Delusions, Illusions and Inference under Uncertainty


  • Thanks to the editors and contributors to this issue for valuable comments on earlier drafts.

Address for correspondence: Department of Philosophy, Monash University, Clayton, VIC 3800, Australia.



Three challenges to a unified understanding of delusions emerge from Radden's On Delusion (2011). Here, I propose that in order to respond to these challenges, and to work towards a unifying framework for delusions, we should see delusions as arising in inference under uncertainty. This proposal is based on the observation that delusions in key respects are surprisingly like perceptual illusions, and it is developed further by focusing particularly on individual differences in uncertainty expectations.