Political theory is not a purely theoretical enterprise; it is intended to be practical and action-guiding. To perform this role, the requirements of political theory must be possible, and the standard of possibility it employs must be appropriate to the political domain. Because human beings vary in their capacity for morality and justice, a reasonably just society, as Rawls understands it, must not be expected. Despite his concerns to the contrary, the possibility of a just polity is not needed to ward off resignation and cynicism. There is a principled path between a politics of complacency that thwarts feasible progress and a politics of utopian aspiration that ends by inflicting harm in the name of doing good.