[134] Prantl, Geschichte der Logik, vol. i. pp. 428, 429; Simplikius ad Categor. fol. 43, A: κἀκεῖνο ἄτοπον τὸ σύνθετα ποιεῖν τὰ γένη ἐκ προτέρων τινῶν καὶ δευτέρων ὡς τὸ πρός τι ἐκ ποιοῦ καὶ πρός τι. Cf. Plotinus, Ennead. vi. 1, 25-29.
Porphyry appears to include all συμβεβηκότα under ποιὸν and πὼς ἔχον: he gives as examples of the latter, what Aristotle would have assigned to the Category κεῖσθαι (Eisagoge, cc. 2, 10; Schol. Br. p. 1, b. 32, p. 5, a. 30).
In comparing the ten Aristotelian with the four Stoic Categories we see that the first great difference is in the extent and comprehension of Quale, which Aristotle restricts on one side (by distinguishing from it Essentia Secunda), and enlarges on the other (by including in it many attributes accidental and foreign to the Essence). The second difference is, that the Stoics did not subdivide their third Category, but included therein all the matter of six Aristotelian Categories,[135] and much of the matter of the Aristotelian Quale. Both schemes agree on two points:— 1. In taking as the point of departure the concrete, particular, individual, Substance. 2. In the narrow, restricted, inadequate conception formed of the Relative — Ad Aliquid.
[135] Plotinus (Ennead. vi. 1. 80) disapproves greatly the number of disparates ranked under τὸ πὼς ἔχον, which has (he contends) no discoverable unity as a generic term. It is curious to see how he cites the Aristotelian Categories, as if the decuple distinction which they marked out were indefeasible.
Simplikius says that the Stoics distinguished between τὸ πρός τι and τὸ πρός τι πὼς ἔχον; and Trendelenburg, (pp. 228, 229) explains and illustrate this distinction, which, however, appears to be very obscure.
Plotinus himself recognizes five Summa or Prima Genera,[136] (he does not call them Categories) Ens, Motus, Quies, Idem, Diversum; the same as those enumerated in the Platonic Sophistes. He does not admit Quantum, Quale, or Ad Aliquid, to be Prima Genera; still less the other Aristotelian Categories. Moreover, he insists emphatically on the distinction between the intelligible and the sensible world, which distinction he censures Aristotle for neglecting. His five Genera he applies directly and principally to the intelligible world. For the sensible world he admits ultimately five Catgories; Substantia or Essentia (though he conceives this as fluctuating between Form, Matter, and the Compound of the two), Ad Aliquid, Quantum, Quale, Motus. But he doubts whether Quantum, Quale, and Motus, are not comprehended in Ad Aliquid.[137] He considers, moreover, that Sensible Substance is not Substance, properly speaking, but only an imitation thereof; a congeries of non-substantial elements, qualities and matter.[138] Dexippus,[139] in answering the objections of Plotinus, insists much on the difference between Aristotle’s point of view in the Categoriæ, in the Physica, and in the Metaphysica. In the Categoriæ, Aristotle dwells mainly on sensible substances (such as the vulgar understand) and the modes of naming and describing them.
[136] Plotinus, Ennead. vi. 2, 8, 14, 16.
[137] Plotinus, Ennead. vi. 3. 3. ἢ καὶ ταῦτα εἰς τὰ πρός τι· περιεκτικὸν γὰρ μᾶλλον. His idea of Relation is more comprehensive than that of Aristotle, for he declares that terms, propositions, discourse, &c., are πρός τι· καθ’ ὃ σημαντικά (vi. 3. 19).
[138] Ibid. vi. 3. 8-15.
[139] The second and third books of Dexippus’s Dialogue contain his answers to many of the objections urged by Plotinus. Aristotle, in the Categoriæ (Dexippus says), accommodates himself both to the received manner of speaking and to the simple or ordinary conception of οὐσία entertained by youth or unphilosophical men — οὔτε γὰρ περὶ τῶν ὄντων, οὔτε περὶ τῶν γενῶν τῆς πρώτης οὐσίας νῦν αὐτῷ πρόκειται λέγειν· στοχάζεται γὰρ τῶν νέων τοῖς ἁπλουστέροις ἐπακολουθεῖν δυναμένων (p. 49). Compare also pp. 50-54, where Dexippus contrasts the more abstruse handling which we read in the Physica and Metaphysica, with the more obvious and unpretending thoughts worked out by Aristotle in the Categoriæ. Dexippus gives an interesting piece of advice to his pupil, that he should vary his mode of discussing these topics, according as his companions are philosophical or otherwise — ἐγὼ μὲν οὖν, ὦ καλὲ κἀγαθὲ Σέλευκε, δογματικώτερον πρὸς Πλωτῖνον ἀπαντῶ, σὺ δέ, ἐπεὶ βαθύτεραί πως εἰσὶν αἱ λύσεις αὗται, πρὸς μὲν τοῦς ἐκ φιλοσοφίας ὁρμωμένους ταῖς τοιαύταις ἀπαντήσεσι χρῶ, πρὸς δὲ τοὺς ὀλίγα ἐπισταμένους τῶν δογμάτων ταῖς προχείροις χρῶ διαλύσεσιν, ἐκεῖνο λέγων, ὅτι περὶ πόδα ποιεῖσθαι ἔθος τὰς ἀκροάσεις Ἀριστοτέλει· διὸ καὶ νῦν οὐδὲν ἔξωθεν ἐπεισάγει τῶν ἀνωτέρω κειμένων φιλοσοφημάτων, &c. (pp. 50, 51).