Illusion and Hallucination

It is a common tactic, going back to the beginnings of religion and philosophy, to presume that we are enveloped in a world of untruth and illusion, thereby fueling our movement toward truth. In more modern times, Descartes demonstrates this process clearly with his Meditations. This work extends the Cartesian skeptical position by challenging the concept of illusion itself, asking those who have ever called something ‘an illusion’ to question the meaning of these assertions. This broader skepticism partially annihilates itself (...) without completely collapsing under the weight of self-contradiction. (shrink)

Tomamos como certo que os nossos sentidos nos colocam em contato com o ambiente ao nosso redor. Enquanto caminhamos em uma rua, vemos obstáculos que temos de contornar ou remover. Mesmo de costas, podemos ouvir a bicicleta que se aproxima e dar passagem. Em suma, por meio de experiências perceptivas (visuais, auditivas, olfativas etc.), ficamos conscientes de objetos ou eventos que estejam ocorrendo ao nosso redor. Além disso, com base no que percebemos, podemos formar e manter crenças acerca do ambiente (...) e, assim, adquirir conhecimento perceptivo acerca do mundo. A importância desse conhecimento acerca do que está ao nosso alcance perceptivo é inestimável para a nossa sobrevivência e a condução de nossos projetos cotidianos. Contudo, podemos querer saber (1) se de fato temos acesso ao mundo físico circundante por meio das nossas experiências perceptivas, e (2) se e como essas experiências justificam as nossas crenças acerca do que percebemos. Esses problemas são centrais para a epistemologia da percepção, embora não sejam os únicos. Nessa entrada, abordaremos esses dois problemas. (shrink)

The goal of perception is to infer the most plausible source of sensory stimulation. Unisensory perception of temporal order, however, appears to require no inference, since the order of events can be uniquely determined from the order in which sensory signals arrive. Here we demonstrate a novel perceptual illusion that casts doubt on this intuition: in three studies (N=607) the experienced event timings are determined by causality in real-time. Adult observers viewed a simple three-item sequence ACB, which is typically remembered (...) as ABC (Bechlivanidis & Lagnado, 2016), in line with principles of causality. When asked to indicate the time at which events B and C occurred, points of subjective simultaneity shifted so that the assumed cause B appeared earlier and the assumed effect C later, despite full attention and repeated viewings. This first demonstration of causality reversing perceived temporal order cannot be explained by post-perceptual distortion, lapsed attention, or saccades. (shrink)

Relationalism maintains that mind-independent objects are essential constituents of veridical perceptual experiences. According to the argument from hallucination, relationalism is undermined by perfect hallucinations, experiences that are introspectively indistinguishable from veridical perceptual experiences but lack an object. Recently, a new wave of relationalists have responded by questioning whether perfect hallucinations are possible: what seem to be perfect hallucinations may really be something else, such as illusions, veridical experiences of non-obvious objects, or experiences that are not genuinely possible. This paper argues (...) that however well new wave relationalism may handle brains in vats, drug users “seeing” pink elephants, and other extraordinary hallucinations, it struggles to accommodate mundane hallucinations, such as “hearing” your child cry out from the room down the hall when she is actually sound asleep or “feeling” vibrations on your thigh even when your phone isn't in your pocket. Mundane hallucinations are best explained as byproducts of noise in the perceptual system, and noise-induced hallucinations are resistant to the strategies that new wave relationalists deploy to explain away other hallucinations. Mundane hallucinations can thus underpin an especially powerful version of the argument from hallucination. (shrink)

Despite the recent surge in research on, and interest in, synesthesia, the mechanism underlying this condition is still unknown. Feedforward mechanisms involving overlapping receptive fields of sensory neurons as well as feedback mechanisms involving a lack of signal disinhibition have been proposed. Here I show that a broad range of studies of developmental synesthesia indicate that the mechanism underlying the phenomenon may involve reinstatement of brain activity in different sensory or cognitive streams in a way that is similar to what (...) happens during memory retrieval of semantically associated items. In the paper’s final sections I look at the relevance of synesthesia research, given the memory model, to our understanding of multisensory perception and common mapping patterns. (shrink)

