Τῶν ὄντων τὰ μέν ἐστιν ἐφ' ἡμῖν, τὰ δὲ οὐκ ἐφ' ἡμῖν. ἐφ' ἡμῖν μὲν ὑπόληψις, ὁρμή, ὄρεξις, ἔκκλισις καὶ ἑνὶ λόγῳ ὅσα ἡμέτερα ἔργα· οὐκ ἐφ' ἡμῖν δὲ τὸ σῶμα, ἡ κτῆσις, δόξαι, ἀρχαὶ καὶ ἑνὶ λόγῳ ὅσα οὐχ ἡμέτερα ἔργα. καὶ τὰ μὲν ἐφ' ἡμῖν ἐστι φύσει ἐλεύθερα, ἀκώλυτα, ἀπαραπόδιστα, τὰ δὲ οὐκ ἐφ' ἡμῖν ἀσθενῆ, δοῦλα, κωλυτά, ἀλλότρια. Επίκτητος: Εγχειρίδιον