Perceptual Constancy

In general, visual experiences represent determinately. And visual experiences, generally, represent properties of distal objects like their colour, shape, and size, but they do not, generally, represent properties of proximal states like that of incoming light or the retina. By making perceptual constancies central to perceptual representation, Peter Schulte extends Karen Neander’s Causal-Informational Teleosemantic theory in order to accommodate these facts. However, by appealing to the psychophysics and chemistry of how light-related properties interact to produce stimulation to the visual system (...) and how the visual system processes such input to produce experiences, I argue that Schulte’s theory fails to accommodate the facts of distality and determinacy. (shrink)

Colour constancy is standardly defined as the visual phenomenon in which an object’s colour tends to be perceived as (approximately) constant regardless of (drastic) variations in the illumination and other viewing conditions. But a closer look at our colour experience reveals that the colour initially held to be constant varies successively and simultaneously. If colour constancy is a genuine form of perceptual constancy, then there seems to be an ambiguity involved in it that needs to be explained. In this article, (...) I explore Merleau-Ponty’s contributions to this ambiguity problem from his 1945 work, the Phenomenology of Perception. In the first part, I argue that Merleau-Ponty’s descriptions of our colour experience expose the inadequacies of two lines of response to the ambiguity problem proposed by the computational approach to colour constancy, namely the “imperfection response” and the “other-aspect response”. In the second part, I reconstruct Merleau-Ponty’s theory of colour constancy, which contains three main theses: (i) the pluralist thesis, (ii) the normative thesis, and (iii) the holistic thesis. I suggest that each of these theses provides an explanation that can do justice to the ambiguity of colour constancy. (shrink)

The ability to perceive the shapes of things as enduring through changes in how they stimulate our sense organs is vital to our sense of stability in the world. But what sort of capacity is shape constancy, and how is it reflected in perceptual experience? This paper defends a pluralist account of shape constancy: There are multiple kinds of shape constancy centered on geometrical properties at various levels of abstraction, and properties at these various levels feature in the content of (...) perceptual experience, governing patterns of apparent shape similarity. I propose that the varieties of shape constancy are subserved by the syntactic complexity of perceptual shape representations. By assigning discrete constituents to various abstract shape parameters, these representations attune us to the preservation of certain abstract shape properties through changes in more determinate shape properties. Finally, I draw broader lessons concerning the nature and function of perceptual constancy. (shrink)

Very often, objects in the scene before us are somehow perceived to be constant or uniform or unchanging in color, shape, size, or position, even while their appearance with respect to these features somehow changes. This is a familiar and pervasive fact about perception, even if it is notoriously difficult to describe accurately let alone adequately account for. These difficulties are not unrelated—how we are inclined to describ the phenomenology of perceptual constancy will affect how we are inclined to accoun (...) for it. (shrink)

Philosophical work on representation has largely focused on descriptive content, which concerns what the world is like. Neuroscientists and psychologists regularly make other sorts of content ascriptions, however, including to forward models, motor commands, and error signals. Here I focus on directive states – states that shape what a system does – in relation to the question: what makes a directive state a representation? I begin by recharacterizing Ramsey’s (2007) Job Description Challenge (JDC) so that it applies to directive states. (...) After arguing that existing answers to the JDC do not answer the “directive JDC,” I develop my own account by asking: what is the explanatory payoff of appeal to directive representations? I argue that directive representations help explain how a system achieves a particular outcome in the face of varying internal or external conditions. To be a representation, then, a directive state must make a specific causal contribution to bringing about an outcome in a way that is decouplable from any particular behavior of the system. This account captures both what is distinctive about directive representation and what it has in common with descriptive representation. It also implies that we should be much more sparing in attributing content to directive states. (shrink)

This paper presents three objections to Marco Ruffino’s account of contingent a priori truths. First, I argue that Ruffino’s “Philonous’ Objection” neglects what is widely considered the mark of perception—namely, perceptual constancies, which allow stable representations despite variable sensory input. Second, I show that Ruffino’s institutional approach to the contingent a priori faces challenges under both relational (ratio-based) and monadic (property-ascribing) interpretations of measurement statements: the former diminishes the need for stipulation, while the latter risks conflating stipulative acts with empirical (...) measurement outcomes. Third, I contend that Ruffino’s account risks an unwarranted commitment to social constructivism about brute physical facts. (shrink)

Distant things look smaller, in a sense. Why? I argue that the reason is not that our experiences have a certain subject matter, or are about certain mind-independent things and features. Instead, distant things look smaller because of our way of perceiving them. I go on to offer a hypothesis about which specific way of perceiving explains why distant things look smaller.