Doxasticism about our awareness of normative (i.e. justifying) reasons – the view that we can recognise reasons for forming attitudes or performing actions only by means of normative judgements or beliefs – is incompatible with the following triad of claims: -/- (1) Being motivated (i.e. forming attitudes or performing actions for a motive) requires responding to and, hence, recognising a relevant reason. -/- (2) Infants are capable of being motivated. -/- (3) Infants are incapable of normative judgement or belief. -/- (...) It should be clear that (3) is true, given that infants lack the required reflective and conceptual capacities. So doxasticists have to reject either (1) or (2) (or both). But this forced choice may be understood as a dilemma for doxasticism. On the hand, doxasticists may adopt a Kantian approach and reject (2), precisely because they think that motivation presupposes the doxastic recognition of reasons, and because infants lack the capacity to doxastically recognise reasons. But this choice seems to wrongly reduce the responses of infants to mere reflexes or instinctive reactions. On the other hand, doxasticists may choose a Humean route and deny (1) by espousing a purely causal or teleological account of motivation. But this would mean detrimentally ignoring the normative nature of (some instances of) motivation. -/- One elegant way of avoiding this dilemma is to give up doxasticism and instead endorse experientialism – the view that we enjoy some experiential access to reasons, which is independent of, and perhaps more fundamental than, our capacity to form normative judgements and beliefs. In this talk, I would like to provide an argument for the existence of such a non-doxastic form of access to reasons. More specifically, I aim to defend the claim that our basic awareness of reasons is phenomenal in nature. What this means is that it forms part of our access from the inside to those of our mental episodes that provide us with access to reasons. In other words, when we introspectively attend to reason-giving mental episodes and what they are about, we have the impression of the presence of a reason for us. My defence of this experientialist alternative to doxasticism will primarily focus on perceptual reasons for first-order beliefs about the external world. (shrink)

In this paper I present an empirical solution to the puzzle of Macbeth's dagger. The puzzle of Macbeth's dagger is the question of whether, in having his fatal vision of a dagger, Macbeth sees a dagger. I answer this question by addressing a more general one: the question of whether perceptual verbs are intensional transitive verbs (ITVs). I present seven experiments, each of which tests a collection of perceptual verbs for one of the three features characteristic of ITVs. One of (...) these features is Nonexistence: the failure of sentences involving transitive verbs to entail the existence of their direct objects. The experiments reveal that with respect to all three of these features, "see" behaves much more like a paradigmatically extensional verb than an intensional one. But surprisingly, unlike "see", "perceive" behaves much more like a paradigmatically intensional verb. This shows that the category of perceptual verbs is not uniform with respect to the features of intensionality; while Macbeth does not see a dagger, he may still perceive one. (shrink)

Keith has just taken a hallucinogenic drug. A few minutes earlier, he was occupied with the beginning of H.H. Price's well-known book on perception. The combined effect of these activities is that Keith is now hallucinating a ripe tomato. This is not a de re hallucination. There is no particular tomato located elsewhere out of Keith's vision such that he is hallucinating that tomato as being before him. Keith is hallucinating a tomato without there being any particular tomato that he (...) is hallucinating. What is the representational content of Keith‟s experience? (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 article challenges the orthodox position that some smells are pleasantly fragrant and some tactile sensations are painful. It proposes that the affective components of our experiences are a kind of illusion. Under this alternative picture, experiences that seem to have positive or negative affect never actually do. Rather, the affective component is hyper-illusory, a second-order misrepresentation of the way things actually seem to us. While perceptual hyperillusions have elicited scepticism in other contexts, affective hyperillusions can withstand common critiques. Focusing (...) on the paradigmatic affective experience — pain — the article situates the hyperillusory account within the existing scientific and philosophical literature. Several theoretical advantages of positing a hyper-illusory structure to affective experiences emerge from the discussion. (shrink)

Modern physics has provided a range of motivations for holding time to be fundamentally undirected. But how does a temporally adirectional metaphysics, or ‘C-theory’ of time, fit with the time of experience? In this chapter, I look at what kind of problem human time poses for C-theories. First, I ask whether there is a ‘hard problem’ of human time: whether it is in principle impossible to have the kinds of experience we do in a temporally adirectional world. Second I consider (...) the ‘easy problem’: how specific directed aspects of our temporal experience are to be explained by C-theorists. This leads to a greater issue: is there such a thing as an experience of time direction at all to even be explained? I show how the kinds of experience we have that we typically associate with the idea of time being directed can be accommodated within a directionless picture of time. (shrink)

