What kinds of mental states can be based on epistemic reasons? The standard answer is only beliefs. I argue that perceptual states can also be based on reasons, as the result of crossmodal interactions. A perceptual state from one modality can provide a reason on which an experience in another modality is based. My argument identifies key markers of the basing relation and locates them in the crossmodal Marimba Illusion (Schutz & Kubovy 2009). The subject’s auditory experience of (...) musical tone duration is based on the reason provided by her visual representation of the length of the musician’s gesture and other stored perceptual principles. (shrink)

We can discern two opposing viewpoints regarding synesthesia. According to the first, it is an oddity, an outlier, or a disordered condition. According to the second, synesthesia is pervasive, driving creativity, metaphor, or language itself. Which is it? Ultimately, I favor the first perspective, according to which cross-sensory synesthesia is an outlying condition. But the second perspective is not wholly misguided. My discussion has three lessons. First, synesthesia is just one of a variety of effects in which one sense modality (...) causally impacts and reshapes experience associated with another. These effects are utterly common. However, due to their unfamiliarity, and to their conflict with a widespread conception of the role of the senses in perception and perceptual experience, until recently they have been surprising. Second, synesthesia nevertheless must be distinguished from other inter-modal effects that lead to misperception, such as crossmodal illusions. Third, synesthesia also may be distinguished from the potentially much broader class of synesthetic effects, which could be common across the population and within individuals. (shrink)

Suppose that you are at a live jazz show. The drummer begins a solo. You see the cymbal jolt and you hear the clang. But in addition seeing the cymbal jolt and hearing the clang, you are also aware that the jolt and the clang are part of the same event. Casey O’Callaghan (forthcoming) calls this awareness “intermodal feature binding awareness.” Psychologists have long assumed that multimodal perceptions such as this one are the result of a subpersonal feature binding mechanism (...) (see Vatakis and Spence, 2007, Kubovy and Schutz, 2010, Pourtois et al., 2000, and Navarra et al., 2012). I present new evidence against this. I argue that there is no automatic feature binding mechanism that couples features like the jolt and the clang together. Instead, when you experience the jolt and the clang as part of the same event, this is the result of an associative learning process. The cymbal’s jolt and the clang are best understood as a single learned perceptual unit, rather than as automatically bound. I outline the specific learning process in perception called “unitization,” whereby we come to “chunk” the world into multimodal units. Unitization has never before been applied to multimodal cases. Yet I argue that this learning process can do the same work that intermodal binding would do, and that this issue has important philosophical implications. Specifically, whether we take multimodal cases to involve a binding mechanism or an associative process will have impact on philosophical issues from Molyneux’s question to the question of how active or passive we consider perception to be. (shrink)

Predictive processing (PP) accounts of perception are unique not merely in that they postulate a unity between perception and imagination. Rather, they are unique in claiming that perception should be conceptualised in terms of imagination and that the two involve an identity of neural implementation. This paper argues against this postulated unity, on both conceptual and empirical grounds. Conceptually, the manner in which PP theorists link perception and imagination belies an impoverished account of imagery as cloistered (...) from the external world in its intentionality, akin to a virtual reality, as well as endogenously generated. Yet this ignores a whole class of imagery whose intentionality is directed on the actual environment—projected mental imagery—and also ignores the fact that imagery may be triggered crossmodally in a bottom-up, stimulus-driven way. Empirically, claiming that imagery and perception share neural circuitry ignores relevant clinical results in this area. These evidence substantial perception/imagery neural dissociations, most notably in the case of aphantasia. Taken together, the arguments here suggest that PP theorists should substantially temper, if not outright abandon, their claim to a perception/imagination unity. (shrink)

Objective: Evidence suggests people experience an oral size illusion and commonly perceive oral size inaccurately; however, the nature of the illusion remains unclear. The objectives of the present study were to confirm the presence of an oral size illusion, determine the magnitude (amount) and direction (underestimation or overestimation) of the illusion, and determine whether immediately prior crossmodal perceptual experiences affected the magnitude and direction. Design: Participants (N = 27) orally assessed 9 sizes of stainless steel spheres (1/16 in to (...) 1/2 in) categorized as small, medium, or big, and matched them with digital and visual reference sets. Each participant completed 20 matching tasks in 3 assessments. For control assessments, 6 oral spheres were matched with reference sets of same-sized spheres. For primer-control assessments, similar to control, 6 matching tasks were preceded by cross-modal experiences of the same-sized sphere. For experimental assessments, 8 matching tasks were preceded by a cross-modal experience of a differently sized sphere. Results: For control assessments, small and medium spheres were consistently underestimated, and big spheres were consistently overestimated. For experimental assessments, magnitude and direction of the oral size illusion varied according to the size of the sphere used in the cross-modal experience. Conclusion: Results seemed to confirm an oral size illusion, but direction of the illusion depended on the size of the object. Immediately prior cross-modal experiences influenced magnitude and direction of the illusion, suggesting that aspects of oral perceptual experience are dependent upon factors outside of oral perceptual anatomy and the properties of the oral stimulus. (shrink)

