Aphes

Ὅ τί ποτε τοῦτό εἰμι, σαρκία ἐστὶ καὶ πνευμάτιον καὶ τὸ ἡγεμονικόν. ἄφες τὰ βιβλία· μηκέτι σπῶ· οὐ δέδοται. ἀλλ’ ὡς ἤδη ἀποθνήσκων τῶν μὲν σαρκίων καταφρόνησον· λύθρος καὶ ὀστάρια καὶ κροκύφαντος, ἐκ νεύρων, φλεβίων, ἀρτηριῶν πλεγμάτιον. θέασαι δὲ καὶ τὸ πνεῦμα, ὁποῖόν τί ἐστιν· ἄνεμος· οὐδὲ ἀεὶ τὸ αὐτό,ἀλλὰ πάσης ὥρας ἐξεμούμενον καὶ πάλιν ῥοφούμενον. τρίτον οὖν ἐστὶ τὸ ἡγεμονικόν. ὧδε ἐπινοήθητι· γέρων εἶ· μηκέτι τοῦτο ἐάσῃς δουλεῦσαι, μηκέτι καθ’ ὁρμὴν ἀκοινώτητον νευροσπαστηθῆναι, μηκέτι τὸ εἱμαρμένον ἢ παρὸν δυσχερᾶναι ἢ μέλλον ἀποδύρεσθαι.
(Marcus Aurelius, Ta eis heauton 2.2)

What makes up this being of mine is flesh, and a bit of breath and the ruling centre. Put down your books—do not distract yourself with them any more; that is not granted to you. As if you were on the point of death, despise the flesh—just blood, bones, and the network of nerves, veins, and arteries. Consider what sort of thing breath is: a stream of air, and not always the same, but at each moment belched out and drawn in again. The third part of you is the ruling centre. Look at it this way: you are an old man; no longer allow this part of you to be enslaved any more; no longer allow it to be tugged this way and that like a puppet by each unsociable motive; no longer allow it to be discontented with its present fate or to flinch from its future one. (tr. Christopher Gill)