When one visually hallucinates, the object of one’s hallucination is not before one’s eyes. On the standard view, that is because the object of hallucination does not exist, and so is not anywhere. Many different defenses of the standard view are on offer; each have problems. This paper defends the view that there is always an object of hallucination—a physical object, sometimes with spatiotemporally scattered parts.

Hallucination is a big deal in contemporary philosophy of perception. The main reason for this is that the way hallucination is treated marks an important stance in one of the most hotly contested debates in this subdiscipline: the debate between 'relationalists' and 'representationalists'. I argue that if we take hallucinations to be a form of mental imagery, then we have a very straightforward way of arguing against disjunctivism: if hallucination is a form of mental imagery and if mental imagery (...) and perception have some substantive common denominator, then a fortiori, perception and hallucination will also have a substantive common denominator. (shrink)

A natural starting point for theories of perceptual states is ordinary perception, in which a subject is successfully related to her mind-independent surroundings. Correspondingly, the simplest theory of perceptual states models all such states on perception. Typically, this simple, common-factor relational view of perceptual states has received a perfunctory dismissal on the grounds that hallucinations are nonperceptual. But I argue that the nonperceptual view of hallucinations has been accepted too quickly. I consider three observations thought to support the (...) view, and argue that all three are dealt with equally well by an alternative view, illusionism, on which hallucinations do involve perception. Since this is so, adopting a common-factor relational view of all perceptual states remains a tenable option. (shrink)

When you hallucinate an object, you are not in the normal sort of concurrent causal sensory interaction with that object. It's standardly further inferred that the hallucinated object does not actually exist. But the lack of normal concurrent causal sensory interaction does not imply that there does not exist an object that is hallucinated. It might be a past‐perceived object. In this paper, I argue that this claim holds for at least some interesting cases of hallucination. Hallucinations generated by (...) misleading cues (e.g. ‘seeing’ Kanizsa triangles), hallucinations of Charles Bonnet Syndrome patients, and dreams are experiences of past‐perceived objects. (shrink)

This chapter introduces and motivates the Null View about standard causally matching hallucinations. The Null View holds that these hallucinations fail to present any objects or sensible qualities, despite being dead ringers for perceptions of ordinary objects and their qualities. Motivation for the Null View comes from a neglected observation about perception-based thought, namely that perception can permit perception-based thought about a sensible quality even while misleading a subject about that quality. The chapter's other contribution is defensive. Most (...) reject the Null View on phenomenological or epistemic grounds. These objections to the Null View are sharpened and then undermined. (shrink)

In this paper, I argue that the indirect realists’ recourse to mental representations does not allow them to account for the possibility of hallucination, nor for the presentational character of visual experience. To account for the presentational character, I suggest a kind of intentionalism that is based on the interdependency between the perceived object and the embodied perceiver. This approach provides a positive account to the effect that genuine perception and hallucination are different kinds of states. Finally, I offer a (...) tentative suggestion as to how a hallucinatory experience may still be mistaken for a genuine perceptual experience. (shrink)

Relationalism is the view that perception is partly constituted by external objects (McDowell 1994; Campbell 2002; Martin 2004). Faced with the hallucination argument, and unsatisfied with the standard disjunctivist reply, some ‘new wave’ relationalists explain away the possibility of hallucinations as mere illusions (Alston 1999; Watzl 2010; Ali 2018; Masrour 2020). In this paper, I argue that some of these illusions (as in Chalmers 2005; Ali 2018) are perceptions of internal objects which appear as external ones. Then, in response (...) to the obvious screening-off objection, I argue for a novel reply called ‘intrameralism’: roughly, external objects are ordinarily perceived because they gain internal parts—they ‘grow into the head’. The preceding hallucinations are thus ultimately explained away as a kind of perceptual synecdoche, in which internal parts appear as their (ordinarily perceived) external wholes. The paper concludes by addressing some objections. (shrink)

Synesthesia literally means a “union of the senses” whereby two or more of the five senses that are normally experienced separately are involuntarily and automatically joined together in experience. For example, some synesthetes experience a color when they hear a sound, although many instances of synesthesia also occur entirely within the visual sense. In this paper, I first mainly engage critically with Sollberger’s view that there is reason to think that at least some synesthetic experiences can be viewed as truly (...) veridical perceptions, and not as illusions or hallucinations. Among other things, I explore the possibility that many forms of synesthesia can be understood as experiencing what I will call “second-order secondary properties,” that is, experiences of properties of objects induced by the secondary qualities of those objects. In doing so, I shed some light on why synesthesia is typically one-directional and its relation to some psychopathologies such as autism. (shrink)