Bill Seeley suggests that what follows from research into crossmodal perception for expression and emotion in the arts is that there is an emotional contour (i.e., a contour constitutive of the content of an emotion and potentially realizable across a range of media). As a response of sorts, I speculate as to what this might hold for philosophical and empirical enquiry into expression and emotion across the arts as well as into the nature of the emotions themselves.

According to the decomposition thesis, perceptual experiences resolve without remainder into their different modality-specific components. Contrary to this view, I argue that certain cases of multisensory integration give rise to experiences representing features of a novel type. Through the coordinated use of bodily awareness—understood here as encompassing both proprioception and kinaesthesis—and the exteroceptive sensory modalities, one becomes perceptually responsive to spatial features whose instances couldn’t be represented by any of the contributing modalities functioning in isolation. I develop an argument for (...) this conclusion focusing on two cases: 3D shape perception in haptic touch and experiencing an object’s egocentric location in crossmodally accessible, environmental space. (shrink)

In the case of ventriloquism, seeing the movement of the ventriloquist dummy’s mouth changes your experience of the auditory location of the vocals. Some have argued that cases like ventriloquism provide evidence for the view that at least some of the content of perception is fundamentally multimodal. In the ventriloquism case, this would mean your experience has constitutively audio-visual content (not just a conjunction of an audio content and visual content). In this paper, I argue that cases like ventriloquism (...) do not in fact warrant that conclusion. I then try to make sense of crossmodal cases without appealing to fundamentally multimodal content. (shrink)

The first part of this survey article presented a cartography of some of the more extensively studied forms of multisensory processing. In this second part, I turn to examining some of the different possible ways in which the structure of conscious perceptual experience might also be characterized as multisensory. In addition, I discuss the significance of research on multisensory processing and multisensory consciousness for philosophical debates concerning the modularity of perception, cognitive penetration, and the individuation of the senses.

We perceive in many ways. But several dubious presuppositions about the senses mask this diversity of perception. Philosophers, scientists, and engineers alike too often presuppose that the senses (vision, audition, etc.) are independent sources of information, perception being a sum of these independent contributions. We too often presuppose that we can generalize from vision to other senses. We too often presuppose that vision itself is best understood as a passive receptacle for an image thrown by a lens. In (...) this essay we illustrate how reflection on results from the cognitive sciences undermine these (and many other) traditional presuppositions. Our illustration situates the remaining essays in the volume, Perception and its Modalities, which further extend the case against various traditional presuppositions, and offer alternatives ways to understand the senses and their role in perception. While many of the essays in this volume represent competing views and draw on different fields, from conceptual analysis to engineering, most contributors believe that to understand perception properly, we need to treat as foundational the idea that the senses work together. From that agreement, new paradigms for theorizing about perception begin to emerge. (shrink)

This report highlights and explores five questions that arose from the multisensory integration workshop at the University of Toronto on May 9th and 10th, 2014: 1. What Is Multisensory Integration? 2. Do Multisensory Percepts Involve Emergent Features? 3. What Can Multisensory Processing Tell Us about Multisensory Awareness? 4. Is Language Processing a Special Kind of Multisensory Integration? 5. What Is the Purpose of Multisensory Integration?

This is an excerpt from a report on the workshop on multisensory integration at the University of Toronto, on May 9th and 10th, 2014, written by Kevin Connolly, Aaron Henry, Zoe Jenkin, and Andrew MacGregor, and available at: http://networksensoryresearch.utoronto.ca/Events_%26_Discussion.html This excerpt explores the question: Do multisensory percepts involve emergent features?

