Delusions

In February or March 2023, I went shopping for a mother's day card. I could not find any at a local shop and made an inquiry at the counter. The till worked said there were none. I picked up a card which said, "To my wife," brought it to the counter and said, "This might work for someone," alluding to the Oedipus myth. Pleased with my joke, I bought the card. I put it on a mattress next to mine and (...) also another curious card I found. In April 2023, I found they were missing and contacted the police. I asked them if an ELECTRONIC bug could be sent under the door of my apartment and remove the card. In September 2023, I was admitted to North Manchester General Hospital with mental health difficulties and my question was used as evidence of severe mental disorder. I said (a) that the bug question expressed a hypothesis, not a belief; and (b) I abandoned the hypothesis after talking to the police. (From my earlier reading on philosophy of psychiatry, delusions are supposed to be robust: the delusional subject does not abandon them. By the way, Sean Crawford, alarmed, said: you are working on that now!) I was troubled by the fact that my hypothesis was taken as evidence of paranoia and repeatedly asserted its status as hypothesis, but the consultant psychiatrist said that most people don't consider such a hypothesis. (Through my sister in October 2023, I learnt of another psychiatric response: "you acted on the hypothesis - you called the police." But the cards have never been found: it was entirely reasonable for me to call the police and I had other hypotheses, such as ordinary theft. By the way, it is not as if I am married and the to-my-wife card is normal in my home. NONE of these people asked about what was lost and whether it was found.) In a previous contribution, I have raised a concern about the NMGH consultant psychiatrist's appeal to what is normal versus my hypothesis (entitled "Hypotheses as evidence for madness, Humeans"). Here I will raise much the same concern with different detail: if you work in various areas of philosophy, you may well entertain hypotheses that are NOT normally considered in this situation going by statistics. Consider epistemology and philosophy of science, the second area being one I regularly write in. And you might naively introduce one of the less statistically normal hypotheses to a police officer, but certainly not one out-there by the standards of philosophy (evil demons manipulating your perceptual experience, brains-in-vats, etc.). This is especially likely if you believe your work to be of practical relevance, contrary to the common image of philosophy. (By the way, various philosophers would argue that it is rational, given our commonsense starting point, to ignore demons and brains-in-vats hypotheses, BUT do any think it is rational to ignore the electronic bug hypothesis in my 2023 position? The extent to which these people incentivize conformity to an extremely narrow standard of normality, by light or heavy means! "No, it's just for you in that situation." Really? I believe pastoral-lover Elizabeth Gaskell kept a cow in her garden in industrial Manchester!). (shrink)

This paper presents a different objection to the "neo-Kantian" idea of alternative systems of concepts for organizing the same sensory content. In any actual case that is plausibly this, the content (the experience or the pre-experiential sensory input) received by others with an alternative system is actually significantly different. I refer to social anthropology as a source of the objection but the objection as developed there is rejected by British anthropologists. I also appeal to my supposedly psychotic experience to support (...) the objection, but the support is still insufficient. (shrink)

A large and growing body of research in computational psychiatry draws on Bayesian modelling to illuminate the dysfunctions and aberrations that underlie psychiatric disorders. After identifying the chief attractions of this research programme, we argue that its typical focus on abstract, domain-general inferential processes is likely to obscure many of the distinctive ways in which the human mind can break down and malfunction. We illustrate this by appeal to psychosis and the social phenomenology of delusions.

Introduction: Cotard delusion—the delusional belief “I am dead”—is named after the French psychiatrist who first described it: Jules Cotard (1880, 1882). Ramachandran and Blakeslee (1998) proposed that the idea “I am dead” comes to mind when a neuropathological condition has resulted in complete abolition of emotional responsivity to the world. The idea would arise as a putative explanation: if “I am dead” were true, there would be no emotional responsivity to the world. Methods: We scrutinised the literature on people who (...) expressed the delusional belief “I am dead”, looking for data on whether such patients are reported as entirely lacking in emotional responsivity. Results: In numerous cases, patients with Cotard delusion are described as experiencing emotions including anxiety, fear, guilt, distress, euphoria and worry. Conclusions: We conclude that complete absence of emotional responsivity cannot be what prompts the delusional idea that one is dead. We propose that, in at least some cases, the idea “I am dead” comes to mind in response to symptoms of depersonalisation or derealisation, often present in cases of Cotard delusion, and give examples of Cotard patients with abnormalities in various neural areas that could be responsible for the presence of such symptoms. (shrink)

