The greatest thing in the small compass is a sound mind in a human body. Strive with all your body to be a lover of toil, and with your soul to be a lover of wisdom, in order that with the one you may have the strength to carry out your resolves, and with the other the intelligence to foresee what is for your good.
μέγιστον γὰρ ἐν ἐλαχίστῳ νοῦς ἀγαθὸς ἐν ἀνθρώπου σώματι. πειρῶ τῷ σώματι μὲν εἶναι φιλόπονος, τῇ δὲ ψυχῇ φιλόσοφος, ἵνα τῷ μὲν ἐπιτελεῖν δύνῃ τὰ δόξαντα, τῇ δὲ προορᾶν ἐπίστῃ τὰ συμφέροντα.
Original text (Ancient Greek)