Recent research has begun to investigate sensory processing in relation to nonclinical variation in traits associated with the autism spectrum disorders (ASD). We propose that existing accounts of autistic perception can be augmented by considering a role for individual differences in top-down expectations for the precision of sensory input, related to the processing of state-dependent levels of uncertainty. We therefore examined ASD-like traits in relation to the rubber-hand illusion: an experimental paradigm that typically elicits crossmodal integration of visual, (...) tactile, and proprioceptive information in an unusual illusory context. Individuals with higher ASD-like traits showed reduced effects of the rubber-hand illusion on perceived arm position and reach-to-grasp movements, compared to individuals with lower ASD-like traits. These differences occurred despite both groups reporting the typical subjective experience of the illusion concerning visuotactile integration and ownership for the rubber hand. Together these results suggest that the integration of proprioceptive information with cues for arm position derived from the illusory context differs between individuals partly in relation to traits associated with ASD. We suggest that the observed differences in sensory integration can be best explained in terms of differing expectations regarding the precision of sensory estimates in contexts that suggest uncertainty. (shrink)

The predictive coding (PC) theory of attention identifies attention with the optimization of the precision weighting of prediction error. Here we provide some challenges for this identification. On the one hand, the precision weighting of prediction error is too broad a phenomenon to be identified with attention because such weighting plays a central role in multimodal integration. Cases of crossmodal illusions such as the rubber hand illusion and the McGurk effect involve the differential precision weighting of prediction error, yet (...) attention does not shift as one would predict. On the other hand, the precision weighting of prediction error is too narrow a phenomenon to be identified with attention, because it cannot accommodate the full range of attentional phenomena. We review criticisms that PC cannot account for volitional attention and affect-biased attention, and we propose that it may not be able to account for feature-based and intellectual attention. (shrink)

Molyneux's Question (MQ) concerns whether a newly sighted man would recognize/distinguish a sphere and a cube by vision, assuming he could previously do this by touch. We argue that (MQ) splits into questions about (a) shared representations of space in different perceptual systems, and about (b) shared ways of constructing higher dimensional spatiotemporal features from information about lower dimensional ones, most of the technical difficulty centring on (b). So understood, MQ resists any monolithic answer: everything depends on the constraints faced (...) by particular perceptual systems in extracting features of higher dimensionality from those of lower. Each individual question of this type is empirical and must be investigated separately. We present several variations on MQ based on different levels of dimensional integration—some of these are familiar, some novel adaptations of problems known elsewhere, and some completely novel. Organizing these cases in this way is useful because it unifies a set of disparate questions about intermodal transfer that have held philosophical and psychological interest, suggests a new range of questions of the same type, sheds light on similarities and differences between members of the family, and allows us to formulate a much-augmented set of principles and questions concerning the intermodal transfer of spatiotemporal organization. (shrink)

Multisensory processing encompasses all of the various ways in which the presence of information in one sensory modality can adaptively influence the processing of information in a different modality. In Part I of this survey article, I begin by presenting a cartography of some of the more extensively investigated forms of multisensory processing, with a special focus on two distinct types of multisensory integration. I briefly discuss the conditions under which these different forms of multisensory processing occur as well as (...) their important perceptual consequences and interrelations. In Part II, I then turn to examining of some of the different possible ways in which the structure of conscious perceptual experience might also be characterized as multisensory. In addition, I discuss the significance of research on multisensory processing and multisensory consciousness for philosophical attempts to individuate the senses. (shrink)

This is an excerpt from a report on the workshop on multisensory integration at the University of Toronto, on May 9th and 10th, 2014, written by Kevin Connolly, Aaron Henry, Zoe Jenkin, and Andrew MacGregor, and available at: http://networksensoryresearch.utoronto.ca/Events_%26_Discussion.html This excerpt explores the question: What is multisensory integration?

This is an excerpt from a report on the workshop on multisensory integration at the University of Toronto, on May 9th and 10th, 2014, written by Kevin Connolly, Aaron Henry, Zoe Jenkin, and Andrew MacGregor, and available at: http://networksensoryresearch.utoronto.ca/Events_%26_Discussion.html This excerpt explores the question: What can multisensory processing tell us about multisensory awareness?