The starting point of this paper is Thomas Reid's anti-skepticism: our knowledge of the external world is justified. The justificatory process, in his view, starts with and relies upon one of the main faculties of the human mind: perception. Reid's theory of perception has been thoroughly studied, but there are some missing links in the explanatory chain offered by the secondary literature. In particular, I will argue that we do not have a complete picture of the mechanism of perception of (...) bodies. The present paper, relying, in part, on a particular theory in psychology – the feature integration theory of attention – will make a contribution in this regard. (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)

The debate between relationalism and representationalism in the philosophy of perception seems to have come to a standstill where opponents radically disagree on methodological principles or fundamental assumptions. According to Fish (this volume) this is because, not unlike Kuhnian scientific paradigms, the debate displays some elements of incommensurability. This diagnosis makes advancing the debate impossible. I argue that what is hindering progress is not a clash of research programmes, but a series of misunderstandings that can be avoided by disentangling the (...) different questions each theory is invested in and by making explicit the hidden assumptions at play in the debate. One such central assumption is what I call the Superficiality Constraint. This is the idea that the phenomenal character of experience is superficial with respect to introspection. I argue that we can make progress in the debate by assessing to what extent and at what cost relationalism can accommodate this constraint. (shrink)

According to the idealist, facts about phenomenal experience determine facts about the physical world. Any such view must account for illusions: cases where there is a discrepancy between the physical world and our experiences of it. In this paper, I critique some recent idealist treatments of illusions before presenting my own preferred account. I then argue that, initial impressions notwithstanding, it is actually the realist who has difficulties properly accounting for illusions.

Merleau-Ponty suggests that to perceive is to be “geared into” the world. In perceiving, we are related to a temporally structured modal space of bodily possibilities that is co-constituted by the body and the world. When we perceive, we are “geared into” this structure and responsive to it; when we misperceive, we are not. In misperceiving, we are unaware of our failure to be geared into the world, and in this respect, we lack awareness of what we are doing. In (...) explaining misperception via this lack of self-awareness, Merleau-Ponty anticipates a key feature of M. G. F. Martin's epistemic disjunctivism: the idea that perceptions and misperceptions can be indiscriminable because of a self-awareness we lack, rather than a set of positive phenomenal features that two experiences share. However, because Merleau-Ponty's account of self-awareness imposes relatively few cognitive demands, he is able to explain how adults, infants, and dogs can be self-aware in the same sense, and how they can fail to discriminate between their experiences in the same way. This provides Merleau-Ponty with the resources to answer Susanna Siegel's objection to epistemic disjunctivism on the basis of “cognitively unsophisticated hallucinators.”. (shrink)

Perception of a property (e.g. a colour, a shape, a size) can enable thought about the property, while at the same time misleading the subject as to what the property is like. This long-overlooked claim parallels a more familiar observation concerning perception-based thought about objects, namely that perception can enable a subject to think about an object while at the same time misleading her as to what the object is like. I defend the overlooked claim, and then use it to (...) generate a challenge for a standard way of thinking about the relationship between visual experience and rational belief formation. Put informally, that view holds that just as we can mislead others by saying something false, illusory experience misleads by misrepresenting how things stand in the world. I argue that we ought to abandon this view in favour of some radical alternative account of the relationship between visual experience and rational belief formation. (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)

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)

Experiences of motion and change are widely taken to have a ‘flow-like’ quality. Call this ‘temporal qualia’. Temporal qualia are commonly thought to be central to the question of whether time objectively passes: (1) passage realists take temporal passage to be necessary in order for us to have the temporal qualia we do; (2) passage antirealists typically concede that time appears to pass, as though our temporal qualia falsely represent time as passing. I reject both claims and make the case (...) that passage-talk plays no useful explanatory role with respect to temporal qualia, but rather obfuscates what the philosophical problem of temporal qualia is. I offer a ‘reductionist’ account of temporal qualia that makes no reference to the concept of passage and argue that it is well motivated by empirical studies in motion perception. (shrink)