A growing number of studies in both the scientific and the philosophical literature have drawn on a Bayesian predictive processing framework to account for the formation of delusions. The key here is that delusions form because of disrupted prediction error signalling. Parrott’s recent critique argues that the framework is incomplete in two respects: it leaves unclear why delusional hypotheses are selected over none at all or over more plausible alternatives; it leaves unclear how exactly it is that delusional hypotheses are (...) generated in the first place. In this paper, we defend the framework’s explanatory power by way of showing how it can go a long way in helping disentangle these concerns. We take up each of them in turn. As for the first, our argument turns on two claims: a) believing nothing, although possible in principle, may not be a viable procedure in the circumstances; b) alternative hypotheses may be rendered unavailable for selection, due to aberrant prediction errors. As for the second concern, we distinguish three ways in which delusional hypotheses may be initially acquired, all of which are based on experience broadly construed. (shrink)

Reasoning that leads to delusions—especially in schizophrenia—appears beyond the bounds of sense, profoundly inaccessible. By analyzing empirical research on reasoning that supports delusions in schizophrenia, I demonstrate that such reasoning can be made intelligible at the personal level. Specifically, I propose that these empirical findings can be positively characterized as reflecting a distinctive epistemic style—a unique implementation of reason rather than its absence. Delusion-supporting reasoning in schizophrenia can be understood as expressing epistemic values and preferences characteristic of a maverick epistemic (...) personality. As such, it is substantially intelligible in light of these underlying values. Further, I argue that the presence of this epistemic style in individuals with schizophrenia can itself be understood in light of their anomalous experiences and social exclusion. This view contributes to reducing stigma and provides new resources for theorizing non-standard interactions with evidence within the neurodiversity paradigm. (shrink)

Current frameworks propose that delusions result from aberrant belief updating due to altered prediction error (PE) signaling and misestimation of environmental volatility. We aimed to investigate whether behavioral and neural signatures of belief updating are specifically related to the presence of delusions or generally associated with manifest schizophrenia.Our cross-sectional design includes human participants (nfemale/male=6625/41), stratified into four groups: healthy participants with minimal (n=22) or strong delusional-like ideation (n=18), and participants with diagnosed schizophrenia with minimal (n=13) or strong delusions (n=13), resulting (...) in a 2x2 design, which allows to test for the effects of delusion and diagnosis. Participants performed a reversal learning task with stable and volatile task contingencies during fMRI scanning. We formalized learning with a hierarchical Gaussian filter model and conducted model-based fMRI analysis regarding beliefs of outcome uncertainty and volatility, precision-weighted PEs of the outcome- and the volatility-belief.Patients with schizophrenia as compared to healthy controls showed lower accuracy and heightened choice switching, while delusional ideation did not affect these measures. Participants with delusions showed increased precision-weighted PE-related neural activation in fronto-striatal regions. People with diagnosed schizophrenia overestimated environmental volatility and showed an attenuated neural representation of volatility in the anterior insula, medial frontal and angular gyrus.Delusional beliefs are associated with altered striatal PE-signals. Juxtaposing, the potentially unsettling belief that the environment is constantly changing and weaker neural encoding of this subjective volatility seems to be associated with manifest schizophrenia, but not with the presence of delusional ideation. (shrink)

Wouter Kusters argues that madness has much to offer philosophy, as does philosophy to madness. In this paper, i support both claims by drawing on a mad phenomenon which I label Radical Psychotic Doubt, or RPD. First, although skepticism is a minority position in epistemology, it has been claimed that anti-skeptical arguments remain unsatisfying. I argue that this complaint can be clarified and strengthened by showing that anti-skeptical arguments are irrelevant to RPD sufferers. Second, there's a debate about whether so-called (...) hinge commitments are beliefs or not. I argue that RPD can be used to strengthen the case that they are. Moreover, if hinges are beliefs, some madpeople are more epistemically rational than some sane philosophers. Third, drawing on my own mad experiences, I challenge evidentialism by presenting a better candidate for a truly forced cchoice about what to believe than William James' traditional religious example. I further show that in certain psychiatric contexts, evidentialism has more radical implications than Jamesian pragmatism, which comes out as more conservative. Finally, I discuss how philosophical theories like pragmatism and Pyrrhonism can provide inspiration for new and much-needed coping strategies for RPD sufferers. (shrink)