In this Introduction we introduce the central themes of the Evaluative Perception volume. After identifying historical and recent contemporary work on this topic, we discuss some central questions under three headings: (1) Questions about the Existence and Nature of Evaluative Perception: Are there perceptual experiences of values? If so, what is their nature? Are experiences of values sui generis? Are values necessary for certain kinds of experience? (2) Questions about the Epistemology of Evaluative Perception: Can evaluative experiences (...) ever justify evaluative judgments? Are experiences of values necessary for certain kinds of justified evaluative judgments? (3) Questions about Value Theory and Evaluative Perception: Is the existence of evaluative experience supported or undermined by particular views in value theory? Are particular views in value theory supported or undermined by the existence of value experience? (shrink)

Many of Margaret Cavendish’s criticisms of Thomas Hobbes in the Philosophical Letters (1664) relate to the disorder and damage that she holds would result if Hobbesian pressure were the cause of visual perception. In this paper, I argue that her “two men” thought experiment in Letter IV is aimed at a different goal: to show the explanatory potency of her account. First, I connect Cavendish’s view of visual perception as “patterning” to the “two men” thought experiment in Letter (...) IV. Second, I provide a potential reply on Hobbes’s behalf that appeals to physiological differences between perceivers’ sense organs, drawing upon Hobbes’s optics in De homine. Third, I argue that such a reply would misunderstand Cavendish’s objective of showing the limited explanatory resources available in understanding visual perception as pressing when compared to her view of visual perception as patterning. (shrink)

Auditory perception is traditionally conceived as the perception of sounds — a friend’s voice, a clap of thunder, a minor chord. However, daily life also seems to present us with experiences characterized by the absence of sound — a moment of silence, a gap between thunderclaps, the hush after a musical performance. In these cases, do we positively hear silence? Or do we just fail to hear, and merely judge or infer that it is silent? This longstanding question (...) remains controversial in both the philosophy and science of perception, with prominent theories holding that sounds are the only objects of auditory experience and thus that our encounter with silence is cognitive, not perceptual. However, this debate has largely remained theoretical, without a key empirical test. Here, we introduce a novel empirical approach, presenting experimental evidence that silence can be genuinely perceived (not just cognitively inferred). We ask whether silences can ‘substitute’ for sounds in event-based auditory illusions — empirical signatures of auditory event representation in which auditory events distort perceived duration. Seven experiments introduce three new ‘silence illusions’ — the one-silence-is-more illusion, silence-based warping, and the oddball-silence illusion — each adapted from a prominent perceptual illusion previously thought to arise only from sounds. Subjects were immersed in ambient noise interrupted by silences structurally identical to the sounds in the original illusions. In all cases, silences elicited temporal distortions perfectly analogous to the illusions produced by sounds. Our results suggest that silence is truly heard, not merely inferred, introducing a general approach for studying absence perception. (shrink)

The success of the Bayesian approach to perception suggests probabilistic perceptual representations. But if perceptual representation is probabilistic, why doesn't normal conscious perception reflect the full probability distributions that the probabilistic point of view endorses? For example, neurons in MT/V5 that respond to the direction of motion are broadly tuned: a patch of cortex that is tuned to vertical motion also responds to horizontal motion, but when we see vertical motion, foveally, in good conditions, it does not look (...) at all horizontal. This article argues that the best Bayesian approach to this problem does not require probabilistic representation. (shrink)

Traditional accounts of the perception/cognition divide tend to draw it in terms of subpersonal psychological processes, processes into which the subject has no first-person insight. Whatever betides such accounts, there seems to also be some first-personally accessible difference between perception and thought. At least in normal circumstances, naïve subjects can typically tell apart their perceptual states from their cognitive or intellectual ones. What are such subjects picking up on when they do so? This paper is an inconclusive search (...) for an answer. At its end, I conclude, without joy, that we may have to simply accept the perception/cognition distinction as a primitive and inexplicable bright line within the sphere of conscious phenomena. (shrink)

Here are four examples of “seeing.” You see that something green is wriggling. You see that an iguana is in distress. You see that someone is wrongfully harming an iguana. You see that torturing animals is wrong. The first is an example of low-level perception. You visually represent color and motion. The second is an example of high-level perception. You visually represent kind properties and mental properties. The third is an example of moral perception. You have an (...) impression of moral properties. The fourth is an example of intuition. You intellectually grasp a general moral truth. Should moral perceptions be thought of as high-level perceptions or as intuitions? Most proponents of moral perception have thought of them as high-level perceptions. I give epistemological and methodological reasons for thinking that at least some are examples of what I call low-level intuitions—experiences in which we both apprehend abstract generalities and apply them to concrete particulars. (shrink)

According to a traditional view, there is no categorical difference between the phenomenology of perception and the phenomenology of imagination; the only difference is in degree (of intensity, resolution, etc.) and/or in accompanying beliefs. There is no categorical difference between what it is like to perceive a dog and what it is like to imagine a dog; the former is simply more vivid and/or is accompanied by the belief that a dog is really there. A sustained argument against this (...) traditional view is prosecuted by Sartre, who develops an alternative according to which there is a categorical difference between the two phenomenologies. This paper draws on Sartre’s work in this area to develop a similar account of perception and imagination as categorically different. (shrink)

