Delusions Are Beliefs (Just Not the Kind You Thought)

The idea that delusions are beliefs is supported by the observation that delusions, similarly to beliefs, are used in reasoning. However, delusions also exhibit other features that are difficult to explain under this doxastic view—they strongly resist evidence and sometimes conflict with an agent’s actions (in ways in which beliefs seemingly do not), giving rise to what is known as the double bookkeeping phenomenon. These features have motivated non-doxastic views, arguing that delusions are other types of mental phenomena (e.g., imaginings or empty speech acts). While these non-doxastic views account for the features of delusions like evidence resistance and double bookkeeping, they struggle to explain the belief-like features of delusions. We are thus at an impasse, where neither the doxastic nor the non-doxastic account of delusions can explain all the features of delusions. In this paper, I aim to make progress in this debate by showing that the doxastic view can, after all, account for both the belief-like and the other features of delusions. Drawing on recent literature in epistemology, I argue that (rational) beliefs can be motivated by non-evidential (e.g., pragmatic and emotional) factors, and that these factors help explain delusions’ otherwise puzzling features. I also propose that categorizing beliefs across two functional compartments, the implicit and the explicit, is helpful for understanding the dynamic interplay of delusions and non-delusional beliefs.