EN 1105a7-13 It is more difficult to fight against pleasure than against spirit

ἔτι δὲ χαλεπώτερον ἡδονῇ μάχεσθαι ἢ θυμῷ, καθάπερ φησὶν Ἡράκλειτος, περὶ δὲ τὸ χαλεπώτερον ἀεὶ καὶ τέχνη γίνεται καὶ ἀρετή· καὶ γὰρ τὸ εὖ βέλτιον ἐν τούτῳ. ὥστε καὶ διὰ τοῦτο περὶ ἡδονὰς καὶ λύπας πᾶσα ἡ πραγματεία καὶ τῇ ἀρετῇ καὶ τῇ πολιτικῇ· ὁ μὲν γὰρ εὖ τούτοις χρώμενος ἀγαθὸς ἔσται, ὁ δὲ κακῶς κακός. ὅτι μὲν οὖν ἐστὶν ἡ ἀρετὴ περὶ ἡδονὰς καὶ λύπας, καὶ ὅτι ἐξ ὧν γίνεται, ὑπὸ τούτων καὶ αὔξεται καὶ φθείρεται μὴ ὡσαύτως γινομένων, καὶ ὅτι ἐξ ὧν ἐγένετο, περὶ ταῦτα καὶ ἐνεργεῖ, εἰρήσθω.