The possibilities of unconscious perception and unconscious bias prompt parallel debates about unconscious mental content. This chapter argues that claims within these debates alleging the existence of unconscious content are made fraught by ambiguity and confusion with respect to the two central concepts they involve: consciousness and content. Borrowing conceptual resources from the debate about unconscious perception, the chapter distills the two conceptual puzzles concerning each of these notions and establishes philosophical strategies for their resolution. It then argues (...) that empirical evidence for unconscious bias falls victim to these same puzzles, but that progress can be made by adopting similar philosophical strategies. Throughout, the chapter highlights paths forward in both debates, illustrates how they serve as fruitful domains in which to study the relationship between philosophy and empirical science, and uses their combined study to further understanding of a general theory of unconscious content. (shrink)

Outside of philosophy, ‘intuition’ means something like ‘knowing without knowing how you know’. Intuition in this broad sense is an important epistemological category. I distinguish intuition from perception and perception from perceptual experience, in order to discuss the distinctive psychological and epistemological status of evaluative property attributions. Although it is doubtful that we perceptually experience many evaluative properties and also somewhat unlikely that we perceive many evaluative properties, it is highly plausible that we intuit many instances of evaluative (...) properties as such. The resulting epistemological status of evaluative property attributions is very much like it would be if we literally perceived such properties. (shrink)

[Penultimate draft] I present the perceptualist/representationalist theories of pain in broad outline and critically examine them in light of a competing view according to which awareness of pain is essentially introspective. I end the essay with a positive sketch of a naturalistic proposal according to which pain experiences are intentional but not fully representational. This proposal makes sense of locating pains in body parts as well as taking pains as subjective experiences.

The paper argues that the reconciliation of the Causal Theory of Perception with Disjunctivism requires the rejection of causal particularism – the idea that the ontology of causation is always and everywhere an ontology of particulars (e.g., events). The so-called ‘Humean Principle’ that causes must be distinct from their effects is argued to be a genuine barrier to any purported reconciliation, provided causal particularism is retained; but extensive arguments are provided for the rejection of causal particularism. It is then (...) explained how the reconciliation of the causal theory with disjunctivism can proceed on the basis of an ontology of facts. (shrink)

Our visual experience of the world is one of diverse objects and events, each with particular colors, shapes, and motions. This experience is so coherent, so immediate, and so effortless that it seems to result from a single system that lets us experience everything in our field of view. But however appealing, this belief is mistaken: there are severe limits on what can be visually experienced. -/- For example, in a display for air-traffic control it is important to track all (...) moving items. For a single item, this can be done without problem. Three or four can also be tracked, although some degree of effort may be needed. As the number is increased further, accurate tracking becomes more and more difficult—and eventually, impossible. Performance is evidently affected by a factor within the observer which enables certain kinds of perception to occur, but is limited in some way. This factor is generally referred to as attention. -/- At various times, attention has been associated with clarity of perception, intensity of perception, consciousness, selection, or the allocation of a limited “resource” enabling various operations (see Hatfield, 1998). During the past several decades, considerable progress has been achieved by focusing on the idea of selection (Broadbent, 1982). In particular, attention can be productively viewed as contingently selective processing. This can be embodied in various ways by various processes—there need not be a single quantity identified with all forms of attention, or a single site where it operates (Allport, 1993; Tsotsos, 2011). Although “paying attention” is often considered to be a unitary operation, it may simply refer to the control of one or more selective processes, ideally in a co-ordinated way. While this view has some cost in terms of conceptual simplicity, it can help make sense of a large set of phenomena. -/- This article surveys several of the major issues in our understanding of attention and how it relates to perception. It focuses on vision, since many—if not all—considerations are similar for all sensory modalities, and the level of understanding achieved in this domain is currently the most advanced. (shrink)

It has been objected recently that naïve realism is inconsistent with an empirically well-supported hypothesis that unconscious perception is possible. Because epistemological disjunctivism is plausible only in conjunction with naïve realism (for a reason I provide), the objection reaches it too. In response, I show that the unconscious perception hypothesis can be changed from a problem into an advantage of epistemological disjunctivism. I do this by suggesting that: (i) naïve realism is consistent with the hypothesis; (ii) the contrast (...) between epistemological disjunctivism and epistemic externalism explains the difference in epistemic import between conscious and unconscious perception. (shrink)