This paper trials new experimental methods for the analysis of natural language reasoning and the development of critical ordinary language philosophy in the wake of J.L. Austin. Philosophical arguments and thought experiments are strongly shaped by default pragmatic inferences, including stereotypical inferences. Austin suggested that contextually inappropriate stereotypical inferences are at the root of some philosophical paradoxes and problems, and that these can be resolved by exposing those verbal fallacies. This paper builds on recent efforts to empirically document inappropriate stereotypical (...) inferences that may drive philosophical arguments. We demonstrate that previously employed questionnaire-based output measures do not suffice to exclude relevant confounds. We then report an experiment that combines reading time measurements with plausibility ratings. The study seeks to provide evidence of inappropriate stereotypical inferences from appearance verbs that have been suggested to lie at the root of the influential ‘argument from illusion’. Our findings support a diagnostic reconstruction of this argument. They provide the missing component for proof of concept for an experimental implementation of critical ordinary language philosophy that is in line with the ambitions of current ‘evidential’ experimental philosophy. (shrink)

Many contemporary theorists charge that naïve realists are incapable of accounting for illusions. Various sophisticated proposals have been ventured to meet this charge. Here, we take a different approach and dispute whether the naïve realist owes any distinctive account of illusion. To this end, we begin with a simple, naïve account of veridical perception. We then examine the case that this account cannot be extended to illusions. By reconstructing an explicit version of this argument, we show that it depends critically (...) on the contention that perceptual experience is diaphanous, or more minimally and precisely, that there can be no difference in phenomenal properties between two experiences without a difference in the scenes presented in those experiences. Finding no good reason to accept this claim, we develop and defend a simple, naïve account of both veridical perception and illusion, here dubbed Simple, Austere Naïve Realism. (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)

A widespread view among philosophers and scientists is that recorded sounds and assisted hearing differ fundamentally from natural sounds and direct hearing. It is commonly claimed, for example, that the sounds we hear over the phone are not sounds emitted by the voice of our interlocutor, but the sounds reproduced by the phone’s loudspeaker. According to this view, hearing distant sounds through communication and audio equipment is at best indirect and at worst illusory. In what follows, I shall reject these (...) claims and argue in favor of a transparent view of auditory media, including radio, telephone, phonograph, etc. According to this approach, the great gift of Scott de Martinville and Edison is not to have invented devices able to reproduce vanished sounds but rather to have created technological instruments literally able to store and transmit them to future and distant listeners. (shrink)

I am focusing on the following questions that were raised in the commentaries: How to (re)awaken reflexive thinking? How to understand hallucinations as voices of sanity? How to become an effective therapist? How could the pattern that connects be described? How can psychotherapy contribute to psychological well-being?

According to a certain kind of naïve or folk understanding of physical matter, everyday ‘solid’ objects are composed of a homogeneous, gap-less substance, with sharply defined boundaries, which wholly fills the space they occupy. A further claim is that our perceptual experience of the environment represents or indicates that the objects around us conform to this sort of conception of physical matter. Were this further claim correct, it would mean that the way that the world appears to us in experience (...) conflicts with the deliverances of our best current scientific theories in the following respect: perceptual experience would be intrinsically misleading concerning the structure of physical matter. I argue against this further claim. Experience in itself is not committed to, nor does it provide evidence for, any such conception of the nature of physical matter. The naïve/folk conception of matter in question cannot simply be ‘read-off’ from perceptual appearances. (shrink)

Although it has long been known that time is a cue to causation, recent work with adults has demonstrated that causality can also influence the experience of time. In causal reordering (Bechlivanidis & Lagnado, 2013, 2016) adults tend to report the causally consistent order of events, rather than the correct temporal order. However, the effect has yet to be demonstrated in children. Across four pre-registered experiments, 4- to 10-year-old children (N=813) and adults (N=178) watched a 3-object Michotte-style ‘pseudocollision’. While in (...) the canonical version of the clip object A collided with B, which then collided with object C (order: ABC), the pseudocollision involved the same spatial array of objects but featured object C moving before object B (order: ACB), with no collision between B and C. Participants were asked to judge the temporal order of events and whether object B collided with C. Across all age groups, participants were significantly more likely to judge that B collided with C in the 3-object pseudocollision than in a 2-object control clip (where clear causal direction was lacking), despite the spatiotemporal relations between B and C being identical in the two clips (Experiments 1—3). Collision judgements and temporal order judgements were not entirely consistent, with some participants—particularly in the younger age range—basing their temporal order judgements on spatial rather than temporal information (Experiment 4). We conclude that in both children and adults, rather than causal impressions being determined only by the basic spatial-temporal properties of object movement, schemata are used in a top-down manner when interpreting perceptual displays. (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)