ABSTRACT Neurobiological foundations of delusional disorder (DD) have been studied less with neuroimaging techniques when compared to other psychotic disorders. The present study aimed to delineate the neural substrates of DD by investigating neuroanatomical characteristics of the corpus callosum (CC) with statistical shape analysis (SSA) conducted on magnetic resonance images (MRI). Twenty (female:male=1:1) DSM-5 DD patients and 20 age- and gender-matched healthy individuals were included. High-resolution 3D T1 Turbo Field Echo MRI images were scanned with a 1.5 T MR device. (...) The landmarks that were selected to determine the shape differences in CC were identified based on previous studies. Furthermore, constructed landmarks were determined and employed to better assess regional shape differences. There was no significant difference in the CC area in the mid-sagittal images between the DD patients and controls. However, DD patients exhibited a pattern of structural CC changes in various regions. The study findings emphasizes the variable subregional nature of CC in DD patients. Future SSA studies with larger samples could shed further light on DD etiology, diagnosis, classification and treatment options. (shrink)

How does it come about that a person akratically believes that P, while at the same time believing that the available evidence speaks against that P? Among the current accounts, Scanlon offers an intuitive suggestion that one’s seeming experience that P may play an important role in the aetiology of their akratic belief that P. However, it turns out to be quite challenging to articulate what the role of seeming experience is. This paper will offer a novel development of Scanlon’s (...) intuitive suggestion, with a focus on clear-eyed epistemic akrasia. I will argue that the primary role of seeming experience is unlikely to act as the subject’s reason or to provide the subject with prima facie justification; instead, based on the recent work in dogmatism and Cartesian clarity, I will propose a causal account, according to which, when it seems clear to the subject that P, the seeming experience may exert a brute causal force to persistently compel the subject to believe that P. This causal account also has the advantage of helping some existing accounts to explain clear-eyed epistemic akrasia. (shrink)

We all have experiences in which it “seems clear” to us that something is true. This kind of clear experience can play significant roles in determining whether we believe something to be true. But what are the significant roles? So far, the literature has focused on optimal cases where a person's clear experience might provide prima facie justification for their belief. This article will develop the hypothesis that, in less optimal cases, these clear experiences can be epistemically damaging. Specifically, it (...) will argue that, in certain cases, such experiences may causally compel belief even in the face of counterevidence. (shrink)

Delusional perception designates a sudden, idiosyncratic, and often self-referential delusion triggered by a neutral perceptual content. In classical psychopathology, delusional perception was considered almost pathognomonic for schizophrenia. Since delusional perception has been erased from ICD-11 and always been absent in DSM, it risks slipping out of clinical awareness. In this article, we explore the clinical roots of delusional perception, elucidate the psychopathological phenomenon, and discuss its two predominant conceptualizations, i.e., Schneider’s well-known two-link model and Matussek’s lesser known one-link model. The (...) two-link model posits that delusional perception amounts to an abnormal interpretation of an intact perception, whereas the one-link model posits that the delusional meaning is contained within a changed perception. Despite their differences, both models stress that delusional perception is a primary delusion that takes place within an altered experiential framework that is characteristic of the psychopathological Gestalt of schizophrenia. We discuss the role of delusional perception in future psychopathological and diagnostic assessment and argue that such assessments must be conducted in comprehensive manner, eliciting the psychopathological context within which symptoms and signs are embedded. Finally, we discuss the compatibility of the two models of delusional perception with contemporary cognitive models on delusion and cognitive psychotherapeutic approaches. (shrink)

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. (shrink)

How shall we distinguish religious delusion from sane religious belief? Making this determination is not usually found to be difficult in clinical practice – but what shall be our theoretical rationale? Attempts to answer this question often try to provide differentiating principles by which the religious “sheep” may be separated from the delusional “goats.” As we shall see, none of these attempts work. We may, however, ask whether the assumption underlying the search for a differentiating principle – that religious beliefs (...) and religious delusions can usefully be considered species of a common genus – is a good one. In this paper, we outline an alternative, “disjunctive,” understanding of religious belief and religious delusion. By reminding ourselves both of what is central to any delusion and of what distinguishes bona fide religious claims from their pretenders, we show how to resolve our reflective puzzlement about religious delusion without recourse to differentiating principles. (shrink)

