Simon Barker

Sometimes we disagree because of fundamental differences in what we treat as reasons for belief. Such are ‘deep disagreements'. Amongst the questions we might ask about deep disagreement is the epistemic normative one: how ought one to respond to disagreement, when that disagreement is deep. This paper addresses that question. According to the position developed, how one ought to respond to deep disagreement depends upon two things: (i) Whether one remains, in the context of disagreement, permitted to trust oneself in following one's epistemic norms and in relation to that (ii) whether one has the shared stock of social-epistemic experiences with followers of one's rival's norms such that one could reasonably be expected to see their way of doing things as a genuine epistemic alternative to one's own. Section 1 introduces a model of deep disagreement such that deep disagreements occur when disputants disagree because they follow different epistemic norms. Section 2 surveys the possible theoretical stances to take towards the epistemic-normative question. Section 3 develops an account of what it is to follow an epistemic norm. Section 4 applies this conception of norm-following to the epistemic-normative question. Section 5 discusses two points of clarification.

This paper discusses the normative structure of principles that require belief-revision in the face of disagreement, the role of self-trust in our epistemic lives, and the tensions that arise between the two. Section 2 argues that revisionary principles of disagreement share a general normative structure such that they prohibit continued reliance upon the practices via which one came to hold the beliefs under dispute. Section 3 describes an affective mode of epistemic self-trust that can be characterised as one’s having an attitude of optimism about the reliability of the practices via which one forms beliefs. The availability of affective self-trust is crucial to being able to rationally resist doubts about those practices. However, as argued in the final section of the paper, following revisionary principles of disagreement can render such trust psychologically unavailable. Consequently, attempts to follow such principles can have doxastic consequences that predictably exceed their normative implications