In this chapter, I argue, drawing primarily on passages from the Philebus, the Republic and the Laws, that Plato understands comedy to be, in essence, an imitation of laughable people, where the notion of the laughable, or to geloion, is a normative one that picks out what genuinely merits laughter, and not necessarily what people actually laugh at. According to Plato, the only thing that merits laughter is moral vice, in particular the vice of self-ignorance. I formulate four constraints on ideal comedy on Plato’s behalf: the veridical constraint, which holds that only what is genuinely laughable, that is, moral vice, should be imitated as laughable; the educative constraint, which holds that comedic imitation must aim at educating the audience by encouraging them to reject vice in their own lives; the emotional constraint, which holds that the comedic imitation should cause appropriate and appropriately moderate emotional reactions; and the political constraint, which holds that only moral and political enemies should be portrayed as laughable.