In On Madness: Understanding the Psychotic Mind, published in 2022, Richard G.T. Gipps embarks on a philosophical exploration of psychosis. Generally speaking, Gipps’s book presents an approach he calls “apophatic psychopathology,” (Gipps 2022, 2) borrowing from negative (that is, apophatic) theology and its method of understanding God’s nature by seeing how it defeats the predication of even those most supreme qualities we are drawn to predicate of Him. Gipps’s central insight regarding psychotic phenomena is that we best come to understand (...) them not positively, by predicating of the psychotic subject this or that rationally intelligible, intentional state, but instead negatively, through seeing how such predications are here defeated. Sitting down with a person suffering from psychosis requires that we develop the capacity to stay with them in their brokenness, rather than projecting onto them an intentional structure that their illness has abrogated. Gipps comments critically on relativistic tendencies we encounter these days, concluding that people suffering from severe psychosis are not happily thought of as just living in an “alternative reality” as good as the one populated by nonpsychotic people. (shrink)

Who would buy a book full of interviews that can be accessed online? Perhaps only some bibliophile readers. Hence, a quick glance at "Conversations in Critical Psychiatry"—consisting of a significant portion of interviews with philosophers, clinicians, and researchers previously published in Psychiatric Times—might lead one to conclude that this volume is of little interest. But such a conclusion would be premature.

Delusions are usually depicted in one of two contrasting ways. They are either characterized as harmful and dysfunctional beliefs or as fostering engagement with the environment and sometimes even psychological wellbeing in the face of psychological or biological difficulties – something which, according to some accounts, would make them biologically adaptive. It is this “adaptive hypothesis” that I focus on in this paper, by empirically investigating the adaptiveness of delusions in a sample of people suffering from OCD. The paper shows (...) that delusions in OCD entertain complex and heterogeneous relationships with psychological wellbeing and engagement with the environment, highlighting some future directions that clinical and philosophical research on the topic should take. (shrink)

Bereavement has long been recognised as an experience of profound temporal disruption, unravelling and even severing the connections, meanings, and strategies we habitually use in navigating time. The technologies that are involved in our grieving and mourning processes can therefore also be temporal technologies; our encounters with them can both shape and be shaped by our entanglement in the temporalities of loss. The recent phenomenon of so-called ‘griefbots’ or ‘deathbots’ – Large Language Model-powered chatbots trained to imitate the dead – (...) is no different. This paper explores some of the implications that interactions with such bots might have for a bereaved person’s experience of time by turning to Heidegger’s conceptualisation of world-time. This framework is particularly useful for thinking about both intimacy and loss, and can shed light on both beneficial and deleterious consequences of griefbot usage. In particular, such an approach can show that the dangers of griefbots usage lie less in the potential for the bereaved being deceived, and more in the reductive perspective that these bots can encourage. Usage of, and even temporary reliance upon, a griefbot can generate attitudes with a protective effect, similar to the function that Lisa Bortolotti ascribes to delusions. However, griefbots can also interfere with the temporal unfolding of grief and mourning by disrupting the way that loss tends to transform our embedding within the dynamics of world-time. (shrink)

Philosophy is witnessing an “Agential Turn,” characterised by the thought that explaining certain distinctive features of human mentality requires conceiving of many mental phenomena as acts, and of subjects as their agents. We raise a challenge for three central explanatory appeals to mental agency––agentialism about doxastic responsibility, agentialism about doxastic self‐knowledge, and an agentialist explanation of the delusion of thought insertion: agentialists either commit themselves to implausibly strong claims about the kind of agency involved in the relevant phenomena, or make (...) appeals to agency which seem explanatorily redundant. The agentialist literature does not contain a clear answer to this Agentialist Dilemma, and we put it forward here as a core challenge for the Agential Turn. But we also accept the fundamental motivation behind the Agential Turn, its critique and rejection of a purely passivist and spectatorial conception of the human mind. We close by urging the recognition of a broader category of rational subjectivity, a category which includes states which are neither active nor passive, but nevertheless form part of a subject's rational point of view on the world. (shrink)

