Abstract

Normal agents in the actual world are limited: they cannot think about all the options that are available to them—or even about all options that are available to them according to their evidence. Moreover, agents cannot choose an option unless they have thought about that option. Such agents can be irrational in two ways: either by making their choice too quickly, without canvassing enough options, or by wasting time canvassing ever more options when they have already thought of enough options. This chapter proposes an account of this kind of rationality for limited agents. To be rational, such agents need a kind of background sensitivity to whether or not continuing to search for more options has greater expected value than deciding right away. According to this proposal, it is the unavoidable predicament of choice that all rational decision-making depends on the unconscious operation of mental dispositions.