Temporal binding occurs when people observe two events that they believe to be causally connected: They underestimate the length of the interval between those two events, when compared with their estimates of the length of intervals between events they believe to be causally unrelated. I discuss temporal binding in the context of Dennett and Kinsbourne’s (Behavioral and Brain Sciences, 15(2), 183–201, 1992) influential argument levelled at what they call ‘Cartesian Materialism’. In particular, I argue that Dennett and Kinsbourne’s argument trades (...) on a representational conception of perceptual experience, which blurs the boundary between perception and judgement, and that temporal binding can serve as a case study for developing an alternative, relational, conception of perceptual experience and of its relation to judgement. Based on research on the mechanisms underlying temporal binding, I provide an explanation of the phenomenon in which perception and judgement play clearly distinct roles. (shrink)

In this paper, I discuss aspects of Herbert Leyendecker’s 1913 doctoral dissertation, Towards the Phenomenology of Deceptions, which he defended in 1913 at the University of Munich. Leyendecker was a member of the Munich and Göttingen Phenomenological Circles. In my discussion of his largely neglected views, I explore the connection between his ideas concerning “attitudes”, e.g., of searching for, observing, counting, or working with objects, and the central topic of his text, perceptual illusions, thematized by Leyendecker as a kind of (...) perceptual “deception”. Indeed, Leyendecker argues that a change of attitude is a necessary aspect of an illusion. I argue that Leyendecker’s use of the notion of attitude in accounting for illusions is problematic; yet I also suggest that his ideas are not devoid of philosophical interest, in relation to current debates. (shrink)

Debates about modularity invariably involve a crucial premise about how visual illusions are experienced. This paper argues that these debates are wrongheaded, and that experience of illusions is orthogonal to the core issue of the modularity hypothesis: informational encapsulation.

This paper proposes a classificatory framework for disjunctivism about the phenomenology of visual perceptual experience. Disjunctivism of this sort is typically divided into positive and negative disjunctivism. This distinction successfully reflects the disagreement amongst disjunctivists regarding the explanatory status of the introspective indiscriminability of veridical perception and hallucination. However, it is unsatisfactory in two respects. First, it cannot accommodate eliminativism about the phenomenology of hallucination. Second, the class of positive disjunctivism is too coarse-grained to provide an informative overview of the (...) current dialectical landscape. Given this, I propose a classificatory framework which preserves the positive-negative distinction, but which also includes the distinction between eliminativism and non-eliminativism, as well as a distinction between two subclasses of positive disjunctivism. In describing each class in detail, I specify who takes up each position in the existing literature, and demonstrate that this classificatory framework can disambiguate some existing disjunctivist views. (shrink)

Are there illusions of duration? Certainly, many experiences of an event’s duration differ from its measure in clock duration, the measure of that event in seconds, minutes, hours, and so forth. However, I argue that an illusory duration requires more than difference from a real duration; it requires difference from a duration that is relevant to experience. It is plausible to hold that there are many kinds of real duration and reason to question the relevance of all of them. In (...) particular, the interpretation of experienced duration as illusory is typical because it is compared to clock time; the experience of duration goes wrong by being different from a clock measurement of duration. However, I argue that clock duration is not obviously relevant to evaluating the experience of duration.In response, one might hold that it is plausible to evaluate experience by clock duration because clocks more closely match reality than experiences do; on the scale of experience, clock time is no different to real duration. It is not that experienced duration is an illusion because it is merely different from clock duration; it is an illusion because it is different from real duration and we know this because of its difference from clock duration. It is like illusions of size: some object seems to be a size it is not and we know this by comparing it to an object we can otherwise accurately measure by meters.However, unlike size illusions, it is not clear what the ‘real duration’ is against which we should evaluate apparent duration. What is meant by ‘real duration’ involves either an appeal to the duration of substantial absolute time or some kind of duration in things, for example, duration which is the measure of change in some kind of process. is an irrelevant duration; few positions hold that we experience absolute time. As for, if real duration is a measure of change, then, for experienced duration to match clock duration, they must both agree on the relevant change. If there is a difference in what is treated as the real duration, then neither experience nor clocks can be treated as evaluable in terms of the other.Finally, we may have an illusory duration because there are cases of variation between experiences of the same duration. Yet, even here, we may be misled; we may not be directly comparing experiences. We compare the experienced durations through first measuring each in terms of clock duration. If there is a variability in the relationship between clock standard and some relevant standard for experience, then one expects anything accurately meeting one standard to differ from anything accurately meeting the other. The error is holding there is a stable relationship between the standards. This error is not a matter of our experience of duration, and so is not an illusion of duration. (shrink)