Do self‐monitoring accounts, a dominant account of the positive symptoms of schizophrenia, explain auditory verbal hallucination? In this essay, I argue that the account fails to answer crucial questions any explanation of auditory verbal hallucination must address. Where the account provides a plausible answer, I make the case for an alternative explanation: auditory verbal hallucination is not the result of a failed control mechanism, namely failed self‐monitoring, but, rather, of the persistent automaticity of auditory experience of a voice. My argument (...) emphasizes the importance of careful examination of phenomenology as providing substantive constraints on causal models of the positive symptoms in schizophrenia. (shrink)

Several commentators have recently attributed conflicting accounts of the relation between veridical perceptual experience and hallucination to Husserl. Some say he is a proponent of the conjunctive view that the two kinds of experience are fundamentally the same. Others deny this and purport to find in Husserl distinct and non-overlapping accounts of their fundamental natures, thus committing him to a disjunctive view. My goal is to set the record straight. Having briefly laid out the problem under discussion and the terms (...) of the debate, I then review the proposals that have been advanced, disposing of some and marking others for further consideration. A.D. Smith’s disjunctive reading is among the latter. I discuss it at length, arguing that Smith fails to show that Husserl’s views on perceptual experience entail a form of disjunctivism. Following that critical discussion, I present a case for a conjunctive reading of Husserl’s account of perceptual experience. (shrink)

This paper sets out a novel response to the ‘screening off problem’ for naïve realism. The aim is to resist the claim (which many naïve realists accept) that the kind of experience involved in hallucinating also occurs during perception, by arguing that there are causal constraints that must be met if an hallucinatory experience is to occur that are never met in perceptual cases. Notably, given this response, it turns out that, contra current orthodoxy, naïve realists need not adopt any (...) particular view about the psychological nature of hallucinatory experience to handle the screening off problem. Consequently, room opens up for naïve realists to endorse whatever theory of hallucinatory experience seems to best capture the distinctive nature of such episodes. (shrink)

In a recent paper, Gow raised a new and interesting problem for externalist representationalism, the conclusion of which is that its proponents are unable to provide an acceptable account of the phenomenal character of colour hallucination. In contrast to Gow, we do not believe that the problem is particularly severe – indeed, that there is any problem at all. Thus our aim is to defend externalist representationalism against the problem raised by Gow. To this end, we will first reconstruct her (...) reasoning, and then show that it poses no real challenge to externalist representationalism. (shrink)

This paper is a new defense of the view that visual hallucinations lack content. The claim is that visual hallucinations are illusory not because their content is nonveridical, but rather because they seem to represent when they fail to represent anything in the first place. What accounts for the phenomenal character of visual experiences is not the content itself (content-representationalism), but rather the vehicle of content (vehicle-representationalism), that is, not the properties represented by visual experience, but rather the (...) relational properties of experience (or of the brain) of representing singular contents, namely particular instantiations of properties. I argue that the Russellian particular-involving proposition is the only appropriate model for the representational content of visual experience and hence that visual hallucinations are just like failed demonstrations. (shrink)

Michael Tye proposed a way of understanding the content of hallucinatory experiences. Somewhat independently, Mark Johnston provided us with elements to think about the content of hallucination. In this paper, their views are compared and evaluated. Both their theories present intricate combinations of conjunctivist and disjunctivist strategies to account for perceptual content. An alternative view, which develops a radically disjunctivist account, is considered and rejected. Finally, the paper raises some metaphysical difficulties that seem to threaten any conjunctivist theory and to (...) lead the debate to a dilemma: strong disjunctivists cannot explain the subjective indistinguishability between veridical and hallucinatory experiences, whereas conjunctivists cannot explain what veridical and hallucinatory experiences have in common. This dilemma is left here as an open challenge. (shrink)

