Plutarch, Sayings of Romans 207c-d (Augustus 7)
The ancient equivalent of taking a deep breath and counting to ten.
Ἀθηνοδώρῳ δὲ τῷ φιλοσόφῳ διὰ γῆρας εἰς οἶκον ἀφεθῆναι δεηθέντι συνεχώρησεν. ἐπεὶ δὲ ἀσπασάμενος αὐτὸν ὁ Ἀθηνόδωρος εἶπεν, “ὅταν ὀργισθῇς, Καῖσαρ, μηδὲν εἴπῃς μηδὲ ποιήσῃς πρότερον ἢ τὰ εἰκοσι καὶ τέτταρα γράμματα διελθεῖν πρὸς ἑαυτόν,” ἐπιλαβόμενος αὐτοῦ τῆς χειρός, “ἔτι σοῦ παρόντος,” ἔφη, “χρείαν ἔχω”, καὶ κατέσχεν αὐτὸν ἐνιαυτὸν ὅλον, εἴπων ὅτι “ἔστι καὶ σιγῆς ἀκίνδυνον γέρας.”
He granted the request of the philosopher Athenodorus, who asked to be allowed to return home because of his old age. But when Athenodorus was taking his leave he said, ‘Whenever you get angry, Caesar, say nothing and do nothing before you have run through the twenty-four letters of the alphabet to yourself.’ Augustus seized hold of his hand and said, ‘I still need you to be here!’ and kept him for a whole year, saying ‘The reward of silence is a lack of risk’ [Simonides, fr. 582].