The Importance of Clarity: Philostratus, Discourse 1

“Clarity is a good rule for all speech, but especially for a letter. Regardless of whether we are assenting or begging, relenting or not, laying blame or defending, or even in love, we persuade more easily if we explain ourselves clearly. We will explain ourselves clearly and without being vulgar if we phrase common sentiments uniquely and new thoughts in familiar ways.”

… σαφήνεια δὲ ἀγαθὴ μὲν ἡγεμὼν ἅπαντος λόγου, μάλιστα δὲ ἐπιστολῆς· καὶ γὰρ διδόντες καὶ δεόμενοι καὶ ξυγχωροῦντες καὶ μὴ καὶ καθαπτόμενοι καὶ ἀπολογούμενοι καὶ ἐρῶντες ῥᾷον πείσομεν, ἢν σαφῶς ἑρμηνεύσωμεν· σαφῶς δὲ ἑρμηνεύσομεν καὶ ἔξω εὐτελείας, ἢν τῶν νοηθέντων τὰ μὲν κοινὰ καινῶς φράσωμεν, τὰ δὲ καινὰ κοινῶς.

Eunapius, Lives of the Philosophers 4.1.9: On the Clarity of Porphyry

“Although some philosophers conceal their teachings in obscure phrase, just as poets hide theirs in myth, Porphyry praised clarity as a cure-all, and because he had sampled it in his own experience, he inscribed it in his work and brought it back to daylight.”

τῶν δὲ φιλοσόφων τὰ ἀπόρρητα καλυπτόντων ἀσαφείᾳ, καθάπερ τῶν ποιητῶν τοῖς μύθοις, ὁ Πορφύριος τὸ φάρμακον τῆς σαφηνείας ἐπαινέσας καὶ διὰ πείρας γευσάμενος, ὑπόμνημα γράψας εἰς φῶς ἤγαγεν.

Eunapius?