The sensory colors that figure in visual perceptual experience are either properties of the object of consciousness (naïve realism, sense-data theory), or properties of the subject of consciousness (adverbialism) (Section 1). I consider an argument suggested by the work of A. D. Smith that the existence of certain kinds of perceptual constancies shows that adverbialism is correct, for only adverbialism can account for such constancies (Section 3). I respond on behalf of the naïve realist that naïve realism is compatible with (...) the existence of such constancies, so long as naïve realism adopts the view that sensory colors are relational properties of physical objects, not intrinsic properties (Section 4). In other words, the naïve realist should adopt the theory of appearing (Section 5). (shrink)

We have asked what smell represents, and later we shall consider existing claims as to what vision represents, what hearing represents, and so on. Competing answers to each such question have been defended. This chapter argues that the issue of what taste represents is categorically more complicated. In particular, it raises two difficult dilemmas. The first concerns the representation of “intensity” or concentration of basic tastes such as those of salt and sweet, and what might make that representation correct or (...) incorrect. The second is based on the fact that in our gustatory experience, taste strictly so called is only one component of overall flavor, and it is in each of several ways inaccessible to introspection. So we cannot be sure that taste proper is represented by the whole person as opposed to merely figuring in an early processing stage. (shrink)

It is a common view that smell represents conditions of one’s immediate environment, such as an odor impacting the nose or the presence of a sensible quality. An apparently competing view is that, more ambitiously, smell represents distal substances and objects, such as coffee and roses and perhaps people. This chapter argues that, by the Layering thesis, we can have it both ways: often you represent an external object by representing the immediate condition. The chapter defends olfactory layering in some (...) detail, making use of Casey O’Callaghan’s family-resemblance method of distinguishing perceptual content per se from the richer belief contents produced by tacit inference. The chapter then further distinguishes smelling, seeing, hearing et al. in their ordinary senses from the outputs of the corresponding visual systems. Finally, an augmented teleosemantics is proposed. (shrink)

Some consider it obvious that vision represents. But argument is needed to show that smell does; it has never been obvious that smell represents. This chapter rebuts three reasons for doubting that smell represents, and offers several arguments that it does, based on the general idea that when we smell an object we noninferentially find out something about that object. The chapter then considers two recent proposals as to exactly what a smell represents, those of Clare Batty and Ben Young. (...) But in each case it argues (while offering a concession or two) that so far as there is a substantive disagreement, Lycan’s older proposal is preferable: that a smell represents a miasma in the air. Finally, the question is raised as to whether smell does not represent, rather, whole environmental objects and types of object; that issue is postponed until Chapter 6. (shrink)

The book has three main topics or concerns. (1) The diversity of the senses. Though all perception represents, the similarity between sense modalities ends there. The senses’ respective representational modes, styles, and structures differ very strongly from each other. (2) The Layering thesis. A single sensory representation usually has more than one content; the perceptual state represents one object or property by representing a more primitive or less ambitious one. Though this “layering” is ubiquitous, its structure and range differs dramatically (...) as between sense modalities, and in some modalities it works unexpectedly: for example, nearly all tactual representation derives from representation of conditions of or in the subject’s own skin, meaning that touch represents, e.g., the texture of a physical object by, and only by, representing stress within the skin; also the tactual layering is remarkably fine-grained and rich. (3) Aspect perception. Besides the intrinsic interest of “perceiving as”—even popular appeal, what with joke ambiguous figures such as the duck-rabbit and the old/young woman—it remains especially mysterious. Nearly all work on it has concerned vision only. But it is crucial for understanding auditory representation, which is one thing that distinguishes hearing from the other senses. Further, the auditory case greatly reinforces the idea that perceiving-as depends on expectations, it severely damages what we had thought was the best further approach to understanding aspect perception, in terms of attention. (shrink)

This chapter expounds the puzzle of “seeing as” and summarizes the philosophical state of play so long as aspect perception is considered only for the case of vision. Though ambiguous figures are the focus in popular literature, several different types of seeing-as are distinguished. Wittgenstein’s puzzle is stated: aspect-seeing is often a voluntary and thoughtful matter of interpretation; yet it is also a kind of seeing, a specifically perceptual phenomenon that is fundamental to visual phenomenology. The chapter lists 11 of (...) Wittgenstein’s further observations that have had the status of truisms. Then it states two explanatory claims that have been made as to what underlies seeing-as: Gombrich’s idea of perceptual expectations and the projecting of possibilities, and the more recent suggestion that seeing-as is a matter of attentional focus. The chapter concludes by extending the expectation-plus-attending model to smelling-as, tasting-as, and tactual feeling-as; the model continues to work reasonably well. But we shall see in the following chapter that hearing-as simply blocks the attention idea. (shrink)

