[184] Aristot. De Generat. Animal. II. i. p. 731, b. 20, seq.; De Animâ, II. iv. p. 415, a. 26, seq.; Œconomica, I. iii. p. 1343, b. 23.
We have already stated that Noûs — Intellect — the noëtic function — is that faculty of the soul that correlates with the abstract and universal; with Form apart from Matter. Its process is at once analytical, synthetical, and retentive. Nature presents to us only concretes and particulars, in a perpetual course of change and reciprocal action; in these the abstract and universal are immersed, and out of these they have to be disengaged by logical analysis. That the abstract is a derivative from the concrete, and the universal from particulars — is the doctrine of Aristotle. Ascending from particulars, the analysis is carried so far that at length it can go no farther. It continues to divide until it comes to indivisibles, or simple notions, the highest abstractions, and the largest universals. These are the elements out of which universal propositions are formed, the first premisses or principia of demonstration. Unphilosophical minds do not reach these indivisibles at all: but it is the function of the theorizing Noûs to fasten on them, and combine them into true propositions. In so far as regards the indivisibles themselves, falsehood is out of the question, and truth also, since they affirm nothing. The mind either apprehends them, or it does not apprehend them: there is no other alternative.[185] But, when combined into affirmative propositions, they then are true or false, as the case may be. The formal essence of each object is among these indivisibles, and is apprehended as such by the intellect; which, while confining itself to such essence, is unerring, as each sense is in regard to its own appropriate perceivables.[186] But, when the intellect goes father, and proceeds to predicate any attribute respecting the essence, then it becomes liable to error, as sense is when drawing inferences.
[185] Aristot. De Animâ, III. vi. p. 430, a. 26: ἡ μὲν οὖν τῶν ἀδιαιρέτων νόησις ἐν τούτοις περὶ ἃ οὐκ ἔστι τὸ ψεῦδος· ἐν οἷς δὲ καὶ τὸ ψεῦδος καὶ τὸ ἀληθές, σύνθεσίς τις ἤδη νοημάτων ὥσπερ ἓν ὄντων. — Metaphysica, Θ. x. p. 1051, b. 31: περὶ ταῦτα οὐκ ἔστιν ἀπατηθῆναι, ἀλλ’ ἢ νοεῖν ἢ μή.
[186] Aristot. De Animâ, III. vi. p. 430, b. 29. This portion of the treatise is peculiarly confused and difficult to understand.
One of the chief functions that Aristotle assigns to Noûs, or the noëtic function, is that the principia of demonstration and knowledge belong to it; and not merely the principia, but also, in cases of action preceded by deliberation and balance of motives, the ultimate application of principia to action. So that he styles Noûs both beginning and end; also the beginning of the beginning; and, moreover, he declares it to be always right and unerring — equal to Science and even more than Science.[187] These are high praises, conveying little information, and not reconcilable with other passages wherein he speaks of the exercise of the noëtic function (τὸ νοεῖν) as sometimes right, sometimes wrong.[188] But, for the question of psychology, the point to be determined is, in what sense he meant that principia belonged to Noûs. He certainly did not mean that the first principles of reasoning were novelties originated, suggested, or introduced into the soul by noëtic influence. Not only he does not say this, but he takes pains to impress the exact contrary. In passages cited a few pages back, he declares that Noûs in entering the soul brings nothing whatever with it; that it is an universal potentiality — a capacity in regard to truth, but nothing more;[189] that it is in fact a capacity not merely for comparing and judging (to both of which he recognizes even the sentient soul as competent), but also for combining many into one, and resolving the apparent one into several; for abstracting, generalizing, and selecting among the phantasms present, which of them should be attended to, and which should be left out of attention.[190] Such is his opinion about the noëtic function; and he states explicitly that the abstract and universal not only arise from the concrete and particular, but are inseparable from the same really — separable only logically.
[187] Aristot. Ethic. Nikomach. VI. xii. p. 1143, a. 25, b. 10: διὸ καὶ ἀρχὴ καὶ τέλος νοῦς. — Analyt. Post. II. xviii. p. 100, b. 5.
[188] Aristot. De Animâ, III. iii. p. 427, b. 8: ἀλλ’ οὐδὲ τὸ νοεῖν, ἐν ᾧ ἔστι τὸ ὀρθῶς καὶ μὴ ὀρθῶς — διανοεῖσθαι δ’ ἐνδέχεται καὶ ψευδῶς.
[189] Ibid. I. ii. p. 404, a. 30, where he censures Demokritus: οὐ δὴ χρῆται τῷ νῷ ὡς δυνάμει τινὶ περὶ τὴν ἀλήθειαν, ἀλλὰ ταὐτὸ λέγει ψυχὴν καὶ νοῦν. — Compare ibid. III. iv. p. 429, a. 21, b. 30.
[190] Aristot. De Animâ, III. vi. p. 430, b. 5: τὸ δὲ ἓν ποιοῦν, τοῦτο ὁ νοῦς ἕκαστον. — Ibid. xi. p. 434, a. 9.
He describes, at the end of the Analytica Posteriora and elsewhere, the steps whereby the mind ascends gradually from sense, memory, and experience, to general principles. And he indicates a curious contrast between these and the noëtic functions. Sense, memory, phantasy, reminiscence, are movements of the body as well as of the soul; our thoughts and feelings come and go, none of them remaining long. But the noëtic process is the reverse of this; it is an arrest of all this mental movement, a detention of the fugitive thoughts, a subsidence from perturbation — so that the attention dwells steadily and for some time on the same matters.[191] Analysis, selection, and concentration of attention, are the real characteristics of the Aristotelian Noûs. It is not (as some philosophers have thought) a source of new general truths, let into the soul by a separate door, and independent of experience as well as transcending experience.