For the Stoics, the good is what benefits and cannot be put to evil use; strictly speaking, the only good is TERMvirtue (ἀρετή) and what partakes in it. Everything external — health, wealth, reputation — belongs to the indifferents (ἀδιάφορα), though it may be "preferred" (προηγμένον). The good is inseparable from the fine (καλόν): what is good is also noble.

SVF III 74–77 (Chrysippus); DL VII 94–101; Stob. Ecl. II 69–70 W; LS 60. In Marcus: Med. 2.1; 2.11; 05-12 (what the many think good is no good: test it by imagining its possessor); 05-15; 05-16 (the good of the rational being lies in the rational-social soul); 05-37 (the good is good turns of soul, impulses, deeds); 06-30; 06-41; 06-51; 07-15 (ἐμὲ δεῖ ἀγαθὸν εἶναι — whatever anyone does, I must be good, as the emerald keeps its colour); 07-26 (what the wrongdoer took for ἀγαθόν — the root of his offence); 07-59 (ἔνδον ἡ πηγὴ τοῦ ἀγαθοῦ — the spring of good is within); 08-01 (the good — only what makes one just, temperate, brave, free); 08-05 (ἀγαθόν σε ἄνθρωπον εἶναι δεῖ — you must be a good man); 08-10 (pleasure is not ἀγαθόν — the syllogism from repentance); 08-14 (a man's doctrines about ἀγαθά and κακά explain his acts); 08-20 (neither "good" for the ball to rise nor "harm" to fall — phases of a natural motion); 09-16 (the ἀγαθόν of a rational being is in ἐνέργεια, not in what is undergone); 09-17 (to the stone the rise is no ἀγαθόν, the fall no evil: the external is indifferent); 09-41 (τὸ ἴδιον ἀγαθὸν τηροῦσα — the διάνοια keeps its own good while sharing the motions of the flesh); 10-01 (ἀγαθὴ καὶ ἁπλῆ καὶ μία καὶ γυμνή — the four predicates wished upon the soul); 10-08 (ἀγαθός — first of the six names, to be borne rather than received from others); 10-16 (enough of discussing what ὁ ἀγαθὸς ἀνήρ is like — be one); 10-30 (ἀργύριον ἀγαθὸν εἶναι κρίνων — your anger grew from the same false valuation of the good as his fault did); 10-32 (Μηδενὶ ἐξέστω εἰπεῖν ἀληθεύοντι περὶ σοῦ ὅτι οὐκ ἀγαθός — the demand bears not on report but on fact: let whoever says it be lying); 11-05 (Τίς σου ἡ τέχνη; ἀγαθὸν εἶναι — "to be good" is named a craft, one with a subject matter and an apprenticeship); 11-15 (ὁ ἁπλοῦς καὶ ἀγαθός must be as noticeable as "a man who reeks": simplicity cannot be announced, but neither can it be hidden). In Book XII — 12-23 (the ending of life is called not merely "no evil" but ἀγαθόν, if for the whole it is timely, advantageous and borne along with it). And further in Book XII: 12-29 (the enjoyment of life is to fasten one ἀγαθόν to the next without a gap); 12-34 (the argument from the Epicureans, for whom pleasure is called the good); 12-35 (τὸ εὔκαιρον μόνον ἀγαθόν — only the timely is good). In Books I–IV: 02-03, 02-07, 02-11, 02-13; 03-06 (τὸ ἀγαθὸν ἐκεῖνο, τὸ ἴδιον καὶ τὸ σόν — "that good which is your own and yours"); 04-10 and 04-17 (ἀγαθὸς γενοῦ — "become good," in the imperative), 04-25 (ἀγαθοῦ ἀνθρώπου), 04-42.

In passage 02-01 Marcus relies on the classical Stoic identification of the good with the fine (καλόν): "the nature of the good is that it is fine; the nature of evil, that it is shameful." This knowledge — knowledge of the very TERMnature of good and evil — frees the sage from being harmed, because genuine harm is possible only in the sphere of TERMevil, that is, of vice, and vice cannot be imposed from outside (see no-harm-to-virtuous). See also 11-21 (τὰ τοῖς πλείοσι δοκοῦντα ἀγαθά — the many’s opinions about the good are not of one kind, and only the "common" ones will serve as the ground of an aim).