Prescribing Institutions Without Ideal Theory*

P OLITICAL philosophers are not shy to prescribe ways to design social and political institutions so as to eradicate or at least mitigate various actual injustices. The conventional wisdom is that such prescriptions are the province of nonideal theory but that ideal theory is required as a guide for nonideal theory. On this view, our first task is to specify fully just principles of regulation-that is, principles that regulate the constitution of fully just institutional arrangements. 1 These principles subsequently guide and constrain our attempts to prescribe institutional solutions to address actual injustices. 2 Call this the ideal guidance approach to institutional design. This view is mistaken, or so I will argue. Ideal theory does not yield guiding principles that actual institutions must aim to realize, even if only approximately. Fortunately, the conventional wisdom is also avoidable.