Abstract
Among psychiatric conditions, delusions have received significant attention in the philosophical literature. This is partly due to the fact that many delusions are bizarre, and their contents interesting in and of themselves. But the disproportionate attention is also due to the notion that by studying what happens when perception, cognition, and belief go wrong, we can better understand what happens when these go right. In this paper, I attend to delusions for the second reason—by evaluating the epistemology of delusions, we can better understand the epistemology of ordinary belief. More specifically, given recent advancements in our understanding of how delusions are formed, the epistemology of delusions motivates a proper functionalist account of the justification of belief. Proper functionalist accounts of the justification of belief hold that whether a belief is justified is partly determined by whether the system that produces the belief is functioning properly. Whatever pathology is responsible for delusion formation, restoring it to its proper function resolves the epistemic condition, an effect which motivates proper functionalism.
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Notes
This is not to say that delusional beliefs are lacking entirely epistemic value. Recently, some authors have argued that monothematic delusions are epistemically innocent, which is an epistemic property of states that are epistemically faulty but nevertheless confer some epistemic benefit [3, 22, 26].
John Turri argues that doxastic justification explains propositional justification, which is contrary to the orthodox view that the order of explanation goes the other way [27]. Even so, his view wouldn’t permit an irrationally held justified belief.
Thanks to an anonymous referee for this example.
I adopt ‘proper function’ rather than perhaps a more common terminology, ‘etiological function,’ out of convenience, as the epistemological theory (i.e., proper functionalism) adopts this language.
This is obviously true for accounts such as reliabilism or proper functionalism. But even internalist accounts propose some grounding condition on the belief.
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Crutchfield, P. Delusion, Proper Function, and Justification. Neuroethics 14, 113–124 (2021). https://doi.org/10.1007/s12152-020-09429-5
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DOI: https://doi.org/10.1007/s12152-020-09429-5