Delusions are defined by the DSM-IV as false beliefs about external reality. However, it is unclear whether introspective delusions, namely delusional beliefs that are wrong about one’s own experience, are also possible. One reason to doubt this comes from the fact that delusion and hallucinatory experience seem to go hand in hand, suggesting a strong relationship between the two. Empiricist theories argue that delusions arise from endorsing or explaining an anomalous experience. In this chapter, I will review the existing literature (...) on the relationship between experience and delusional belief, and spell out the consequences for the possibility of introspective delusions. I argue that the current understanding of the relationship between experience and delusional belief leaves space for the possibility of introspective delusions; however, as our methods to access experience independently from introspective reports are still imperfect, it is still controversial whether specific candidates like Anton-Babinski Syndrome might be introspective delusions. (shrink)

This commentary on Adam Pautz's excellent book, Perception, explores the consequences of “spatial illusionism,” the view that the spatial properties presented in experience aren't instantiated in the extra-mental world. First, I consider whether spatial illusionism entails that our ordinary beliefs about the physical world are mostly false. I then argue that spatial illusionism threatens to undermine two arguments Pautz's defends in Perception: his argument that sense data theory is incompatible with physicalism, and his central argument against the internal physical state (...) view of perception. (shrink)

We put forward a two-factor account of anosognosia for hemiplegia—more generally, anosognosia for motor impairments—considered as a delusion. Anosognosia is a patient’s lack of knowledge of their illness or impairment, and patients who lack knowledge of their motor impairments believe that they can still move limbs that are, in reality, paralysed. This belief fits the DSM-5 definition of delusion.In our two-factor account of anosognosia as a continued-belief delusion, the first factor—an impairment of the motor control system—results in an anomaly of (...) experience. When patients try, but fail, to move their left arm, there is an anomalous absence of immediate bodily experience of movement failure—perhaps accompanied by an illusory experience of successful movement. However, even without immediate experience of movement failure, other evidence of the motor impairments would be available—including evidence from everyday mishaps consequent on the motor impairments. The second factor in our two-factor account results in patients being unable to use this evidence to evaluate and reject the delusional belief and achieve knowledge of their motor impairments. Cognitive impairments of memory, error detection, executive function or working memory are candidate second factors that could result in this failure of belief evaluation. (shrink)

Delusions are standardly defined as attitudes that are not amenable to change in light of conflicting evidence. But what evidence do people with delusion have for and against it? Do delusions really go against their total evidence? How are the answers affected by different conceptions of evidence? -/- This chapter focuses on how delusions relate to evidence. I consider what delusions-relevant evidence people with delusions have. I give some reasons to think that people typically have evidence for their delusions, and (...) that the evidence they have against them is often overstated. I draw on this discussion to consider whether delusions are evidentially supported and epistemically rational. Finally, I discuss implications for the nature of delusion, responsibility, and treatment and suggest directions for future research. Throughout, the discussion is sensitive to different conceptions of evidence and rationality in epistemology. -/- A central upshot is that what we should say about the epistemic standing of delusions depends substantively on our positions in epistemology, in particular, on the debate between internalists and externalists about evidence. If we want clarity on the epistemic standing of delusions, we need to incorporate more sophisticated tools from epistemology. (shrink)

Anorexia nervosa involves seemingly irrational beliefs about body size and the value of thinness. Historically, researchers and clinicians have avoided referring to such beliefs as delusions, instead opting for the label ‘overvalued ideas’. I discuss the relationship between the beliefs associated with anorexia nervosa and the distinction between delusions and overvalued ideas, as it is conceived in both European and American psychiatric traditions. In doing so, I question the benefit of applying the concepts of delusion and overvalued idea to anorexia (...) nervosa and raise some issues with contemporary use of the Brown Assessment of Beliefs scale for assessing the level of delusionality associated with the disorder. (shrink)

In this paper, I argue (1) that the contents of some delusions are believed with sufficient confidence; (2) that a delusional subject could have a conscious belief in the content of his delusion (p), and concurrently judge a contradictory content (not-p) – his delusion could be transparent, and (3) that the existence of even one such case reveals a problem with pretty much all existing accounts of lying, since it suggests that one can lie by asserting what one consciously and (...) confidently believes is true, and (4) sincerity, since it suggests that asserting a proposition you believe is true is neither sufficient nor necessary for sincerity. If I am right about (1) and (2), then (3) and (4) follow easily. Therefore, the paper is mainly devoted to an analysis of transparent delusion and defending (1) and (2). (shrink)

I would like to thank Sullivan-Bissett and Noordhof for their stimulating comments on my 2023 paper in Neuroethics. In this reply, I will (1) articulate some deeper disagreements that may underpin our disagreement on the nature of delusion, (2) clarify their misrepresentation of my previous arguments as a defence of the two-factor theory in particular, and (3) finally conduct a comparison between the Maherian one-factor theory and the two-factor theory, showing that the two-factor theory is better supported by evidence.

