Stanford Encyclopedia of Philosophy
First published Fri Sep 23, 2011
In this entry, we explore a particular strategy that we might deploy when we wish to establish an epistemic norm such as Probabilism or Conditionalization. It is called epistemic utility theory, or sometimes cognitive decision theory. I will use the former. Epistemic utility theory is inspired by traditional utility theory, so let's begin with a quick summary of that.
Traditional utility theory (also known as decision theory) explores a particular strategy for establishing the norms that govern which actions it is rational for us to perform in a given situation. The framework for the theory includes states of the world, actions, and, for each agent, a utility function, which takes a state of the world and an action and returns a measure of the extent to which the agent values the outcome of performing that action at that world. We call this measure the utility of the outcome at the world.
[...] we might say that an agent ought to perform an action that has maximal expected utility, where the expected utility of an action is obtained by weighting its utility at each state of the world by the credence assigned to that state of the world, and summing. This norm is called Maximize Expected Utility.