Many take the possibility of hallucinations to imply that a relationalist account, according to which perceptual experiences are constituted by direct relations to ordinary mind-independent objects, is false. The common reaction among relationalists is to adopt a disjunctivist view that denies that hallucinations have the same nature as perceptual experiences. This paper proposes a non-disjunctivist response to the argument from hallucination by arguing that the alleged empirical and a priori evidence in support of the possibility of hallucinations (...) is inconclusive. A corollary upshot of the article is that whether hallucinations are possible or not is still an open empirical question. (shrink)

My primary aim in this article is to provide a philosophical account of the unity of hallucinations, which can capture both perceptual hallucinations (which are subjectively indistinguishable from perceptions) and non-perceptual hallucinations (all others). Besides, I also mean to clarify further the division of labour and the nature of the collaboration between philosophy and the cognitive sciences. Assuming that the epistemic conception of hallucinations put forward by M. G. F. Martin and others is largely on the (...) right track, I will focus on two main tasks: (a) to provide a satisfactory phenomenology of the subjective character of perceptions and perceptual hallucinations and (b) to redress the philosophers’ neglect of non-perceptual hallucinations. More specifically, I intend to apply one of the central tenets of the epistemic conception—that hallucinations can and should be positively characterised in terms of their phenomenological connections to perceptions—to non-perceptual hallucinations as well. That is, I will try to show that we can positively specify the class of non-perceptual hallucinations by reference to the distinctive ways in which we first-personally experience them and perceptions in consciousness. The task of saying more about their underlying third-personal nature may then be left to the cognitive sciences. (shrink)

In artificial intelligence (AI), responses generated by machine-learning models (most often large language models) may be unfactual information presented as a fact. For example, a chatbot might state that the Mona Lisa was painted in 1815. Such phenomenon is called AI hallucinations, seeking inspiration from human psychology, with a great difference of AI ones being connected to unjustified beliefs (that is, AI “beliefs”) rather than perceptual failures). -/- AI hallucinations may have their source in the data itself, that (...) is, the source content, or in the training procedure, i.e. the way the knowledge was encoded in the model’s parameters, so that errors in encoding and decoding textual and non-textual representations can cause hallucinations. In this paper, we will observe how such errors come to life and how they might be mitigated. For this purpose, we will analyze the usability of justification logics, to behave as a proof checker for validating the correctness of large language models’ (LLM) responses. Justification logic was developed by S. Artemov, and later on mostly by Artemov and M. Fitting, deriving its main idea from the logic of proofs (LP): knowledge and belief modalities are seen as justification terms, i.e. t:X stands for t is a (proper) justification for X. Justification logic originated from attempts to create semantics for intuitionistic logic where proofs were the most proper justifications, but in further development, justification logic could be applied to different kinds of justifications). With the recent attempts to mitigate incorrect LLM responses, we will analyze various guardrails that are currently used for LLM responses, and see how the logic of justification may provide its benefits as an AI safety layer against false data. (shrink)

I consider a new, non-disjunctive strategy for ‘relational’ or ‘naïve realist’ theories to respond to arguments from ‘perfect’ (causally matching) hallucinations. The strategy, in a nutshell, is to treat such hypothetical cases as instances of perception rather than hallucination. After clarifying the form and dialectic of such arguments, I consider three objections to the strategy. I provide answers to the first two objections but concede that the third — based on the possibility of ‘chaotic’ (uncaused) perfect hallucinations — (...) cannot obviously be dealt with by the proposed strategy. However, such ‘chaotic’ scenarios are also problematic for standard representational accounts of experience. Thus I conclude that perfect hallucinations pose no more of a threat to the relational theory than to its main representational rival. (shrink)

A common but overlooked form of explanation in psychiatry is what I label ‘empathetic explanation’. Empathetic explanations invoke empathetic variables, which, in addition to providing an explanation of the target phenomenon, also afford an empathetic understanding of it. Focusing on the case of auditory verbal hallucination (AVH), I argue that empathetic explanation fails to provide an adequate account of the phenomenon, perniciously shapes empirical research, and confuses empathetic understanding with scientific understanding. I close by providing a general condition on the (...) legitimate application of empathetic explanation. (shrink)

The purpose of this paper is to show that understanding AI hallucination requires an interdisciplinary approach that combines insights from epistemology and cognitive science to address the nature of AI-generated knowledge, with a terminological worry that concepts we often use might carry unnecessary presuppositions. Along with terminological issues, it is demonstrated that AI systems, comparable to human cognition, are susceptible to errors in judgement and reasoning, and proposes that epistemological frameworks, such as reliabilism, can be similarly applied to enhance the (...) trustworthiness of AI outputs. This exploration seeks to deepen our understanding of the possibility of AI cognition and its implications for the broader philosophical questions of knowledge and intelligence. (shrink)

