Skip to main content
Skip banner

Web Content Display Web Content Display

INCET logo

Web Content Display Web Content Display

BIOUNCERTAINTY - ERC Starting Grant no. 805498

ERC logo

Web Content Display Web Content Display

Web Content Display Web Content Display

Delusional Experiences and Evidence

Delusional Experiences and Evidence

The research project "Delusional Experiences and Evidence" was funded by the POLONEZ BIS 2 competition, co-financed by the European Commission and the National Science Center under the Marie Skłodowska-Curie COFUND grant.

Basic informations

Project title: A formal treatment of epistemic injustice
Duration: April 1, 2023 - March 31, 2025
Principal investigator: dr Chenwei Nie (chenwei.nie@uj.edu.pl)
Mentor: dr hab. Tomasz Żuradzki, prof. UJ

Popularization description

This project proposes to develop a novel epistemological framework for understanding the interaction between
delusional experiences and evidence in the aetiology of delusional beliefs. Delusional beliefs are notorious for their
being incorrigible in light of conflicting evidence. In the literature, it is widely accepted that one of the key explanatory
factors may be patients’ delusional experiences. According to cognitive theories of delusions, patients’ delusional
experiences offer some flimsy evidence in support of their delusional beliefs. However, there is a growing recognition
that this creates a conundrum for cognitive theories: that is, how could it be that on the one hand patients are too
willing to form delusional beliefs on the basis of the flimsy evidence provided by their delusional experiences (overresponsive
to evidence), but on the other hand they fail to reject their delusional beliefs in the light of considerable
counterevidence (under-responsive to evidence) (Furl et al., 2022)? One promising way to solve the conundrum, which
this project will explore, is to argue that patients’ delusional experiences play a more significant role than offering some
flimsy evidence. Indeed, according to phenomenological theories of delusions, patients have a distinctive kind of
delusional experiences with the character of hyper-reality which might do more than offer flimsy evidence (Feyaerts et
al., 2021). However, phenomenological theories have been focusing on “understanding the variety of ways in which one
might experience delusions and the delusional world” (Sass & Pienkos, 2013, p. 632) and an epistemological account of
the interaction between delusional experiences and evidence is underdeveloped in the literature.


The primary aim of the project is to fill in this gap by developing an epistemological framework that will help us get a
better understanding of the interaction between delusional experiences and evidence. The framework will be built on
three working hypotheses. (1) Based on the phenomenal reading of Descartes (Paul, 2020), the first hypothesis this
project plans to pursue is that in many cases patients’ delusional experiences may be a pathological form of what
Descartes calls clear experiences that causally compel assent. (2) Based on phenomenal conservatism (Siegel & Silins,
2015), the second hypothesis this project plans to pursue is that patients’ delusional experiences may offer some prima
facie justification, but the justification would be undermined in the presence of counterevidence. (3) Inspired by the
recent work on mental causation (Campbell, 2020), the third hypothesis this project plans to pursue is that the causal
relationship between delusional experiences and delusional beliefs is primitive in the sense that it is not dependent on
the justificatory relationship between them. With these three hypotheses, delusions will become understandable in the
following sense: in many cases, even though the justificatory force of a patient’s delusional experience would be
undermined in the presence of counterevidence, the primitive causal force of the patient’s delusional experience may
persist and causally compel the patient’s assent.


Not only will the framework be valuable for researchers interested in delusions, but it will also make important
contributions to overcoming epistemic injustices in clinical practice. It has been argued that apart from negative
stereotypes, another main contributory factor of epistemic injustice is the lack of theoretical resources for patients to
express their experiences and for clinical professionals to value patients’ descriptions of their experiences (Crichton et
al., 2017; Ritunnano, 2022). The secondary aim of the project is to investigate ways the framework may help eliminate
epistemic injustices. The hypothesis is that in many cases, the framework may be a promising candidate for the missing
theoretical resource for eliminating testimonial injustice and hermeneutical injustice.


The project has four main objectives: (1) to offer a way to solve the conundrum faced by cognitive theories; (2) to
develop phenomenologists’ insight that patients’ delusional experiences are a distinctive kind; (3) to offer a new way to
integrate cognitive theories and phenomenological theories into a unified framework; (4) to overcome epistemic
injustices in clinical practice.

Web Content Display Web Content Display

Recent publications

New paper by Chenwei Nie

New paper by Chenwei Nie

Chenwei Nie published a new article: "Revisiting Maher’s one-factor theory of delusion” in Neuroethics. This paper is a part of Delusional Experiences and Evidence project.
Read More o New paper by Chenwei Nie

Web Content Display Web Content Display

(2023). Can a Bodily Theorist of Pain Speak Mandarin?. Philosophia 51, 261–272 (2023). https://doi.org/10.1007/s11406-021-00353-3
(2019). Continuing commentary: challenges or misunderstandings? A defence of the two-factor theory against the challenges to its logic. Cognitive Neuropsychiatry, 24(4), 300-307. https://doi.org/10.1080/13546805.2019.1652156
(2016). Delusional beliefs, two-factor theories, and bizarreness. Frontiers of Philosophy in China, 11(2), 263-278. https://doi.org/10.3868/s030-005-016-0020-1

Web Content Display Web Content Display

Źródło finansowania

This project is being carried out at the Interdisciplinary Centre for Ethics at Jagiellonian University. Although the Centre is part of the Faculty of Philosophy, and cooperates closely with the Institute of Philosophy, it is an interdisciplinary enterprise: the Centre’s Academic Board includes representatives of several university faculties.  We use an interdisciplinary approach that bridges the gap between philosophical ethics and other disciplines, such as psychology, medicine, legal studies and economics; we utilize “armchair” methods typical for the humanities, as well as social science (conceptual analysis, case studies) and empirical methods (behavioral experiments, corpus analysis, topic modelling). See more information about INCET 

 

This research is part of the project No. 2021/43/P/HS1/02247 co-funded by the National Science Centre and the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 945339.

Acronym: DelusionalExperience