Akrasia

This chapter argues that epistemic akrasia is rationally permissible. The first task is to describe just what akrasia comes to. Loosely speaking, it is having a belief and thinking one should not have this belief, but there are three importantly different ways to make this precise. Unlike in the previous chapter, there is a systematic reason why none of these will pose a problem to normative externalism. There is no kind of akrasia that is licensed by normative externalism that is not made independently plausible by the failure of evidence to be, in Timothy Williamson’s sense, luminous. All of the arguments against akrasia work equally well, or perhaps we should say equally poorly, as arguments against the luminosity of evidence. The chapter ends with a discussion of the desire as belief arguments, and in particular with an argument that luminosity failures threaten the idea that expected values can be in any way guiding.