Despite the recent proliferation of scientific, clinical, and narrative accounts of auditory verbal hallucinations, the phenomenology of voice hearing remains opaque and undertheorized. In this article, we outline an interdisciplinary approach to understanding hallucinatory experiences which seeks to demonstrate the value of the humanities and social sciences to advancing knowledge in clinical research and practice. We argue that an interdisciplinary approach to the phenomenology of AVH utilizes rigorous and context-appropriate methodologies to analyze a wider range of first-person accounts of (...) AVH at 3 contextual levels: cultural, social, and historical; experiential; and biographical. We go on to show that there are significant potential benefits for voice hearers, clinicians, and researchers. These include informing the development and refinement of subtypes of hallucinations within and across diagnostic categories; “front-loading” research in cognitive neuroscience; and suggesting new possibilities for therapeutic intervention. In conclusion, we argue that an interdisciplinary approach to the phenomenology of AVH can nourish the ethical core of scientific enquiry by challenging its interpretive paradigms, and offer voice hearers richer, potentially more empowering ways to make sense of their experiences. (shrink)

Against a view currently popular in the literature, it is argued that Kant was not a niıve realist about perceptual experience. Naive realism entails that perceptual experience is object-dependent in a very strong sense. In the first half of the paper, I explain what this claim amounts to and I undermine the evidence that has been marshalled in support of attributing it to Kant. In the second half of the paper, I explore in some detail Kant’s account of hallucination and (...) argue that no such account is available to someone who thinks that veridical perceptual experience is object-dependent in the naive realist sense. Kant’s theory provides for a remarkably sophisticated, bottom-up explanation of the phenomenal character of hallucinatory episodes and is crucial for gaining a proper understanding of his model of the mind and its place in nature. (shrink)

In this chapter we will explore new avenues for developing and defending Naïve Realism (also known as Relationalism), understood as a thesis about the phenomenal character of experience. The core claim of Naive Realism is that ‘what it’s like’ for a subject who enjoys a normal, successful perceptual experience of her surroundings consists in her being directly consciously aware of mind-independent entities in her external environment. It is widely agreed that the strongest challenge to Naïve Realism comes from the alleged (...) possibility of total hallucinations, and the orthodox line of response has been to adopt Disjunctivism about perceptual experience. In this chapter, we will instead focus on an emerging alternative family of responses, which we’ll call ‘New Wave Relationalism’ (NWR). The core commitment of NWR is to reject the initial assumption that there can be total hallucinations that are both non-relational and subjectively indistinguishable from genuine perceptions. The primary aim for this chapter will be to explore and defend this broad NWR strategy for responding to the threat posed by hallucinations to Naïve Realism. We will argue that which specific version or species of NWR a Naïve Realist should adopt will depend on their background methodological and metaphysical commitments. (shrink)

“Perception is controlled hallucination,” according to proponents of predictive processing accounts of vision. I say they are right that something like this is a consequence of their view but wrong in how they have pursued the idea. The focus of my counterproposal is the causal theory of perception, which I develop in terms of a productive concept of causation. Cases of what otherwise seem like successful perception are instead mere veridical hallucination if predictive processing accounts are correct, I argue, because (...) of the role played within such accounts by absences, which cannot enter into productive causal relations. -/- I offer two arguments in support of the productive theory of perception. The first is loosely Kantian, focusing on the role that receptivity and spontaneity play in perception. The second focuses on what perception and hallucination have in common. I conclude with a series of objections and replies. (shrink)

A widely held assumption is that hallucinations are not a type of perception. Coupled with the idea that hallucinations possess phenomenal character, this assumption raises a problem for naive realism, which maintains that phenomenal character is at least partly constituted by perceived worldly objects. Naive realists have typically responded by adopting a disjunctive view of phenomenal character. But in what follows, I argue that to resolve the conflict we should instead reject the idea that hallucinations are not (...) a type of perception. I argue that this idea is supported by six alleged differences between hallucination and perception, but these differences are all accommodated for in a particular type of perception, picture perception. Drawing on picture perception’s resources, I offer an account of hallucinations which construes them as a type of perception, and does so in a way that that preserves their idiosyncrasies and varieties, and in a way compatible with naive realism. (shrink)