In this paper, I explore Augustine’s account of sense cognition in book 11 of De Trinitate. His discussion in this context focuses on two types of sensory state—what he calls “outer vision” and “inner vision,” respectively. His analysis of both types of state is designed to show that cognitive acts involving external and internal sense faculties are susceptible of a kind of trinitarian analysis. A common way to read De Trin. 11, is to interpret Augustine’s account of “outer” vision as (...) an analysis of sense perception and his account “inner” vision as an analysis of occurrent sensory memory and imagination. I argue against such a reading of De Trin. 11, however. Insofar as we take perception to be a phenomenally conscious mode of sensory awareness, outer vision cannot, I claim, be the equivalent of ordinary sense perception. For, on Augustine’s view, the deliverances of outer vision only reach the threshold of consciousness, when outer vision occurs in conjunction with inner vision. Hence, on my analysis, sense perception turns out to be a complex, hybrid state—one that involves both outer and inner vision. If I am right, acts of sense perception turn out not to be directly susceptible to trinitarian analysis. Even so, the account is interesting and nuanced for all that. (shrink)

Kant argued that the perceptual representations of space and time were templates for the perceived spatiotemporal ordering of objects, and common to all modalities. His idea is that these perceptual representations were specific to no modality, but prior to all—they are pre-modal, so to speak. In this paper, it is argued that active perception—purposeful interactive exploration of the environment by the senses—demands premodal representations of time and space.

Perception can’t have disjunctive content. Whereas you can think that a box is blue or red, you can’t see a box as being blue or red. Based on this fact, I develop a new problem for the ambitious predictive processing theory, on which the brain is a machine for minimizing prediction error, which approximately implements Bayesian inference. I describe a simple case of updating a disjunctive belief given perceptual experience of one of the disjuncts, in which Bayesian inference and (...) predictive coding pull in opposite directions, with the former implying that one’s confidence in the belief should increase, and the latter implying that it should decrease. Thus, predictive coding fails to approximately implement Bayesian inference across the interface between belief and perception. (shrink)

The outlines of a novel, fully naturalistic theory of perception are provided, that can explain perception of an object X by organism Z in terms of reflexive causality. On the reflexive view proposed, organism Z perceives object or property X just in case X causes Z to acquire causal dispositions reflexively directed back upon X itself. This broadly functionalist theory is potentially capable of explaining both perceptual representation and perceptual content in purely causal terms, making no use of (...) informational concepts. However, such a reflexive, naturalistic causal theory must compete with well entrenched, supposedly equally naturalistic theories of perception that are based on some concept of information, so the paper also includes some basic logical, naturalistic and explanatory criticisms of such informational views. (shrink)

When we perceive an object, we perceive the object from a perspective. As a consequence of the perspectival nature of perception, when we perceive, say, a circular coin from different angles, there is a respect in which the coin looks circular throughout, but also a respect in which the coin's appearance changes. More generally, perception of shape and size properties has both a constant aspect—an aspect that remains stable across changes in perspective—and a perspectival aspect—an aspect that changes (...) depending on one's perspective on the object. How should we account for the perspectival aspect of spatial perception? We present a framework within which to discuss the perspectival aspect of perception and put forward three desiderata that any account of the perspectival aspect of perception should satisfy. We discuss views on which the perspectival aspect of perception is analyzed in terms of constitutively mind-dependent appearance properties as well as views on which the perspectival aspect of perception is analyzed in terms of representations of mind-independent perspectival properties. (shrink)

Predictive approaches to the mind claim that perception, cognition, and action can be understood in terms of a single framework: a hierarchy of Bayesian models employing the computational strategy of predictive coding. Proponents of this view disagree, however, over the extent to which perception is direct on the predictive approach. I argue that we can resolve these disagreements by identifying three distinct notions of perceptual directness: psychological, metaphysical, and epistemological. I propose that perception is plausibly construed as (...) psychologically indirect on the predictive approach, in the sense of being constructivist or inferential. It would be wrong to conclude from this, however, that perception is therefore indirect in a metaphysical or epistemological sense on the predictive approach. In the metaphysical case, claims about the inferential properties of constructivist perceptual mechanisms are consistent with both direct and indirect solutions to the metaphysical problem of perception (e.g. naïve realism, representationalism, sense datum theory). In the epistemological case, claims about the inferential properties of constructivist perceptual mechanisms are consistent with both direct and indirect approaches to the justification of perceptual belief. In this paper, I demonstrate how proponents of the predictive approach have conflated these distinct notions of perceptual directness and indirectness, and I propose alternative strategies for developing the philosophical consequences of the approach. (shrink)

