The argument from the mirror. A companion to 7.24, with the move reversed. There the face was evidence against the soul (the grimace betrays and entrenches the passion); here it is a reproachful model: the face knows how to obey — it "takes shape and adornment" (σχηματίζεσθαι καὶ κατακοσμεῖσθαι) as the διάνοια commands. Everyone commands his features at least enough to hold a decent expression before others. The αἰσχρόν — the "disgrace" — lies in the asymmetry: the muscle obeys the mind, and the mind does not obey itself; the soul has power over the face, and, it would seem, none over its own person.

Self-formation. The precision is in the reflexive construction: αὐτὴν ὑφ’ ἑαυτῆς — the soul must receive its form "from itself," not from circumstances and not from spectators. The same verb κατακοσμεῖν — "to adorn, set in order" — returns the adornment theme of 7.31 (φαίδρυνον σεαυτόν): the true cosmetics are inward. In the background, the soul dyed by its thoughts (5.16: the soul takes the colour of its impressions): since the soul's form comes from somewhere in any case, the only question is who the sculptor is — you, or stray impressions. It is the demand of the discipline of assent in its pure form: govern your judgments with at least the diligence with which you govern your face. Cf. also 7.16 (the ruling part "turns itself" by itself) and 6.30 ("mould yourself"). The discipline is assent.