The distinction between the body schema and the body image has become the stock in trade of much recent work in cognitive neuroscience and philosophy. Yet little is known about the interactions between these two types of body representations. We need to account not only for their dissociations in rare cases, but also for their convergence most of the time. Indeed in our everyday life the body we perceive does not conflict with the body we act with. Are the body (...) image and the body schema then somehow reshaping each other or are they relatively independent and do they only happen to be congruent? On the basis of the study of bodily hallucinations, we consider which model can best account for the body schema/body image interactions. (shrink)

One of the leading cognitive models of auditory verbal hallucinations (AVHs) proposes such experiences result from a disturbance in the process by which inner speech is attributed to the self. Research in this area has, however, proceeded in the absence of thorough cognitive and phenomenological investigations of the nature of inner speech, against which AVHs are implicitly or explicitly defined. In this paper we begin by introducing philosophical phenomenology and highlighting its relevance to AVHs, before briefly examining the evolving (...) literature on the relation between inner experiences and AVHs. We then argue for the need for philosophical phenomenology (Phenomenology) and the traditional empirical methods of psychology for studying inner experience (phenomenology) to mutually inform each other to provide a richer and more nuanced picture of both inner experience and AVHs than either could on its own. A critical examination is undertaken of the leading model of AVHs derived from phenomenological philosophy, the ipseity disturbance model. From this we suggest issues that future work in this vein will need to consider, and examine how interdisciplinary methodologies may contribute to advances in our understanding of AVHs. Detailed suggestions are made for the direction and methodology of future work into AVHs, which we suggest should be undertaken in a context where phenomenology and physiology are both necessary, but neither sufficient. (shrink)

Pautz has argued that the most prominent naive realist account of hallucination—negative epistemic disjunctivism—cannot explain how hallucinations enable us to form beliefs about perceptually presented properties. He takes this as grounds to reject both negative epistemic disjunctivism and naive realism. Our aims are two: First, to show that this objection is dialectically ineffective against naive realism, and second, to draw morals from the failure of this objection for the dispute over the nature of perceptual experience at large.

A theory of the structure and cognitive function of the human imagination that attempts to do justice to traditional intuitions about its psychological centrality is developed, largely through a detailed critique of the theory propounded by Colin McGinn. Like McGinn, I eschew the highly deflationary views of imagination, common amongst analytical philosophers, that treat it either as a conceptually incoherent notion, or as psychologically trivial. However, McGinn fails to develop his alternative account satisfactorily because (following Reid, Wittgenstein and Sartre) he (...) draws an excessively sharp, qualitative distinction between imagination and perception, and because of his flawed, empirically ungrounded conception of hallucination. His arguments in defense of these views are rebutted in detail, and the traditional, passive, Cartesian view of visual perception, upon which several of them implicitly rely, is criticized in the light of findings from recent cognitive science and neuroscience. It is also argued that the apparent intuitiveness of the passive view of visual perception is a result of mere historical contingency. An understanding of perception (informed by modern visual science) as an inherently active process enables us to unify our accounts of perception, mental imagery, dreaming, hallucination, creativity, and other aspects of imagination within a single coherent theoretical framework. (shrink)

Hallucination: Philosophy and Psychology is an edited MIT press collection that contributes to the philosophy of perception. This collection is a significant addition to the literature both for its excellent choice of texts, and its emphasis on the case of hallucinations. Dedicating a volume to hallucinatory phenomena may seem somewhat peculiar for those not entrenched in the analytic philosophy of perception, but it is easy enough to grasp their significance. Theories of perception aim to give a fundamental characterization of (...) perceptual experience, which are experiences with a sensory phenomenal character. Such perceptual experiences include cases of successfully perceiving something, but also some cases of merely seeming to perceive. This is because prima facie, some cases of seeming to perceive are more than merely thinking that one does ; they are cases of misperceiving. Hallucinations are .. (shrink)

