Critias agrees that Socrates should try to cure not just Charmides's headache, but also his soul. Charmides is then praised both by Critias (for his temperance) and Socrates (for his illustrious family heritage). Socrates proceeds to point out that, if all this praise and noble heritage is true, then Charmides has no need of the "charm" that makes the soul temperate—he only needs the "leaf" part of the cure. Socrates asks Charmides if this is indeed the case. Charmides blushes (which, Socrates tells us, only makes him more beautiful), and answers that he can't really say: to say he's not temperate of soul would be an untoward self-accusation, and would go against Critias's claims; but to claim such temperance would be boastful and therefore indicate "ill manners."
Socrates proposes an "inquiry" to determine whether or not Charmides is already temperate of soul—this way, Charmides won't have to answer himself. Charmides agrees to give it a try, giving Socrates free reign. The discussion begins with Socrates proposing that, if Charmides has temperance, then he must have some notion of what that is, some "intimation of her nature and qualities." After some hesitation, Charmides answers that temperance is a matter of doing everything "quietly"; thus, temperance is a kind of quietness.
Socrates argues that temperance is surely to be found in the "noble and good" (at this point, true dialogue begins, with Socrates framing his arguments in the form of brief questions, to which Charmides generally just assents). But in things like writing, reading, musicianship, and wrestling, quickness and sharpness are good and noble, whereas "quietness and slowness" are "bad and unsightly." Thus, "in reference to the body" especially, quickness rather than quietness will be more temperate (since temperance is a good). The same dominance of quickness and energy holds for learning, teaching, remembering, understanding, deliberation and discovery, and so on; "is not cleverness," Socrates asks, "a quickness of the soul?"
With this line of argument, then, quietness is dismissed as the definition of temperance. Socrates asks Charmides to try again. Charmides makes a "manly effort," and comes up with modesty as the new definition. Socrates points out that Homer (in the Odyssey, at 17.347) says, "Modesty is not good for a needy man." Thus, modesty is at least sometimes not good, and so cannot define temperance (which Charmides has agreed is always good).
Charmides suddenly recalls something that someone told him about temperance: "Temperance is doing our own business." Socrates, after some brief, inconclusive questions about where Charmides heard this, claims that it is a kind of riddle: "whoever uttered [this definition] seems to have meant one thing, and said another." Asked why this is the case, Socrates cites the example of the schoolmaster who asks students to write down names of both enemies and friends, since his aim in writing them is merely to teach writing. The students are doing nothing intemperate in this case, even though they are not doing just their own business (because they are not writing just their own names and that of the schoolmaster). The same difficulty holds in many cases of "doing" (of which writing is one): a state which compelled men to wash only their own clothing and dishes (in their entirety), for example, would be an intemperate, poorly-ordered state.
Thus, whatever philosopher gave the "doing our own business" definition must, unless he was a fool, have had a "hidden meaning." Charmides admits that he doesn't know what this might be; he can no longer say what "doing one's own business" really means.