    When we select things that are according to nature and reject things that are contrary to nature, our actions are appropriate (kathêkonta; for Marcus’ use of this term, see i.2, iii.1.2, iii.16.2, vi.22, vi.26.3), and an appropriate action is an action for which there is a reasonable (eulogon) justification. An appropriate action counts as a morally perfect or virtuous action (katorthôma) when it is done from understanding, i.e., from the wise and stable cognitive state possessed only by the fully virtuous person (Arius Didymus 8).  Although the talk of the appropriate action having a reasonable justification might suggest that more than one action could be appropriate for a situation, or that what is appropriate could be relativized to the ordinary person’s grasp of the situation (as some utilitarians consider that action right which maximizes expected rather than actual utility), so that ‘reasonable justification’ would be like the law’s ‘reasonable doubt’ or ‘reasonable person’, the Stoics’ use of ‘reasonable’ in other contexts, such as the definition of the good emotions (eupatheiai) (Diogenes Laertius vii.116), the end (Arius Didymus 6a), and the virtues of reasoning and rhetoric (SVF iii.264, 268; 291, 294), clearly takes the standard of reasonableness to be the right reason of the fully virtuous person.  This points to there being only one appropriate action per situation, a conclusion which is confirmed by Chrysippus’ claim that the fully virtuous person performs all appropriate actions and leaves no appropriate action unperformed (iii.510). (This discussion of the ‘reasonable’ and appropriate action follows Brennan 1996, 326–29.) 