Abnormal Certainty: Examining the Epistemological Status of Delusional Beliefs

This article intends to reconsider the epistemological status of delusional beliefs on the basis of Wittgenstein's conception of certainty. Several works over the last two decades have compared delusional beliefs with so-called hinge propositions, which - according to Wittgenstein - function as expressions of objective certainty. This gives rise to a paradox. On the one hand, delusions are compatible to Wittgensteinian certainties in some respects; on the other hand, they contradict beliefs shared by other members of the community, which makes them different from normal' certainties. In order to address this issue, I use Moyal-Sharrock's taxonomy of hinge propositions. This taxonomy allows one to distinguish between different types of hinge propositions; all types share the same features, but these features are manifested in a variety of ways. Thus, delusional beliefs might also be regarded as constituting a specific type of hinge propositions. This move makes it possible to resolve the paradox and to identify the special epistemic features of delusional beliefs.