[167] See Sext. Math. viii. 11: οἱ ἀπὸ τῆς στοᾶς, τρία φάμενοι συζυγεῖν ἀλλήλοις, τό τε σημαινόμενον καὶ τὸ σημαῖνον καὶ τὸ τυγχάνον. ὧν σημαῖνον μὲν εἶναι τὴν φωνὴν ... σημαινόμενον δὲ αὐτὸ τὸ πρᾶγμα τὸ ὑπ’ αὐτῆς δηλούμενον ... τυγχάνον δὲ τὸ ἐκτὸς ὑποκείμενον ... τούτων δὲ δύο μὲν εἶναι σώματα, καθάπερ τὴν φωνὴν καὶ τὸ τυγχάνον, ἓν δὲ ἀσώματον, ὥσπερ τὸ σημαινόμενον πρᾶγμα καὶ λεκτόν. Sen. Ep. 117, 13, giving it expressly as the teaching of the Stoics, not as his own: Sunt, inquit, naturæ corporum ... has deinde sequuntur motus animorum enuntiativi corporum—for instance, I see Cato walk—corpus est, quod video.... Dico deinde: Cato ambulat. Non corpus est, inquit, quod nunc loquor, sed enuntiativum quiddam de corpore, quod alii effatum vocant, alii enuntiatum, alii edoctum. Compare also on the λεκτόν Sext. Math. viii. 70 (above p. 83, 2); Pyrrh. iii. 52. Various arguments are used by the Stoics to prove that the voice as opposed to utterance (λεκτὸν) is material, as has been said. p. 74, 5. Illustrative of the distinction between utterance and the process of thought is the assertion (in Sext. Pyrrh. ii. 81) that certainty as being a definite condition of the soul is material, but that truth itself is not material: λέγεται διαφέρειν τῆς ἀληθείας τὸ ἀληθὲς τριχῶς, οὐσίᾳ, συστάσει, δυνάμει· οὐσίᾳ μὲν, ἐπεὶ τὸ μὲν ἀληθὲς ἀσώματόν ἐστιν, ἀξίωμα γάρ ἐστι καὶ λεκτὸν, ἡ δὲ ἀλήθεια σῶμα, ἔστι γὰρ ἐπιστήμη πάντων ἀληθῶν ἀποφαντικὴ, ἡ δὲ ἐπιστήμη πὼς ἔχον ἡγεμονικόν (Id. Math. vii. 38, a similar statement is expressly attributed to a Stoic); likewise a similar statement which Sen. Ep. 117, discusses, and at length declares to be a mere quibble, but not till after a lengthy refutation: sapientiam bonum esse, sapere bonum non esse. The statement rests on the assertion that nothing can be a good which does not make itself felt, and nothing can make itself felt which is not material; wisdom is material, because it is mens perfecta, but sapere is incorporale et accidens alteri, i.e. sapientiæ. Accordingly, λεκτὸν (as Ammon. De Inter. 15, b, remarks) is a μέσον τοῦ τε νοήματος καὶ τοῦ πράγματος· if, however, νόημα be taken to express the thought itself, and not the process of thinking, it becomes identical with λεκτόν. Conf. Simpl. Cat. 3, α, Basil.: τὰ δὲ λεγόμενα καὶ λεκτὰ τὰ νοήματά ἐστιν, ὡς καὶ τοῖς Στωϊκοῖς ἐδόκει. In Plut. Plac. iv. 11, 4, a definition of νόημα or ἐννόημα is given similar to that of λεκτὸν in Sext. Math. viii. 70: φάντασμα διανοίας λογικοῦ ζῴου. See above p. 84, 4. The statement, however, of Philop. Anal. Pr. lx. a, Schol. in Ar. 170, a, 2, cannot be true, that the Stoics called things τυγχάνοντα, thoughts ἐκφορικὰ, and sounds λεκτά, whereas ἐκφορικὸν may be used of thoughts in the same sense as λεκτόν.