It is an orthodoxy in cognitive science that perception can occur unconsciously. Recently, Hakwan Lau, Megan Peters and Ian Phillips have argued that this orthodoxy may be mistaken. They argue that many purported cases of unconscious perception fail to rule out low degrees of conscious awareness while others fail to establish genuine perception. This paper presents a case of unconscious perception that avoids these problems. It also advances a general principle of ‘phenomenal coherence’ that can insulate some forms of evidence (...) for unconscious perception from the methodological critiques of Lau, Peters and Phillips. (shrink)

Dr Peter Sjöstedt-H reviews Dr Andrew R. Gallimore's book, Alien Information Theory. -/- This was published on PsyPressUK on 13 June 2019.

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)

Philosophy, scientific psychology, and common sense all distinguish perception from cognition. While there is little agreement about how the perception–cognition boundary ought to be drawn, one prominent idea is that perceptual states are dependent on a stimulus, or stimulus-dependent, in a way that cognitive states are not. This paper seeks to develop this idea in a way that can accommodate two apparent counterexamples: hallucinations, which are prima facie perceptual yet stimulus-independent; and demonstrative thoughts, which are prima facie cognitive yet stimulus-dependent. (...) The payoff is not only a specific proposal for marking the perception–cognition boundary, but also a deeper understanding of the natures of hallucination and demonstrative thought. (shrink)

A short essay for a popular audience on why afterimages are difficult to fit into any ontology.

The argument from illusion attempts to establish the bold claim that we are never perceptually aware of ordinary material objects. The argument has rightly received a great deal critical of scrutiny. But here we develop a criticism that, to our knowledge, has not hitherto been explored. We consider the canonical form of the argument as it is captured in contemporary expositions. There are two stages to our criticism. First, we show that the argument is invalid. Second, we identify premises that (...) can be used to make the argument valid. But we argue that the obvious fixes are problematic. If our arguments are successful, we show that the argument from illusion is even more difficult to defend than is commonly acknowledged. (shrink)

A central goal of philosophy of perception is to uncover the nature of sensory capacities. Ideally, we would like an account that specifies what conditions need to be met in order for an organism to count as having the capacity to sense or perceive its environment. And on the assumption that sensory states are the kinds of things that can be accurate or inaccurate, a further goal of philosophy of perception is to identify the accuracy conditions for sensory states. In (...) this paper I recommend a novel approach to these core issues, one that draws heavily on game-theoretic treatments of signaling in nature. A benefit of the approach is that it helps us to understand why biologists attribute sensory powers to such a diverse range of organisms, including plants, fungi, and algae. (shrink)

Teleological accounts of sensory normativity treat normal functioning for a species as a standard: sensory error involves departure from normal functioning for the species, i.e. sensory malfunction. Straightforward reflection on sensory trade-offs reveals that normal functioning for a species can exhibit failures of accuracy. Acknowledging these failures of accuracy is central to understanding the adaptations of a species. To make room for these errors we have to go beyond the teleological framework and invoke the notion of an ideal observer from (...) vision science. The notion of an ideal observer also sheds light on the important distinction between sensory malfunction and sensory limitation. (shrink)

I argue that we sometimes visually perceive the intentions of others. Just as we can see something as blue or as moving to the left, so too can we see someone as intending to evade detection or as aiming to traverse a physical obstacle. I consider the typical subject presented with the Heider and Simmel movie, a widely studied ‘animacy’ stimulus, and I argue that this subject mentally attributes proximal intentions to some of the objects in the movie. I further (...) argue that these attributions are unrevisable in a certain sense and that this result can be used to as part of an argument that these attributions are not post-perceptual thoughts. Finally, I suggest that if these attributions are visual experiences, and more particularly visual illusions, their unrevisability can be satisfyingly explained, by appealing to the mechanisms which underlie visual illusions more generally. (shrink)

