What are delusions? Examining the typology problem.

Summary

Delusions are a varied phenomenon across psychiatric conditions, especially common in schizophrenia. A core philosophical debate, the typology problem, asks what kind of mental state underlies delusional reports—whether they are beliefs (doxastic) or something else (anti-doxastic). This paper critically reviews the scattered literature on this issue. It clarifies two main philosophical approaches (interpretivism and functionalism) and introduces new subcategories: revisionist and non-revisionist doxastic views, and commonsensical and non-commonsensical anti-doxastic views. The analysis concludes by highlighting fundamental unresolved challenges in the debate, which has implications for experimental psychiatry and psychotherapy development.

Study at a glance

Abstract

Delusions are a heterogenous transdiagnostic phenomenon with a higher prevalence in schizophrenia. One of the most fundamental debates surrounding the philosophical understanding of delusions concerns the question about the type of mental state in which reports that we label as delusional are grounded, namely, the typology problem. The formulation of potential answers for this problem seems to have important repercussions for experimental research in clinical psychiatry and the development of psychotherapeutic tools for the treatment of delusions in clinical psychology. Problematically, such alternatives are scattered in the literature, making it difficult to follow the current development and state of the target discussion. This paper offers an updated critical examination of the alternatives to the typology problem currently available in the literature. After clarifying the two main philosophical views underlying the dominant formulation of the debate (interpretivism and functionalism), we follow the usual distinction between doxastic (the idea that delusions are a type of belief) and anti-doxastic views. We then introduce two new sub-distinctions; on the doxastic camp, we distinguish between revisionist and non-revisionist proposals; on the anti-doxastic camp, we distinguish between commonsensical and non-commonsensical anti-doxasticisms. After analyzing the main claims of each view, we conclude with some of the most fundamental challenges that remain open within the discussion. This article is categorized under: Philosophy > Foundations of Cognitive Science Philosophy > Consciousness Philosophy > Psychological Capacities Neuroscience > Cognition.