Grading Modal Judgement

Abstract

AbstractThis paper proposes a new model of graded modal judgement. It begins by problematizing the phenomenon: given plausible constraints on the logic of epistemic modality, it is impossible to model graded attitudes toward modal claims as judgements of probability targeting epistemically modal propositions. This paper considers two alternative models, on which modal operators are non-proposition-forming: (1) Moss (2015), in which graded attitudes toward modal claims are represented as judgements of probability targeting a ‘proxy’ proposition, belief in which would underwrite belief in the modal claim; (2) a model on which graded attitudes toward modal claims are represented as judgements of credence taking as their objects (non-propositional) modal representations (rather than proxy propositions). The second model, like Moss’s model, is shown to be semantically and mathematically tractable. The second model, however, can be straightforwardly integrated into a plausible model of the role of graded attitudes toward modal claims in cognition and normative epistemology.