This book explores the important yet neglected relationship between the philosophy of time and the temporal structure of perceptual experience. It examines how time structures perceptual experience and, through that structuring, the ways in which time makes perceptual experience trustworthy or erroneous. -/- Sean Power argues that our understanding of time can determine our understanding of perceptual experience in relation to perceptual structure and perceptual error. He examines the general conditions under which an experience may be sorted into different kinds (...) of error such as illusions, hallucinations, and anosognosia. Power also argues that some theories of time are better than others at giving an account of the structure and errors of perceptual experience. He makes the case that tenseless theory and eternalism more closely correspond to experience than tense theory and presentism. Finally, the book includes a discussion of the perceptual experience of space and how tenseless theory and eternalism can better support the problematic theory of naïve realism. -/- Philosophy of Time and Perceptual Experience originally illustrates how the metaphysics of time can be usefully applied to thinking about experience in general. It will appeal to those interested in the philosophy of time and debates about the trustworthiness of experience. (shrink)

This paper argues that the accuracy of perceptual experiences cannot be properly characterized by using the particular notion of content without breaking one of the three plausible assumptions. On the other hand, the general notion of content is not threatened by this problem. The first assumption is that all elements of content determine the accuracy conditions of an experience. The second states that objects needed for the accuracy of experiences are physical entities that stand in a perceptual relation to a (...) subject. According to the third assumption, common experiences do not have accuracy conditions that are impossible to satisfy. The above point is demonstrated by analysing illusions of identity in which the number of objects is represented incorrectly. In the concluding parts of the paper, I investigate how an alternative account of particular content can be developed by rejecting the first assumption. (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 good portion of the work in the ontology of color focuses on color properties, trying to figure out how they are related to more straightforwardly physical properties. Another focus is realism: are ordinary material objects such as pumpkins really colored? A third emphasis is the nature of what is referred to by the terms ‘what it’s like’ or ‘phenomenal character’, as applied to color. In contrast, this essay is exclusively about select color tokens. I will be arguing that whether (...) or not ordinary objects such as pumpkins are colored, regardless of what the true theory of color properties is, and independently of any talk of phenomenal character or what-it’s-likeness, some afterimage experiences are very hard to fit into any plausible ontology, physicalist or not. (shrink)

This dissertation explores the phenomenon of inner speech. It takes the form of an introduction, which introduces the phenomenon; three long, largely independent chapters; a conclusion; and an appendix. -/- The first chapter deliberates between two possible theories as to the nature of inner speech. One of these theories is that inner speech is a kind of actual speech, just as much as external speech is a kind of actual speech. When we engage in inner speech, we are actually speaking, (...) but we are doing so silently. The other theory holds that inner speech is a kind of imagined speech. When we produce inner speech, we are imagining performing the action of speaking. The chapter argues for the theory that inner speech is a kind of actual speech. -/- The second chapter argues against a theory which holds that inner speech is dialogic. On this theory, a subject represents different perspectives in inner speech and a dialogue can take place in the same sense in which a dialogue can take place between different individuals in external speech. The chapter borrows some important material from the philosophy of language to show that this position, though it might have some intuitive appeal, is ultimately implausible. -/- The third chapter is concerned with the question whether inner speech can be a source of knowledge of our own beliefs. It shows that the view that inner speech can be such a source is subject to an adapted version of a problem from the epistemology of testimony: roughly, what justification do we have for believing that we believe what we say in inner speech? It makes use of some material from the recent debate about cognitive phenomenology to develop a version of the view which is not subject to this problem. It then provides some initial discussion of the merits of this view. -/- The appendix takes up a more practical issue regarding inner speech. There is a theory that auditory verbal hallucinations – i.e. experiences of voice-hearing – take place when someone produces an utterance in inner speech but loses track of the fact that they have produced the utterance. Accordingly, they have an experience as of something being said and, not realising that they are the source of the experience, postulate some external cause, i.e. someone else speaking. The appendix develops an alternative account which has been suggested in the literature, at times drawing upon earlier work in the dissertation. (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)