Moral and Legal Implications of the Continuity between Delusional and Non-delusional Beliefs

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In this paper we explore two aspects of gradualism as they apply to the phenomenon of delusions, that is, the acknowledgement that it is difficult to distinguish pathological from non-pathological beliefs and the defence of the view that there is considerable continuity between delusional and other epistemically faulty beliefs. We also identify the implications of these two aspects of gradualism for questions about one’s moral and legal responsibility for action that is motivated by one’s delusional beliefs. In the first section of the paper, we argue that an effective demarcation between pathological and non-pathological beliefs cannot be successfully achieved on mere epistemic grounds, that is, on the basis of the epistemic quality of the relevant belief-forming and belief-maintaining processes. We offer some reasons to endorse the thesis that delusional beliefs are continuous with other epistemically faulty beliefs. In the second section of the paper, we examine the implications of the continuity thesis for the association—common in everyday thinking but also in ethical and legal frameworks—between being diagnosed with a psychiatric disorder featuring delusions and having reduced or no responsibility for action that is motivated by one’s delusions. We consider some interesting cases of agents who committed crimes related to the content of their epistemically faulty beliefs, and ask whether their beliefs qualifying as delusions makes a difference to whether such agents were responsible for their actions. Finally, we make some suggestions about how the continuity thesis can inform attributions of moral and legal responsibility for action.


Original languageEnglish
Title of host publicationVagueness in Psychiatry
EditorsGeert Keil, Lara Keuck, Rico Hauswald
Publication statusPublished - 3 Nov 2016

Publication series

NameInternational Perspectives in Philosophy and Psychiatry


  • delusions