The claim that perfect hallucination is introspectively indistinguishable from perception has been a centrepiece of philosophical theorizing about sense experience. The most common interpretation of the indistinguishability claim is modal: that it is impossible to distinguish perfect hallucination from perception through introspection alone. I run through various models of introspection and show that none of them can accommodate the modal interpretation. Rejecting the modal interpretation opens up two alternative interpretations of the indistinguishability claim. According to the generic interpretation, hallucination is (...) indistinguishable from perception despite the existence of possible exceptions, while according to the actuality interpretation, the indistinguishability of hallucination from perception consists in the actual failure to distinguish hallucination from perception. These alternative understandings of the indistinguishability claim have a number of significant implications for the problem of perception, including the rejection of perfect hallucination and illusion in favour of our ordinary, non-philosophical concepts of these states. (shrink)

Relationalism about perception minimally claims that instances of perception -- in contrast to instances of hallucination -- are constituted by the external objects perceived. Most variants of relationalism furthermore maintain that this difference in constitution is due to a difference in mental kind. One prominent example is acquaintance relationalism, which argues that perceptions are relational in virtue of acquainting us with external objects. I distinguish three variants of acquaintance relationalism -- which differ in their answers to the question of which (...) kind of awareness hallucinations involve -- and object to all of them on two main grounds. First, none of the variants can explain how hallucinations can be introspectively indistinguishable from perceptions, despite their essential difference in awareness. Second, all three variants are unable to identify the feature of hallucinations that ensure that these experiences possess the same motivational power as corresponding perceptions. Since aquaintance relationalism can satisfy neither of these two desiderata on relationalist views, it should be rejected. Hence, if we want to be relationalists about perception, we should endorse a form of relationalism that treats perceptions -- as well as hallucinations -- as representational. (shrink)

I argue that there are no plausible non-representational explanations of episodes of hallucination. To make the discussion more specific, I focus on visual hallucinations in Charles Bonnet syndrome. I claim that the character of such hallucinatory experiences cannot be explained away non-representationally, for they cannot be taken as simple failures of cognizing or as failures of contact with external reality—such failures being the only genuinely non-representational explanations of hallucinations and cognitive errors in general. I briefly introduce a recent (...) computational model of hallucination, which relies on generative models in the brain, and argue that the model is a prime example of a representational explanation referring to representational mechanisms. The notion of the representational mechanism is elucidated, and it is argued that hallucinations—and other kinds of representations—cannot be exorcised from the cognitive sciences. (shrink)

Schwartz and his team believed ChatGPT’s answers without putting in their effort to manually check. As a result, Schwartz not only had to face a court hearing and put his career on the line but also became the target of ridicule all over the Internet.

In this paper, I argue for phenomenology, Husserlian phenomenology to be precise, as providing a solid paradigm on how to determine and assess hallucination. To be more explicit, in the context of my deliberations, I analyze Susanna Schellenberg’s arguments for “phenomenal” evidence and “factive” evidence, as regards her evidential theory of perception. To pinpoint the inadequacies raised in her account of (the hallucinating) Hallie and (the veridically perceiving) Percy sharing any kind of evidence, I propose Edmund Husserl’s epistemic fulfillment as (...) a detailed epistemological analysis of perception, which takes into consideration the latter’s phenomenological complexity. (shrink)

Several theories propose that one of the core functions of inner speech (IS) is to support subjects in the completion of cognitively effortful tasks, especially those involving executive functions (EF). In this paper we focus on two populations who notoriously encounter difficulties in performing EF tasks, namely, people diagnosed with schizophrenia who experience auditory verbal hallucinations (Sz-AVH) and people within the Autism Spectrum Conditions (ASC). We focus on these two populations because they represent two different ways in which IS (...) can fail to help in EF tasks, which can be illustrative for other mental conditions. First, we review the main components of EF (Section 1). Then we explain the functions that IS is taken to perform in the domain of EF (Section 2) and review the evidence concerning problems about EF in the two populations of our study: Sz-AVH (Section 3) and ASC (Section 4). After this we further detail our account about what a properly functioning IS can do for both populations and how different IS profiles may impact EF performance: in the case of Sz-AVH, the uncontrolled and intrusive character of IS negatively affects EF performance, whereas in ASC, EF is not sufficiently supported by IS, given the tendency in this population to present a diminished use of IS (Section 5). We finally briefly discuss Attention Deficit/Hyperactivity Disorder (ADHD) and Developmental Language Disorders (DLD). (shrink)