This chapter considers multimodality in Casey O’Callaghan’s strict sense of that term: a perceptual representation’s object is represented neither by a single sense modality nor merely as a collection of features each of which is represented by a single modality. By definition, multimodal representation cannot be simply a case of layering. So, to explain it, we must elaborate our teleosemantics. The chapter addresses several leading cases. First, that of gustatory flavor left over from Chapter 2; flavor is constituted by contributions (...) from at least six senses and sub-senses besides taste proper. Our teleosemantics is complicated accordingly, based on the fact that biofunctions subserve more general biofunctions; a function can be subserved by multiple subsidiary and more specific functions. The same sort of analysis is then applied to further cases of multimodality: “temporal ventriloquism,” intermodal perception of causal relations as such, perceptual “capture” as in the rubber hand illusion, and multimodal proprioception. (shrink)

This chapter introduces the Layering thesis: that often a single perceptual representation has two or more intentional contents, representing one object or property by representing a more primitive or less ambitious one. The thesis is here motivated by two puzzles: Christopher Peacocke’s example of seeing trees lining a road that stretches into the distance, and the Ames chair demonstrations highlighted by Ernst Gombrich. In each case the puzzle is solved by pointing out that the visual representation at issue is in (...) one way accurate (correct, truthful) while being at the same time incorrect, a misrepresentation. In previous works Lycan had put this by saying that the visual state represents external objects by representing more primitive entities called “shapes,” but this chapter replaces the ontology of shapes with Susanna Schellenberg’s “situation-dependent properties.”. (shrink)

Among the traditional “five senses,” touch is an outlier in more than one respect. For some purposes, it comprises several different sensory systems, and it interacts almost inextricably with proprioception and kinaesthesis. After making some needed distinctions, this chapter argues that what touch primarily represents are properties internal to the skin. But tactual representation is unusually layered: by representing the skin properties, an internal tactual state further represents external objects and various of their properties, including hardness, surface texture, shape, heft, (...) vibration, comparative temperature, and such features as being wet or dry, slippery, sticky, or squishy. The chapter closes with some remarks on tactual aspect-perception (‘feeling-as’) and its lessons for aspect-perception generally. (shrink)

This chapter assumes the majority view of what hearing represents, that its objects are sounds, construed as particular worldly events constituted by wave motion in a medium. Auditory representation is layered much as vision is, but auditory aspect perception goes far beyond layering. Moreover, hearing-as plays at least two central roles in human life. One is in the appreciation of music: tonality; the ambiguity exploited in harmonic modulation; and the expressing of emotion. The other is in understanding speech: hearing sounds (...) as speech at all; disambiguating utterances; and assigning illocutionary force. Music and speech being extended temporal sequences, expectation plays a huge role in hearing-as, but attention hardly any. We learn that the attention theory, so attractive for the case of visual aspect perception, is helpless when it comes to hearing-as. Nor is teleosemantics of any use. Aspect perception is more important than had been realized, but remains unexplained. (shrink)

This chapter addresses the dispute between conservative and liberal positions on its title question. Conservatives maintain that the human visual system, specifically the system’s outputs to general cognition, represents only a narrow range of sensible qualities such as color, shape, depth, and perhaps motion; liberals suggest that the visual system represents not only ordinary physical objects such as trees, animals, and people, but causal relations, social entities, linguistic objects such as words, and more. The chapter examines a number of arguments (...) for conservative positions or for liberal positions, including Susanna Siegel’s argument from phenomenal contrast, and contends both that none succeeds and that further philosophical argument is unlikely to settle the matter. Fortunately, the Layering thesis is available: visual outputs do represent “higher-level” objects and properties, but only by representing the simpler properties and relations. The chapter goes on to discuss seeing by the use of devices such as telescopes, microscopes, television, and magnifying glasses. (shrink)

