Hinge-certainty and the asymmetricality of ‘deep moral disagreement’

Abstract The idea of deep disagreement, as a peculiarly distinct kind of disagreement, was seminally introduced by Fogelin. His diagnosis of the problems posed by deep disagreement was based on what at the time was the unappreciated insight and wisdom of Wittgenstein’s On Certainty (1969). Many epistemologists of deep disagreement nowadays draw on the flourishing research programme of hinge epistemology that derives from On Certainty, and define deep disagreement as a clash of conflicting ‘hinge commitments’. The idea that deep moral disagreement is a distinct subset of deep disagreement, grounded on conflicting moral hinge commitments, has recently come to the fore. This paper critically examines the plausibility of that idea, and the adequacy of hinge epistemologists’ deployment of the concept of hinge commitment to the analysis of deep disagreement. I argue that hinge epistemologists of deep disagreement disregard, ignore, or conflate key distinctions between subjective and objective certainty, and universal and local certainty, in their conception and deployment of the concept of hinge commitment. With the aid of these distinctions, I reveal the individualistic assumptions and framework that epistemologists project onto the idea of deep moral disagreement, and argue that ‘objective’ hinge-certainty is a social property of ways of life, rather than of individual psyches. The paper culminates with a demonstration of why, and how, deep moral disagreements are asymmetrically deep, and disagreements not ‘in opinions but in form of life’ (Wittgenstein in Philosophical investigations. Blackwell, Oxford, 1968, § 241).