Sensations can occur in the absence of perception and yet be experienced ‘as if’ seen, heard, tasted, or otherwise perceived. Two concepts used to investigate types of these sensory-like mental phenomena (SLMP) are mental imagery and hallucinations. Mental imagery is used as a concept for investigating those SLMP that merely resemble perception in some way. Meanwhile, the concept of hallucinations is used to investigate those SLMP that are, in some sense, compellingly like perception. This may be a difference (...) of degree. Attempts to reliably differentiate between instances of each type of SLMP remain unresolved. Despite this, the concepts of mental imagery and hallucinations are each routinely used independently of the other. These uses are especially interesting in those published accounts of experiments where equivalent findings about the neuroanatomical correlates of SLMP are reported in support of diverging knowledge-claims about the role of SLMP in neurocognitive processes. This practice presents a puzzle. To examine one aspect of this puzzle, I compare the uses of these two scientific concepts in three ways: examining their roles in differentiating between types of SLMP; exploring how their respective historical developments intersect; and analysing their contributions in neuroimaging experiments. In presenting this series of comparative analyses, I will draw on three themes from historical, philosophical, and social studies of scientific practices: interest in material contributions to knowledge; accounts of how concepts are used in experiments; and explorations of the historical conditions within which current practices emerge. Building on this literature, my comparative analyses supports five related claims. My first claim is that the concepts of mental imagery and hallucinations are each used as independent tools in neuroimaging experiments. My second claim is that, as experimental tools, the concepts of mental imagery and hallucinations are each used for investigating discrete epistemic goals. My third claim is that there are implicit interdependent associations that structure the uses of these two concepts as tools for independently investigating these discrete epistemic goals in neuroimaging experiments. This third claim rests on my analyses of both past and present uses of each concept. Firstly, as seen in their intersecting histories, there are disciplined performances of using the concepts of mental imagery and hallucinations that carry-along shared associations about the mediating role of SLMP in thought. Secondly, these interdependent ‘mediator-view’ associations continue to structure the independent uses of each concept as a tool for investigating SLMP in pursuit of specific goals. Taking this further, my fourth claim is that recognising the structured uses of the concepts of mental imagery and hallucinations can help to account for how equivalent SLMP-neuro-correlates are generated in support of diverging knowledge-claims. Finally, my fifth claim is that the structured uses of these concepts as tools can contribute to experiments in ways analogous to, yet not equivalent with, the active contributions of material instruments. Bringing these claims together, I argue that the concepts of mental imagery and hallucinations operate as structured tools that can actively contribute to the knowledge generated by neuroimaging experiments. In presenting this argument I seek to demonstrate that examining the structured uses of concepts as tools can complement existing approaches to studying how the heterogeneous dynamics of experimental practices can come to contribute to scientific knowledge in unintended ways. (shrink)

There are powerful reasons to think of perceptual content as determined at least in part by the environment of the perceiving subject. Externalist views such as this are often rejected on grounds that they do not give a good account of hallucinations. The chapter shows that this reason for rejecting content externalism is not well founded if we embrace a moderate externalism about content, that is, an externalist view on which content is only in part dependent on the experiencing (...) subject“s environment. The chapter starts by motivating content externalism. It then argues that hallucinations are best understood in terms of a deficiency of veridical perceptual experiences. The chapter discusses the consequences of this thesis by developing a view of hallucinations that is committed to externalism about content. (shrink)

We respond to Moseley and Wilkinson's defense of inner speech models of AVH.

The scientific concepts of mental imagery and hallucinations are each used independently of the other in experiments; uses that simultaneously evoke and obscure their historical connections. To highlight one of these connections, I will begin by sketching episodes from the largely separate developmental trajectories of each concept. Considering these historical sketches side-by-side, I will argue that the independent uses of these concepts each inherited a shared set of interdependent associations. In doing so, I seek to illustrate the value of (...) examining historical connections between mental imagery and hallucinations for studying the current uses of these two concepts in neuroimaging experiments. (shrink)

There are numerous studies suggesting a substantial link between psychotic hallucinatory states and some forms of disordered imaginings. We have to figure out (1) what characteristic makes imagining, not other mental states, prone to induce hallucination, and (2) what underlies the (phenomenological/conceptual) transition from imagining X to the hallucinatory experience of X? In this paper, I will try to provide answers to these questions, in order to shed light on the nature of the so-called “misidentified” or “disordered” imaginative experience. To (...) achieve this, I emphasize the phenomenological aspects of hallucination and imagination. (shrink)