Perceptual constancy has played a significant role in philosophy of perception. It figures in debates about direct realism, color ontology, and the minimal conditions for perceptual representation. Despite this, there is no general consensus about what constancy is. I argue that an adequate account of constancy must distinguish it from three distinct phenomena: mere sensory stability through proximal change, perceptual categorization of a distal dimension, and stability through irrelevant proximal change. Standard characterizations of constancy fall short in one or more (...) of these respects. I develop an account of constancy that overcomes these problems. The account has two parts: an analysis of constancy mechanisms, and an analysis of the conditions under which a constancy capacity is exercised. I then employ this account to evaluate whether constancy is a necessary condition for perceptual representation, as some have conjectured. I argue that explanatory practice in perceptual psychology fails to support this view. Rather, it fits better with the weaker principle that representation requires specific tracking of a distal dimension. (shrink)

Higher animals need to identify and track material objects because they depend on interactions with them for nutrition, reproduction, and social interaction. This paper investigates the perception of material objects. It argues, first, that material objects are tagged, in all five external senses, as bearers of the features detected by them. This happens through a perceptual process, here entitled Generalized Completion, which creates the appearance of objects that have properties that transcend the activation of sensory receptors. The paper shows, secondly, (...) that material objects are privileged subjects for perceived motion and interaction. That is, they are perceived as subjects for these properties while their parts seem to be subjects only derivatively. Material objects are the only perceptual subjects that are both multisensory and privileged. (shrink)

I have two main goals in this paper. My first goal is to sketch a new view of color perception. The core of the view can be expressed in the following two theses: (i) the overarching function of color vision is to enable and enhance the manifestation of relevant (species-specific) competences and (ii) color experiences are correct when they result from processing that directly and non-accidentally subserves the manifestation of such competences. My second goal is to show that the view (...) can accommodate and account for a wide variety of color perceptual phenomena, including many problem cases. Importantly, the framework allows us to differentiate between two kinds of good cases of color perception: ideal cases where the demands of the relevant competences converge and non-ideal cases where the demands of the relevant competences diverge and clash. (shrink)

What is the function of color vision? In this paper, I focus on perceptual phenomena studied in psychophysics and argue that the best explanation for these phenomena is that the color visual system is a perceptual enhancement system. I first introduce two rival conceptions of the function of color vision: that color vision aims to detect or track the fine-grained colors of distal objects and scenes (Seeing Color) and that it aims to help organisms discriminate, detect, track and/or recognize ecologically (...) important objects, properties, and relations more directly (Seeing with Color). I then discuss two kinds of systematic perceptual phenomena investigated by psychophysicists: approximate color constancy and color induction. I argue from the premise that Seeing with Color better accommodates and explains these phenomena to the conclusion that it is the conception that an empirically-guided philosopher of color ought to adopt. (shrink)

The mainstream view in contemporary analytic philosophy is that perception is primarily in the business of representing the mind-independent world as it is. My dissertation explores an alternative conception: that the goal of perception is to guide successful action and that perceptions do not need to track mind-independent properties to play this action-guiding role. I focus on two types of perception: color perception and pain perception. I start with the former and advocate a pragmatist, empirically-guided approach which begins by inquiring (...) into the function of color vision. After arguing that none of the extant philosophical views of color are satisfactory, I answer the function question by focusing on systematic color perceptual phenomena investigated by psychophysicists. I argue that the human color visual system is an enhancement system: that is, its job is to help us better discriminate, track, and recognize meaningful objects, properties, and relations. I then build on this idea using the notion of ‘competence-embeddedness.’ I propose that color vision is embedded in a network of competences: the aim of color vision is to help organisms manifest these competences, and color experiences are correct when they result from competence-enhancing processing. The framework is explanatorily robust. For example, it allows me to conceptualize many textbook color illusions as special cases of successful color perception where the demands of the relevant competences clash. Finally, I use the notion of ‘competence-embeddedness’ to develop a new account of pain. I argue that the pain system is not a bodily disturbance detector, but a sophisticated, context-responsive security system whose primary goal is to help organisms manifest important behavioral and cognitive competences. (shrink)

The world shows some degree of invariance, and we perceive this invariance despite a lot of variation generated locally by our movements, changes in illumination, and the way in which our sense organs react to stimulation. Generally, philosophy and psychology each explain our perception of invariance through the notion of ‘perceptual constancy’. According to the traditional definition, perceptual constancies are capacities to perceive the objective (i.e., perceiver- and context-independent) local properties of external objects despite variation in the stimulation of sensory (...) organs. In this paper, we argue that the traditional understanding of perceptual constancy should be expanded to include a broader range of phenomena connected to the perception of invariance. Our argument starts from an odd activity: pole balancing. Balancing a pole-shaped object (e.g., a broomstick) on the palm of your hand in order to maintain it in an upright position requires (multimodal) perception and continuous tracking (within a certain range) of a particular kind of global invariant feature in the world. By examining this activity and its connection to the notion of perceptual constancy as it is traditionally understood, we propose an alternative account with the goal of clarifying the relationship between the alleged mechanisms underlying constancy and the philosophical implications of the phenomenon. (shrink)