This chapter introduces the rationalist model of delusions. It begins by presenting John Campbell’s seminal proposal that delusions are caused top-down by pathological Wittgensteinian framework or hinge beliefs. After presenting Campbell’s rationalist account of delusions, the chapter raises and examines prominent objections by Tim Bayne & Elisabeth Pacherie as well as by Tim Thornton. The former make an important distinction between the aetiological top-down cognitive part and the epistemological rationalist framework part of Campbell’s account. The thesis that delusions are caused (...) top-down by pathological beliefs is not equivalent to the thesis that delusions are Wittgensteinian framework certainties. This chapter endorses this distinction. While the arguments against the top-down aspect are found to be more convincing – which motivates popular two-factor theories – the rationalist framework model of delusions is defended as an epistemologically promising account of delusion. Finally, this chapter examines a range of developments that have been made taking Campbell’s rationalism as a starting point. Most prominently the section examines Eilan’s early development of rationalism and Rhodes and Gipps’ proposal that delusions are not framework propositions but a product of their absence. (shrink)

This chapter connects the phenomenon of double bookkeeping to two critical debates in the philosophy of delusion: one from the analytic tradition and one from the phenomenological tradition. First, I will show how the failure of action guidance on the part of some delusions suggests an argument to the standard view that delusions are beliefs (doxasticism about delusion) and how its proponents have countered it by ascribing behavioral inertia to avolition, emotional disturbances, or a failure of the surrounding environment in (...) supporting the agent’s motivation to act. Second, I will show how the mismatch between the experience of double bookkeeping and that of having the usual propositional attitudes of folk psychology suggests another, more recalcitrant argument not only against doxasticism but against the very attempt to fit delusion into folk psychology. Third, I will show how phenomenologically inspired theories of delusion, such as the multiple realities hypothesis, bypass the debates above and focus on describing and understanding the disturbances in the structure of experience undergone by patients. I conclude that the philosophical discussions ensuing from an appreciation of double bookkeeping show some of the limitations of the analytic philosophical approach to delusion. (shrink)

It is argued that in order to properly engage with the debate regarding the ethics of belief one first needs to determine the nature of the propositional attitude in question. This point is illustrated by discussing a related topic from social philosophy, broadly conceived, concerning the nature of, and inter-relationship between, delusions and the Wittgensteinian notion of a hinge commitment. Are we to understand either or both of these notions as beliefs? Are delusions a kind of hinge commitment? In answering (...) these questions we will appeal to a distinction between folk belief and knowledge-apt belief. It is argued that while both delusions and hinge commitments count as beliefs in the former sense, neither is a belief in the latter sense. Moreover, once we understand what is involved in the notion of a hinge commitment, it will also become clear why delusions are not hinge commitments. It is claimed that by gaining an understanding of delusions and hinge commitments, and thereby of two fundamental ways of thinking about belief, we will be in a better position to determine what is at issue in the ethics of belief debate. (shrink)

Delusions play an important and fascinating role in philosophy and are a particularly fertile area of study in recent years, spanning philosophy of mind and psychology, epistemology, ethics, psychology, psychiatry, and cognitive science. The Routledge Handbook of Philosophy of Delusion explores the conceptual and philosophical issues in the study of delusion and is the first major reference source of its kind. Comprising 38 chapters by an international team of contributors, the Handbook is divided into six clear parts: The Nature of (...) Delusion Delusion in Disorders Epistemology of Delusion Delusion's Place in the Mind Delusion Formation Responsibility, Culture, and Society. Within these sections key topics are discussed including delusions and wellbeing, delusions as they occur in wider mental disorder, the epistemic profile of delusions (evidence, justification, rationality), how delusions are formed, delusions and folk psychology (how they relate to belief, self-deception, imagination, and so on), and delusions in the wider social and cultural context. An outstanding resource for both students and researchers, The Routledge Handbook of Philosophy of Delusion is essential reading for those working on delusion in philosophy departments, and also suitable for those in related disciplines such as psychology, psychiatry, and cognitive science. (shrink)