My dissertation contributes to a central and ongoing debate in the philosophy of perception about the fundamental nature of perceptual states. Such states include cases like seeing, hearing, or tasting as well as cases of merely seeming to see, hear, or taste. A central question about perceptual states arises in light of misperceptual phenomena. A commonsensical view of perceptual states construes them as simply relating us to the external and mind independent objects. But some misperceptual cases suggest that these states (...) fall short of contact with the world. The result is that perceptual states are either thought to fundamentally consist in a highest common factor that falls short of perceptual contact with the world, or are thought to be disjunctive in nature, with some cases involving perceptual contact, and others receiving a different analysis. Contrary to these views, I argue that no misperceptual cases compromise perceptual contact with worldly objects, so perceptual states should be understood as relations to the external and mind-independent world. I call this view I defend Pure Relationalism, and the view of misperceptual cases that makes pure relationalism possible Illusionism. (shrink)

Hallucinations occur in a wide range of organic and psychological disorders, as well as in a small percentage of the normal population According to usual definitions in psychology and psychiatry, hallucinations are sensory experiences which present things that are not there, but are nonetheless accompanied by a powerful sense of reality. As Richard Bentall puts it, “the illusion of reality ... is the sine qua non of all hallucinatory experiences” (Bentall 1990: 82). The aim of this paper is (...) to find out what lends an experience ‘a sense of reality’: what features are required for an experience to feel ‘real’, in the relevant sense? I will investigate the claim that phenomenological features are largely responsible for a sense of reality, and will find this claim wanting. My suggestion is that a sense of reality is created and sustained by the larger nexus of the subject's beliefs. (shrink)

One central fact about hallucinations is that they may be subjectively indistinguishable from perceptions. Indeed, it has been argued that the hallucinatory experiences concerned cannot— and need not—be characterized in any more positive general terms. This epistemic conception of hallucinations has been advocated as the best choice for proponents of experiential (or “naive realist”) disjunctivism—the view that perceptions and hallucinations differ essentially in their introspectible subjective characters. In this chapter, I aim to formulate and defend an intentional (...) alternative to experiential disjunctivism called experiential intentionalism. This view not only enjoys some advantages over its rival but is also compatible with the epistemic conception of hallucinations, as well as with the disjunctivist view that perceptions and hallucinations differ essentially in their third-personal structures (e.g., their causal, informational, or reason-providing links to reality). It also maintains that there are actually two aspects to the subjective indistinguishability of mental episodes: (i) we cannot distinguish their first-personal characters in introspective awareness; and (ii) we cannot distinguish their third-personal structures in experiential awareness—that is, in how they are given to consciousness. While experiential disjunctivism makes the mistake of ignoring (ii) and reducing subjective indiscriminability to (i), experiential intentionalism correctly identifies (ii) as the primary source of the subjective indistinguishability of perception-like hallucinations. Accordingly, the intentional error involved in such hallucinations is due to the fact that we consciously experience them as possessing a relational structure. (shrink)

In this paper I explicate the notion of “presence” [Gegenwart] as it pertains to intuition. Specifically, I examine two central problems for the position that an empirical intuition is an immediate relation to an existing particular in one’s environment. The first stems from Kant’s description of the faculty of imagination, while the second stems from Kant’s discussion of hallucination. I shall suggest that Kant’s writings indicate at least one possible means of reconciling our two problems with a conception of “presence” (...) such that perceptual and hallucinatory states might be understood as different kinds of intuition. This may not be sufficient to secure the relationalist’s claim that intuition is an immediate relation to an existing particular in one’s environment, but it does show that opposition to this claim will require further argument. (shrink)

Critical discussion of Susanna Schellenberg's account of hallucination and perceptual evidence.

Austere relationism rejects the orthodox analysis of hallucinations and illusions as incorrect perceptual representations. In this article, I argue that illusions of optimal motion present a serious challenge for this view. First, I submit that austere-relationist accounts of misleading experiences cannot be adapted to account for IOMs. Second, I show that any attempt at elucidating IOMs within an austere-relationist framework undermines the claim that perceptual experiences fundamentally involve relations to mind-independent objects. Third, I develop a representationalist model of IOMs. (...) The proposed analysis combines two ideas: Evans' dynamic modes of presentation and Fine's relational semantics for identity. (shrink)