Abstract:The notions "retinal images" and "retinal projection" are ubiquitous in both the scientific and philosophical literature on perception. However, this article argues that they belong to the former and should be kept out of the latter. In the context of the empirical investigation of perception, projections play a crucial role, and help articulate pressing research problems. But, as part of the phenomenological and conceptual analysis of perception, projections give rise to untenable models and to avoidable conundrums, such as the much (...) discussed issue of perceptual constancy. Why are projections and retinal images so prevalent in the philosophical literature? The author conjectures that the reason has to do with conceptual fallouts of the effort to give a geometric representation to changes of perspective, a mission more daunting than it initially appears to be, and one that leads to the problematic insertion of projections into phenomenology. He suggests that correcting this shows perceptual constancy to be a starting point rather than a challenge for phenomenology. (shrink)

Several studies have shown the presence of large anisotropies for tactile distance perception across several parts of the body. The tactile distance between two touches on the dorsum of the hand is perceived as larger when they are oriented mediolaterally (across the hand) than proximodistally (along the hand). This effect can be partially explained by the characteristics of primary somatosensory cortex representations. However, this phenomenon is significantly attenuated relative to differences in acuity and cortical magnification, suggesting a process of tactile (...) size constancy. It is unknown whether the same kind of compensation also takes place when estimating the size of a continuous object. Here, we investigate whether the tactile anisotropy that typically emerges when participants have to estimate the distance between two touches is also present when a continuous object touches the skin and participants have to estimate its size. In separate blocks, participants judged which of two tactile distances or objects on the dorsum of their hand felt larger. One stimulation (first or second) was aligned with the proximodistal axis (along the hand) and the other with the mediolateral axis (across the hand). Results showed a clear anisotropy for distances between two distinct points, with across distances consistently perceived as larger than along distances, as in previous studies. Critically, however, this bias was significantly reduced or absent for judgments of the length of continuous objects. These results suggest that a tactile size constancy process is more effective when the tactile size of an object has to be approximated compared to when the distance between two touches has to be determined. The possible mechanism subserving these results is described and discussed. We suggest that a lateral inhibition mechanism, when an object touches the skin, provides information through the distribution of the inhibitory subfields of the RF about the shape of the tactile RF itself. Such a process allows an effective tactile size compensatory mechanism where a good match between the physical and perceptual dimensions of the object is achieved. (shrink)

Do the physical facts of the viewed environment account for the ordinary experiences we have of that environment? According to standard philosophical views, distal facts do account for our experiences, a phenomenon explained by appeal to perceptual constancy, the phenomenal stability of objects and environmental properties notwithstanding physical changes in proximal stimulation. This essay reviews a significant but neglected research tradition in experimental psychology according to which percepts systematically do not correspond to mind-independent distal facts. Instead, stability of percept values (...) comes in degrees, and physical facts about the viewed environment alone do not account for our ordinary experiences of the world. I conclude that more attention to descriptive research in psychophysics is warranted if what is sought is a philosophical theory of the nature of our perceptual relation with the world. (shrink)

This paper resolves a paradox concerning colour constancy. On the one hand, our intuitive, pre-theoretical concept holds that colour constancy involves invariance in the perceived colours of surfaces under changes in illumination. On the other, there is a robust scientific consensus that colour constancy can persist in cerebral achromatopsia, a profound impairment in the ability to perceive colours. The first stage of the solution advocates pluralism about our colour constancy capacities. The second details the close relationship between colour constancy and (...) contrast. The third argues that achromatopsics retain a basic type of colour constancy associated with invariants in contrast processing. The fourth suggests that one person-level, conscious upshot of such processing is the visual awareness of chromatic contrasts ‘at’ the edges of surfaces, implicating the ‘colour for form’ perceptual function. This primitive type of constancy sheds new light on our most basic perceptual capacities, which mark the lower borders of representational mind. (shrink)

