

Though the Prior Analytics affect to treat of Probable and Sophiftical, as well as of Neceffary

In his First Analytics, where he delivers the doctrine of Syllogifm in general, Ariftotle divides it into three claffes which he calls Figures, according to the Predication and Subjection of the middle Term: Each of which Figures he fubdivides into a certain number of legitimate Moods according to the Quantity and Quality of the Premifes. And this forms the whole plan of his Logic. The first of these Figures is, however, not only the leading one, but the most important, and involves all the merit of the other two; for all their legitimate Moods, as well as thofe of a fourth invented afterwards by Galen, are reducible to fome of the Moods of the first Figure, and derive their proof and authority from that reduction. See Analyt. Prior. cap. 23, 24. Now the reafoning in the First Figure is absolutely Demonftrative ; and Ariftotle obferves, that all Mathematical Reasoning is reducible to fyllogifms of the First Figure. Τῶν δὲ σχημάτων ἐπισημονικὸν μάλισα τὸ πρῶτόν ἐσιν. Αἵ τε γὰρ μαθηματικαὶ τῶν ἐπισημῶν διὰ τούτου φέρουσι τὰς ἀποδείξεις" οἷον αριθμητική, καὶ γεωμετρία, καὶ ὀπτικὴ, καὶ σχεδόν [ὡς εἰπεῖν] ὅσαι τῇ διότι ποιένται τήν σκέψιν. ἢ γὰρ ὅλως, ἢ ὡς ἐπὶ τὸ πολὺ, καὶ ἐν τοῖς πλείςοις, διὰ τούτου τᾶ σχήματος ὁ τὸ διότι γινέται συλ λογισμός.

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Ὥσε κἂν διὰ τῆτ ̓ εἴη μάλισα ἐπισημονικόν. κυριώτατον γὰρ τῇ εἰδέναι, τὸ διότι θεωρεῖν. Εἶτα τὴν τῇ τί ἐσιν ἐπισ σήμην, διὰ τέτου μίνα θηρεῦσαι δυνατόν. ἐν μὲν γὰρ τῷ μέσω σχήματι 8 γενέται κατηγορικὸς συλλογισμὸς· ἡ δὲ τᾶ τί ἐσιν ἐπισήμη, καταφάσεως. ἐν δὲ τῷ ἐσχάτῳ γίνεται μὲν, ἀλλ' ἐ καθόλο· τὸ δὲ τί ἐσι, τῶν καθόλα ἐσιν' ε γὰρ

or Demonftrative, fyllogifms; it is the laft whose principles are fo accurately and fuccessfully analyzed, and which are exhibited in the Pofterior, with fo much force of genius and labour of investigation, as fpringing from an infallible foundation, raifing an immense system of abstract and general truths all fortified by demonftration, and rifing ftory upon story into a moft luminous and extenfive fabric.

But although his Poetics, whatever might be the expectation of the Stagyrite, were never able to make a Poet, or his Rhetoric an Orator, however excellent these criticisms may be, without that native force of genius. and vigor of imagination, the first and indifpenfable ingredients, which they may indeed correct and improve, but never can supply;

πῇ ἐσι ζῶον δίπουν ὁ ἄνθρωπος. Ἔτι τᾶτο μὲν ἐκείνων οὐδὲν προσδεῖται ἐκεινα δὲ διὰ τατα καταπυκνᾶται, καὶ αὔξεται, ἕως ἂν εἰς τὰ ἄμεσα ἔλθῃ. Φανερὸν οἶον, ὅτι κυριώτατον τῶ ἐπίσασθαι τὸ πρῶτον ἐςι σχῆμα. Analyt. Poft. lib. i.

So that we here plainly fee the intimate and, indeed, neceffary connection between Syllogifm and Demonftration; both of which he had extracted from Mathematics.

he

he refolved, with a bold and enterprizing mind, though on weaker grounds of expectation, that his Syllogifm, which he had conftructed with fo much labour on fo firm a bafis, fhould form an UNIVERSAL REASONER, and conduct him with facility and fuccefs in the fearch and illustration of probable Truth through all parts of learning.

any

His fagacity foon difcovered that Axioms or Maxims, which are general. Propofitions, were, in the first place, to be formed, as they are in Mathematics, from which the media or arguments were to be drawn; before fyllogiftic Reasoning could be applied, in of the departments of probable learning, as the guide to truth. In his analyfis of demonftrative reafoning he had feen the wonderful and immediate effect, which the univerfal Form or Category of Quantity had in the production of Axioms or felf-evident truths, as the Principles of fyllogiftic argument; and he cherished the hope (and, when great philofo

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Ἥμεν πρόθεσις τῆς πραγματείας, μέθοδον εὐρεῖν, ἀφ' ἧς δυνησόμεθα συλλογίζεσθαι περὶ παντὸς τῇ προτεθέντα @golańμarC, ¿1⁄2 ivdowv. Ariftot. Top. lib. i. cap. I. phers