The problem of policymaker ignorance is logically prior to the problem that has traditionally, if mistakenly, been conceived as the primary problem of politics, namely the problem of policymaker incentives. Indeed, it is a general fact about all human action, in and out of the political realm, that ignorance constrains what can be deliberately achieved via action. I offer two arguments for this conclusion, one based on simple introspection and another based on the meaning of the widely held principle that ought implies can. Beyond the limits of policymaker knowledge are policy objectives that can be realized only if spontaneous forces intervene. Political-epistemological inquiry promises to clarify the goals that can and cannot be achieved via political action and thus promises to improve the quality of political decision-making and limit constituent disappointment.