I argue for the following claims: (1) A core Husserlian account of perceptual constancy needs to be given in terms of indicative future-oriented conditionals but can be complemented by a counterfactual account; (2) thus conceived, constancy is a necessary aspect of content. I speak about a “core Husserlian” account so as to capture certain ideas that Michael Madary has presented as the core of Edmund Husserl's approach to perceptual constancy, viz., that “perception is partly constituted by the continuous interplay of (...) intention and fulfilment” and that this “gives us a way to understand the relationship between different appearances of the same object” (See Madary, M. (2012) “Husserl on Perceptual Constancy.” European Journal of Philosophy 20(1): 145–165.). I take myself to be developing, and perhaps correcting, Madary's view as I discuss the role of the core Husserlian ideas, and counterfactuals, in accounting for shape and color constancy, respectively. I bridge constancy and fulfilment-conditional content by appealing to the Husserlian notion of constitution, which captures the process in which objectivity and, correlatively, intentional experience, are built up in the experiential flow. (shrink)

Can young children such as 3-year-olds represent the world objectively? Some prominent developmental psychologists—such as Perner and Tomasello—assume so. I argue that this view is susceptible to a prima facie powerful objection: To represent objectively, one must be able to represent not only features of the entities represented but also features of objectification itself, which 3-year-olds cannot do yet. Drawing on Burge's work on perceptual constancy, I provide a response to this objection and motivate a distinction between three different kinds (...) of objectivity. This distinction helps advance current research on both objectivity and teleological action explanations in young children. (shrink)

Perceptual constancies have been studied by psychologists for decades, but in recent years, they have also become a major topic in the philosophy of mind. One reason for this surge of interest is Tyler Burge’s (2010) influential claim that constancy mechanisms mark the difference between perception and mere sensitivity, and thereby also the difference between organisms with genuine representational capacities and ‘mindless’ beings. Burge’s claim has been the subject of intense debate. It is becoming increasingly clear, however, that we cannot (...) hope to settle this debate (as well as related debates in the philosophy of mind) without a clear and substantive theoretical account of what perceptual constancies are. In the first part of this paper, I argue that the standard definitions in the literature fall short of providing such an account. Still, as I aim to show in the second part of the paper, by taking a closer look at some of the paradigm examples, it is possible to construct a plausible general account of perceptual constancies that is both clear and substantive, and that can serve as a firm foundation for settling debates like the dispute about Burge’s ‘constancy mechanism criterion’ for perception. (shrink)

Sensory perceptions represent things in the outside world. This mundane fact raises a major problem for naturalistic theories of content: the ‘distality problem’. In a previous paper for this journal, I presented a solution to this problem which makes central appeal to constancy mechanisms. Justin Garson, also in this journal, recently criticized my solution and suggested a Dretskean alternative to it. Here, I defend my proposal by arguing, first, that Garson's criticisms ultimately miss the mark, and secondly, that his Dretskean (...) alternative is not viable, because it faces two fundamental problems: the empirical problem and the problem of changing response functions. (shrink)

One of the central tasks for naturalistic theories of representation is to say what it takes for something to be a representation, and some leading theories have been criticised for being too liberal. Prominent discussions of this problem have proposed a producer-oriented solution; it is argued that representations must be produced by systems employing perceptual constancy mechanisms. However, representations may be produced by simple transducers if they are consumed in the right way. It is characteristic of representations to be consumed (...) by systems which are capable of independent action. This paper defends this claim; discusses more precise, naturalistic formulations; and shows how it can illuminate the explanatory payoffs which science achieves by appealing to representation. (shrink)

Arguably the most foundational principle in perception research is that our experience of the world goes beyond the retinal image; we perceive the distal environment itself, not the proximal stimulation it causes. Shape may be the paradigm case of such “unconscious inference”: When a coin is rotated in depth, we infer the circular object it truly is, discarding the perspectival ellipse projected on our eyes. But is this really the fate of such perspectival shapes? Or does a tilted coin retain (...) an elliptical appearance even when we know it’s circular? This question has generated heated debate from Locke and Hume to the present; but whereas extant arguments rely primarily on introspection, this problem is also open to empirical test. If tilted coins bear a representational similarity to elliptical objects, then a circular coin should, when rotated, impair search for a distal ellipse. Here, nine experiments demonstrate that this is so, suggesting that perspectival shapes persist in the mind far longer than traditionally assumed. Subjects saw search arrays of three-dimensional “coins,” and simply had to locate a distally elliptical coin. Surprisingly, rotated circular coins slowed search for elliptical targets, even when subjects clearly knew the rotated coins were circular. This pattern arose with static and dynamic cues, couldn’t be explained by strategic responding or unfamiliarity, generalized across shape classes, and occurred even with sustained viewing. Finally, these effects extended beyond artificial displays to real-world objects viewed in naturalistic, full-cue conditions. We conclude that objects have a remarkably persistent dual character: their objective shape “out there,” and their perspectival shape “from here.”. (shrink)