This paper responds to critical commentaries on my book, Perceiving Reality (OUP, 2012), by Laura Guerrero, Matthew MacKenzie, and Anand Vaidya. Guerrero focuses on the metaphysics of causation, and its role in the broader question of whether the ‘two truths’ framework of Buddhist philosophy can be reconciled with the claim that science provides the best account of our experienced world. MacKenzie pursues two related questions: (i) Is reflexive awareness (svasaṃvedana) identical with the subjective pole of a dual-aspect cognition or are (...) there alternative, perhaps better, ways of understanding this self-intimating character of mental states? (ii) Is perception constitutively intentional or is it representational? Vaidya argues that, in so far as Husserlian phenomenology and Buddhism differ in terms of their fundamental ontological commit- ments, they must be incompatible, thus rendering any cross-cultural philosophical project that seeks their rapprochement tenuous. One of my aims in Perceiving Reality is to show how accounts of perception informed by metaphysical realism can be problematic on both metaphysical and epistemological grounds, especially when relying on conceptions of consciousness that ignore its properly phenomenological features. (shrink)

‘How, then, she had asked herself, did one know one thing or another thing about people, sealed as they were?’ So asks Lily Briscoe in To the Lighthouse. It is this question, rather than any concern about pretence or deception, which forms the basis for the philosophical problem of other minds. Responses to this problem have tended to cluster around two solutions: either we know others’ minds through perception; or we know others’ minds through a form of inference. In (...) the first part of this paper I argue that this debate is best understood as concerning the question of whether our knowledge of others’ minds is based on perception or based on evidence. In the second part of the paper I suggest that our ordinary ways of thinking take our knowledge of others’ minds to be both non- evidential and non-perceptual. A satisfactory resolution to the philosophical problem of other minds thus requires us to take seriously the idea that we have a way of knowing about others’ minds which is both non-evidential and non-perceptual. I suggest that our knowledge of others’ minds which is based on their expressions – our expressive knowledge - may fit this bill. (shrink)

The chapter outlines an abstract theoretical framework that is currently (re-)emerging in the course of a theoretical convergence of several disciplines. In the first section, the fundamental problem of perception theory is formulated, namely, the generation, by the perceptual system, of meaningful categories from physicogeometric energy patterns. In the second section, it deals with basic intuitions and assumptions underlying what can be regarded as the current Standard Model of Perceptual Psychology and points out why this model is profoundly inadequate (...) for dealing with the fundamental problem of perception theory. In the third section, it discusses a level of analysis that promises to be fruitful for dealing, in conformity with established procedures of the natural sciences, with the problem of perceptual “meaning” and the problem of what constitutes a “perceptual object.” In the fourth section, it outlines a theoretical perspective on basic principles of the perceptual system which centers on the notions of complex data types and conceptual forms, and draws an entirely different theoretical picture of the role of the sensory input than traditional accounts. The final section focusses on the issue of material qualities and discusses, within the general theoretical framework outlined, some observations and results on the perception of certain material properties, namely, lustrous and glassy appearances. (shrink)

The experiments reported herein probe the visual cortical mechanisms that control near–far percepts in response to two-dimensional stimuli. Figural contrast is found to be a principal factor for the emergence of percepts of near versus far in pictorial stimuli, especially when stimulus duration is brief. Pictorial factors such as interposition (Experiment 1) and partial occlusion Experiments 2 and 3) may cooperate, as generally predicted by cue combination models, or compete with contrast factors in the manner predicted by the FACADE model. (...) In particular, if the geometrical conŽ guration of an image favors activation of cortical bipole grouping cells, as at the top of a T-junction, then this advantage can cooperate with the contrast of the conŽ guration to facilitate a near–far percept at a lower contrast than at an X-junction. Varying the exposure duration of the stimuli shows that the more balanced bipole competition in the X-junction case takes longer exposure times to resolve than the bipole competition in the T-junction case (Experiment 3). (shrink)

When we see an object, we also represent those parts of it that are not visible. The question is how we represent them: this is the problem of amodal perception. I will consider three possible accounts: (a) we see them, (b) we have non-perceptual beliefs about them and (c) we have immediate perceptual access to them, and point out that all of these views face both empirical and conceptual objections. I suggest and defend a fourth account, according to which (...) we represent the occluded parts of perceived objects by means of mental imagery. This conclusion could be thought of as a (weak) version of the Strawsonian dictum, according to which “imagination is a necessary ingredient of perception itself”. (shrink)

Scene Perception is the visual perception of an environment as viewed by an observer at any given time. It includes not only the perception of individual objects, but also such things as their relative locations, and expectations about what other kinds of objects might be encountered. -/- Given that scene perception is so effortless for most observers, it might be thought of as something easy to understand. However, the amount of effort required by a process often (...) bears little relation to its underlying complexity. A closer look shows that scene perception is a highly complex activity, and that any account of it must deal with several difficult issues: What exactly is a scene? What aspects of it do we represent? And what are the processes involved? Finding the answers to these questions has proven to be extraordinarily difficult. (shrink)

This paper provides an introduction to, and overview of, the Philosophy of Perception.

