man is the best instrument of truth, dialectic was exaggerated into a universal science of everything that is. Aristotle, on the other hand, learnt to distinguish dialectic (διαλεκτική) from science (ἐπιστήμη); in that it has no definite subject, else it would not ask questions (Post. An. i. 11, 77 a 31-33); in that for appropriate principles it substitutes the probabilities of authority (τὰ ἔνδοξα) which are the opinions of all, or of the majority, or of the wise (Top. i. 1, 100 b 21-23); and in that it is not like science a deduction from true and primary principles of a definite subject to true consequences, but a deduction from opinion to opinion, which may be true or false. Sophistry appeared to him to be like it, except that it is a fallacious deduction either from merely apparent probabilities in its matter or itself merely apparently syllogistic in its form (cf. Topics, i. 1). Moreover, he compared dialectic and sophistry, on account of their generality, with primary philosophy in the Metaphysics (Γ 2, 1004 b 17-26); to the effect that all three concern themselves with all things, but that about everything metaphysics is scientific, dialectic tentative, sophistry apparent, not real. He means that a sophist like Protagoras will teach superficially anything as wisdom for money; and that even a dialectician like Plato will write a dialogue, such as the Republic, nominally about justice, but really about all things from the generality of the form of good, instead of from appropriate moral principles; but that a primary philosopher selects as a definite subject all things as such without interfering with the special sciences of different things each in its kind (Met. Γ 1), and investigates the axioms or common principles of things as things (ib. 3), without pretending, like Plato, to deduce from any common principle the special principles of each science (Post. An. i. 9, 32). Aristotle at once maintains the primacy of metaphysics and vindicates the independence of the special sciences. He is at the same time the only Greek philosopher who clearly discriminated discovery and disputation, science and dialectic, the knowledge of a definite subject from its appropriate principles and the discussion of anything whatever from opinions and authority. On one side he places science and philosophy, on the other dialectic and sophistry.
Such is the great mind of Aristotle manifested in the large map of learning, by which we have now to determine the order of his extant philosophical writings, with a view to studying them in their real order, which is neither chronological nor traditional, but philosophical and scientific. Turning over the pages of the Berlin edition, but passing over works which are perhaps spurious, we should put first and foremost speculative philosophy, and therein the primary philosophy of his Metaphysics (980 a 21-1093 b 29); then the secondary philosophy of his Physics, followed by his other physical works, general and biological, including among the latter the Historia Animalium as preparatory to the De Partibus Animalium, and the De Anima and Parva Naturalia, which he called “physical” but we call “psychological” (184 a 10-967 b 27); next, the practical philosophy of the Ethics, including the Eudemian Ethics and the Magna Moralia as earlier and the Nicomachean Ethics as later (1094-1249 b 25), and of the Politics (1252-1342), with the addition of the newly discovered Athenian Constitution as ancillary to it; finally, the productive science, or art, of the Rhetoric, including the earlier Rhetoric to Alexander and the later Rhetorical Art, and of the Poetics, which was unfinished (1354-end). This is the real order of Aristotle’s system, based on his own theory and classification of sciences.
But what has become of Logic, with which the traditional order of Andronicus begins Aristotle’s works (1-148 b 8)? So far from coming first, Logic comes nowhere in his classification of science. Aristotle was the founder of Logic; because, though others, and especially Plato, had made occasional remarks about reason (λόγος), Aristotle was the first to conceive it as a definite subject of investigation. As he says at the end of the Sophistical Elenchi on the syllogism, he had no predecessor, but took pains and laboured a long time in investigating it. Nobody, not even Plato, had discovered that the process of deduction is a combination of premisses (συλλογισμός) to produce a new conclusion. Aristotle, who made this great discovery, must have had great difficulty in developing the new investigation of reasoning processes out of dialectic, rhetoric, poetics, grammar, metaphysics, mathematics, physics and ethics; and in disengaging it from other kinds of learning. He got so far as gradually to write short discourses and long treatises, which we, not he, now arrange in the order of the Categories or names; the De Interpretatione on propositions; the Analytics, Prior on syllogism, Posterior on scientific syllogism; the Topics on dialectical syllogism; the Sophistici Elenchi on eristical or sophistical syllogism; and, except that he had hardly a logic of induction, he covered the ground. But after all this original research he got no further. First, he did not combine all these works into a system. He may have laid out the sequence of syllogisms from the Analytics onwards; but how about the Categories and the De Interpretatione? Secondly, he made no division of logic. In the Categories he distinguished names and propositions for the sake of the classification of names; in the De Interpretatione he distinguished nouns and verbs from sentences with a view to the enunciative sentence: in the Analytics he analysed the syllogism into premisses and premisses into terms and copula, for the purpose of syllogism. But he never called any of these a division of all logic. Thirdly, he had no one name for logic. In the Posterior Analytics (i. 22, 84 a 7-8) he distinguishes two modes of investigation, analytically (ἀναλυτικῶς) and logically (λογικῶς). But “analytical” means scientific inference from appropriate principles, and “logical” means dialectical inference from general considerations; and the former gives its name to the Analytics, the latter suits the Topics, while neither analytic nor logic is a name for all the works afterwards called logic. Fourthly, and consequently, he gave no place to any science embracing the whole of those works in his classification of science, but merely threw out the hint that we should know analytics before questioning the acceptance of the axioms of being (Met. Γ 3).
It is a commentator’s blunder to suppose that the founder of logic elaborated it into a system, and then applied it to the sciences. He really left the Peripatetics to combine his scattered discourses and treatises into a system, to call it logic, and logic Organon, and to put it first as the instrument of sciences; and it was the Stoics who first called logic a science, and assigned it the first place in their triple classification of science into logic, physics, ethics. Would Aristotle have consented? Would he not rather have given the first place to primary philosophy?