There is variation in how people perceive colors and other secondary qualities. The challenge of perceptual variation is to say whose perceptions are accurate. According to Sextus, Protagoras’ response is that all of our perceptions might be accurate. As this response is traditionally developed, it is difficult to explain color illusion and color constancy. This difficulty is due to a widespread assumption called perceptual atomism. This chapter argues that, if we want to develop Protagoras’ response, we need to give up (...) perceptual atomism. It ends with a brief sketch of an alternative called perceptual structuralism. (shrink)

Perceptual constancy, often defined as the perception of stable features under changing conditions, goes hand in hand with variation in how things look. A white wall in the orange afternoon sun still looks white, though its whiteness looks different compared with the same wall in the noon sun. Historically, this variation has often been explained in terms of our experience of “merely sensory” or subjective properties – an approach at odds with the fact that the variation does track objective features (...) of the perceptual situation, such as illumination. One approach, becoming more common, is to account for the variation in terms of further “dimensions” to perceptual experience. Especially in colour perception, this is a natural thought to have but the idea is often left vague. In this paper I argue that the “dimensional” strategy has problems of its own, but is useful in drawing out some interesting complications in the way perceptual experience is structured. Specifically, the structure of “constancy spaces” brings out the different ways in which there is stability and instability in the experience of constancy, without the need for novel or merely subjective features. Instability arises in a contingent structural feature of perceptual experience. (shrink)

Naïve realism is often characterized, by its proponents and detractors alike, as the view that for a subject to undergo a perceptual experience is for her to stand in a simple two-place acquaintance relation toward an object. However, two of the leading defenders of naïve realism, John Campbell and Bill Brewer, have thought it necessary to complicate this picture, claiming that a third relatum is needed to account for various possible differences between distinct visual experiences of the same object. This, (...) I argue, is a mistake. Once it is acknowledged that a subject’s visual experience acquaints her with more than just a single object, all of the relevant facts can be explained from within the simpler naïve realist framework. (shrink)

In this journal, Schulte develops a novel solution to the problem of distal content: by virtue of what is a mental representation about a distal object rather than a more proximal cause of that representation? Schulte maintains that in order for a representation to have a distal content, it must be produced by a constancy mechanism, along with two other conditions. I raise three objections to his solution. First, a core component of Schulte's solution is just a restrictive version of (...) Dretske's solution, but Schulte gives no argument for his restriction. Second, his proposed solution to a disjunction problem is ad hoc. Finally, his ‘far-out’ version of the distality problem is not a version of the distality problem at all. I conclude that Dretske's solution is preferable to Schulte's. (shrink)

How does perceptual experience disclose the world to our view? In the first introductory section, I set up a contrast between the representational and the purely relational conception of perceptual experience. In the second section, I discuss an argument given by Charles Travis against perceptual content. The third section is devoted to the phenomenon of perceptual constancy: in 3.1 I describe the phenomenon. In 3.2 I argue that the description given suggests a phenomenological distinction that can be deployed for a (...) defence of content. In 3.3 I compare and contrast my view of perceptual content with that of Susanna Schellenberg : 55–84, 2008). Finally, I support my conception of content by means of an argument that links content to the way in which the mind-independent nature of material objects is manifest in perceptual experience. (shrink)

Objects are central to perception and our interactions with the world. We perceive the world as parsed into discrete entities that instantiate particular properties, and these items capture our attention and shape how we interact with the environment. Recently there has been some debate about whether the sense of smell allows us to perceive odours as discrete objects, with some suggesting that olfaction is aspatial and doesn’t allow for object-individuation. This paper offers two empirically tractable criteria for assessing whether particular (...) objects are exhibited in perceptual experience— susceptibility to figure-ground segregation and perceptual constancies—and argues that these criteria are fulfilled by olfactory perception, and thus there are olfactory objects. I argue that there are, in fact, two different ways that olfaction allows for figure-ground segregation. First, I look at various Gestalt grouping principles, which are thought to govern when features are perceived as grouped into structured wholes, segregated from everything around them. I argue that these principles apply to olfactory experience, providing evidence of non-spatial figure-ground segregation. Second, I defend the contentious idea that a spatial variety of figure-ground segregation can also occur in olfaction. To see this, however, we need to look to empirical evidence showing that tactile stimulation and bodily movements play a crucial role in olfactory phenomenology. Finally, I draw on empirical evidence and olfactory phenomenology to argue that there are perceptual constancies in olfactory experience, allowing us to perceive odours as coherent objects that survive shifts in our perspectives on the world. (shrink)