This chapter addresses two questions. First, if knowledge is accounted information, how are we supposed (to apply this analysis in order) to understand perceptual knowledge and knowledge by testimony? In the first part of the chapter, I articulate an answer in terms of a re-interpretation of perception and testimony as data providers rather than full-blown cases of knowledge. Second, if perception and testimony are correctly understood as data providers, how are we supposed (to apply this analysis in order) (...) to understand the semantic value of the data provided by such processes? In the second part of the chapter, I argue in favour of a constructionist hypothesis about how data may become meaningful for human cognitive agents through a process of repurposing of natural data/signals. The conclusion of the chapter is that human agents are natural-born data hackers. (shrink)

Augustine is commonly interpreted as endorsing an extramission theory of perception in De quantitate animae. A close examination of the text shows, instead, that he is committed to its rejection. I end with some remarks about what it takes for an account of perception to be an extramission theory and with a review of the strength of evidence for attributing the extramission the- ory to Augustine on the basis of his other works.

It seems plausible that visual experiences of darkness have perceptual phenomenal content that clearly differentiates them from absences of visual experiences. I argue, relying on psychological results concerning auditory attention, that the analogous claim is true about auditory experiences of silence. More specifically, I propose that experiences of silence present empty spatial directions like ‘right’ or ‘left’, and so have egocentric spatial content. Furthermore, I claim that such content is genuinely auditory and phenomenal in the sense that one can, in (...) principle, recognize that one is experiencing silence. This position is far from obvious, as the majority of theories concerning silence perception do not ascribe perceptual phenomenal content to experiences of silence. (shrink)

The difference between perception and cognition seems introspectively obvious in many cases. Perceiving and thinking have also been assigned quite different roles, in epistemology, in theories of reference and of mental content, in philosophy of psychology, and elsewhere. Yet what is the nature of the distinction? In what way, or ways, do perception and cognition differ? The paper reviews recent work on these questions. Four main respects in which perception and cognition have been held to differ are (...) discussed. First, their phenomenal character, such as the often-remarked vivacity or immediacy of perception. Second, the way in which they represent the world, e.g. the non-propositional nature of the contents, or non-discursive character of the vehicles, that have been held to characterise perceptual representation. Third, their place in cognitive architecture, i.e., roughly, in the information-flow of the mind, such as their alleged (non-)modularity. Fourth, their mind-world relations, e.g. the way in which perceptions seem to be tightly causally linked with distal or proximal stimuli. Against this background, we distinguish some main options for an account of the perception/cognition distinction, in particular concerning whether there is one, several, or no interesting and principled distinction(s) to be drawn here. (shrink)

We present a rigorous way to evaluate the visual perception of correlation in scatterplots, based on classical psychophysical methods originally developed for simple properties such as brightness. Although scatterplots are graphically complex, the quantity they convey is relatively simple. As such, it may be possible to assess the perception of correlation in a similar way. Scatterplots were each of 5.0 extent, containing 100 points with a bivariate normal distribution. Means were 0.5 of the range of the points, and (...) standard deviations 0.2 of this range. Precision was determined via an adaptive algorithm to find the just noticeable differences (jnds) in correlation, i.e., the difference between two side-by-side scatterplots that could be discriminated 75% of the time. Accuracy was measured by direct estimation, using reference scatterplots with fixed upper and lower values, with a test scatterplot adjusted so that its correlation appeared to be halfway between these. This process was recursively applied to yield several further estimates. Results of the discrimination tests show jnd(r) = k (1/b – r), where r is the Pearson correlation, and parameters 0 < k, b < 1. Integration yields a subjective estimate of correlation g(r) = ln(1 – br) / ln(1– b). The values of b found via discrimination closely match those found via direct estimation. As such, it appears that the perception of correlation in a scatterplot is completely described by two related performance curves, specified by two easily-measured parameters. (shrink)