Epistemic utility theory

One of the central projects of formal epistemology concerns the formulation and justification of epistemic norms. The project has three stages: First, the formal epistemologist produces a mathematical model of an agent’s epistemic states—call this the descriptive stage. Next, she formulates, in terms of this model, putative norms that she claims govern these states—call this the normative stage. Finally, she provides a justification for these norms—call this the justificatory stage. It is one of the great virtues of formal epistemology that the final justificatory stage can be made mathematically precise. The strategy is this: the formal epistemologist states an epistemic norm that is taken to be more general and fundamental than those given in the normative stage; this norm is then formulated in terms of the mathematical model provided by the descriptive stage; and the norms posited in the normative stage are derived from this fundamental norm by means of a mathematical theorem.