Monothematic delusions are bizarre beliefs which are often accompanied by highly anomalous experiences. For philosophers and psychologists attracted to the exploration of mental phenomena in an evolutionary framework, these beliefs represent—notwithstanding their rarity—a puzzle. A natural idea concerning the biology of belief is that our beliefs, in concert with relevant desires, help us to navigate our environments, and so, in broad terms, an evolutionary story of human belief formation will likely insist on a function of truth (true beliefs tend to (...) lead to successful action). Monothematic delusions are systematically false and often harmful to the proper functioning of the agent and the navigation of their environment. So what are we to say? A compelling thought is that delusions are _malfunctioning_ beliefs. Compelling though it may be, I argue against this view on the grounds that it does not pay due attention to the circumstances in which monothematic delusions are formed, and fails to establish _doxastic_ malfunction. I argue instead that monothematic delusions are _misfunctioning_ beliefs, that is, the result of mechanisms of belief formation operating in historically abnormal conditions. Monothematic delusions may take their place alongside a host of other strange beliefs formed in difficult epistemic conditions, but for which no underlying doxastic malfunction is in play. (shrink)

Chenwei Nie ([22]) argues against a Maherian one-factor approach to explaining delusion. We argue that his objections fail. They are largely based on a mistaken understanding of the approach (as committed to the claim that anomalous experience is sufficient for delusion). Where they are not so based, they instead rest on misinterpretation of recent defences of the position, and an underestimation of the resources available to the one-factor theory.

In this paper I argue that in her new book, Why Delusions Matter, Lisa Bortolotti offers us a new way to dispel a major objection to psychedelic-assisted psychotherapy, the Comforting Delusions Objection.

INTRODUCTION: A number of prescribed medicines have been reported in cases of drug-induced delusion, such as dopaminergic agents or psychostimulants. But to this day, most studies are based on a limited number of cases and focus on a few drug classes, so a clear overview of this topic remains difficult. To address this issue, we provide in this article a comprehensive analysis of drug-induced delusion, based on the World Health Organization (WHO) pharmacovigilance database. METHODS: We performed a disproportionality analysis of (...) this database using the information component (IC). The IC compares observed and expected values to find associations between drugs and delusion, using disproportionate Bayesian reporting. An IC0.25 (lower end of the IC 95 credibility interval) \textgreater 0 is considered statistically significant. RESULTS: Here we present an analysis of 4559 suspected drug-induced delusion reports in the WHO pharmacovigilance database. These results identified 66 molecules statistically associated with delusion and an extensive analysis of confounding factors and coprescriptions was performed, using full database as background with an IC0.25 \textgreater 0. The main drug classes involved were antidepressants, antiepileptics, dopaminergic agents, opioids, antiinfective agents, benzodiazepines, anti-dementia drugs and psychostimulants. CONCLUSION: These results will help clinicians identify potential suspected drugs associated with delusion and decide which drug to discontinue and eventually lead to a re-evaluation of drug labels for some molecules. (shrink)

The aim of this paper is twofold. First, I want to re-examine the epistemic status of elaborated delusions. Bortolotti (2016, 2020) claims that they can be epistemically innocent. However, I will show that this type of delusions is more unique than suggested by the existing analyses of their epistemic status. They typically cause more profound harms than other kinds of delusions, and in most cases, it would be counterproductive to classify them as epistemically beneficial or innocent. I will employ predictive (...) and phenomenological models of delusions and the enactivist notion of sensus communis to explain the harms and possible benefits of elaborated delusions and why I think the existing definition does not fully grasp them. Based on this analysis, I will propose changes to the conditions for epistemic innocence. (shrink)

Monothematic delusions are delusions whose contents pertain to a single subject matter. Examples include Capgras delusion, the delusion that a loved one has been replaced by an impostor, and Cotard delusion, the delusion that one is dead or does not exist. Two-factor accounts of such delusions hold that they are the result of both an experiential deficit, for instance flattened affect, coupled with an aberrant cognitive response to that deficit. In this paper we develop a new expressivist two-factor account of (...) delusion. In contrast to existing endorsement and explanationist accounts, which treat delusions as either explanations or endorsements of the contents of these disordered experiences, we hold that delusional beliefs have an expressive function: they characterize, in impressionistic terms, what the subject’s experience is like for them. We show how our account improves upon existing two-factor views in explaining the central features of monothematic delusions, in particular the way in which delusional subjects fall short of the ideal of rationality. (shrink)