This paper proposes a novel experimental approach that would help to determine whether perspectival shapes, such as the elliptical profile of a tilted plate or coin, are part of perceptual experience. If they are part of perceptual experience, then it should be possible to identify these shapes simply by attending appropriately to them. Otherwise, in order to identify perspectival shapes they must first be constructed in the visual imagination. We propose that these accounts of perspectival identification can be tested by (...) measuring the interference between visual and verbal working memory load, respectively, and the identification of perspectival shapes in the appearance of a 3D object. (shrink)

Plant predictive processing suggests that plants anticipatorily perceive their environment. This hypothesis runs up against a challenge which takes the form of two constraints on per- ception advanced by Tyler Burge: the veridicality constraint and the constancy constraint. This paper argues that the veridicality constraint can be satisfied by assuming a general account of predictive processing. To show how the constancy constraint may be fulfilled, an ecologically informed account of invariant pick-up is developed and given a place within plant predictive (...) processing. It is concluded that, against our anthro- pocentric folk-psychological notions of perception, there is reason to believe that plants engage in minimal perception. (shrink)

Properties like shape, size, and colour exhibit perceptual constancy: they appear to remain constant throughout variations in the conditions under which they are perceived. A number of writers have suggested that “apparent properties”, mind-independent relational properties that vary with the perceptual conditions, play an essential role in explaining perceptual constancy. On this view, when we see, e.g. a penny from an oblique angle, we see the circularity of the penny _by_ or _in virtue of_ seeing a mind-independent relational apparent property (...) (its elliptical look). This chapter argues that views which explain the perception of constant properties of objects by appealing to perception of mind-independent apparent properties are structurally similar to sense-datum theories of perception; as such, they face many of the same challenges. It concludes that apparent properties play at best a modest explanatory role, functioning as the objects of awareness when we direct our attention in the appropriate ways. (shrink)

This chapter explores the broad thesis that most if not all perceptual experiences are infused or soaked with imaginings. To begin, the author articulates a sense of imagination useful for this discussion, avoids some pitfalls, and incorporates the result into a schematic guidance principle. The thought behind the principle is that imaginative contributions to perceptual experiences are self-generated ingredients to perception that have a reasonably direct, ampliative impact on the relevant perceptual experiences. This framework is then applied to three sets (...) of case studies: object-kind and object-sameness experiences (Strawson 1970); colour (Macpherson 2012); and amodal completion (Nanay 2010) and perceptual constancy. Although the case studies have interesting differences, they all conform to the guidance principle. Since each has the potential to independently justify the thesis that perceptual experiences are infused with imaginings, they collectively provide sound motive to provisionally endorse it. (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)

You can perceive things, in many respects, as they really are. For example, you can correctly see a coin as circular from most angles. Nonetheless, your perception of the world is perspectival. The coin looks different when slanted than when head-on, and there is some respect in which the slanted coin looks similar to a head-on ellipse. Many hold that perception is perspectival because you perceive certain properties that correspond to the “looks” of things. I argue that this view is (...) misguided. I consider the two standard versions of this view. What I call the PLURALIST APPROACH fails to give a unified account of the perspectival character of perception, while what I call the PERSPECTIVAL PROPERTIES APPROACH violates central commitments of contemporary psychology. I propose instead that perception is perspectival because of the way perceptual states are structured from their parts. (shrink)

It is widely held in contemporary philosophy of mind that states with underived representational content are ipso facto psychological states. This view—the Content View—underlies a number of interesting philosophical projects, such as the attempt to pick out a psychological level of explanation, to demarcate genuinely psychological from non-psychological states, and to limn the class of states with phenomenal character. The most detailed and influential theories of underived representation in philosophy are the tracking theories developed by Fodor, Dretske, Millikan and others. (...) Tracking theorists initially hoped to ‘naturalize’ underived representation by showing that although it is distinctively psychological it is not irreducibly so, yet they ended up developing theories of representation that by their own lights don’t pick out a distinctively psychological phenomenon at all. Burge sets out to develop a theory of underived representation that does pick out a distinctively psychological phenomenon. His theory promises to vindicate the Content View and the various philosophical projects that depend on it. In this paper I argue that Burge’s theory dementalizes representation for the same reason tracking theories do: These theories hold that representations are states with underived accuracy conditions, yet such states are found in all sorts of mindless systems, like plants. (shrink)