§9.31.1Ἀταραξία μὲν περὶ τὰ ἀπὸ τῆς ἐκτὸς αἰτίας συμβαίνοντα, δικαιότης δὲ ἐν τοῖς παρὰ τὴν ἐκ σοῦ αἰτίαν ἐνεργουμένοις· τουτέστιν, ὁρμὴ καὶ πρᾶξις καταλήγουσα ἐπ’ αὐτὸ τὸ κοινωνικῶς πρᾶξαι ὡς τοῦτό σοι κατὰ φύσιν ὄν.
Tranquility regarding those things which happen from an external cause, and justice in those things which are done through the cause which proceeds from yourself; that is to say, impulse and action terminating in this very thing, namely acting socially, as this is in accordance with your nature.