δὶς γὰρ καὶ τρίς: this proverb is ascribed to Empedocles. Plato employs it also in Phil. 59 e, where we read: τὸ δὶς καὶ τρὶς τό γε καλῶς ἔχον ἐπαναπολεῖν τῷ λόγῳ. Cf. Soph. Phil. 1238 “δὶς ταὐτὰ βούλει καὶ τρὶς ἀναπολεῖν μ᾽ ἔπη”. The first καί means also, and its force extends over both members, as Phaedo 63 e ἐνίοτε ἀναγκάζεσθαι καὶ δὶς καὶ τρὶς πίνειν τούς τι τοιοῦτον ποιοῦντας.