Perceptual Constancy

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 (in the case of colour constancy). One approach, becoming more common, is to account for the variation in terms of further “dimen- sions” 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)

Can young children such as 3-year-olds represent the world objectively? Some prominent developmental psychologists (Perner, 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 can’t do yet. Drawing on Tyler 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)

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)

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)

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)

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)

I defend a solution to a long-standing problem with perceptual appearances, brought about by the phenomenon of perceptual constancy. The problem is that in conditions which are non-ideal, yet within the range that perceptual constancy works, we see things veridically despite an “appearance” which is traditionally taken to be non-veridical. For example, a tilted coin is often taken to have an “elliptical appearance”, shadowed surfaces a “darker appearance”. These appearances are puzzling for a number of reasons. I defend and elaborate (...) on an approach taken by Sean Kelly, and earlier by the art historian E.H. Gombrich, according to which we can be tricked by our ability to bring about a kind of Gesltalt shift between different possible perceptual interpretations of a scene. (shrink)

In this essay, we draw on John Haugeland’s work in order to argue that Burge is wrong to think that exercises of perceptual constancy mechanisms suffice for perceptual representation. Although Haugeland did not live to read or respond to Burge’s Origins of Objectivity, we think that his work contains resources that can be developed into a critique of the very foundation of Burge’s approach. Specifically, we identify two related problems for Burge. First, if (what Burge calls) mere sensory responses are (...) not representational, then neither are exercises of constancy mechanisms, since the differences between them do not suffice to imply that one is representational and the other is not. Second, taken by themselves, exercises of constancy mechanisms are only derivatively representational, so merely understanding how they work is not sufficient for understanding what is required for something, in itself, to be representational (and thereby provide a full solution to the problem of perceptual representation). (shrink)

Abstract. Classical constructivists such as Rock and Hoffman contend that the processes of perception are intelligent and construct perceptual experience by going beyond the stimulus information or by creating a percept that deviates from the physical properties of the object. On these terms, Gibson’s theory of perception is anti-constructivist. After reviewing classical constructivism, this article maintains, first, that the phenomenology of visual space shows a deviation from physical spatial properties, by being contracted in depth, even under full cue conditions, a (...) fact that makes trouble for Gibson’s version of direct realism. Second, independently of the first argument, it contends that perception is pervasively constructed in the sense that stimulus information must be transformed to yield perception. Accordingly, perception is radically constructed in its very bones. (shrink)

In her paper, ‘Action and Self-location in Perception’, Susanna Schellenberg argues that perceptual experience of an object's intrinsic spatial properties, such as its size and shape, requires a capacity to act. More specifically, Schellenberg argues that, to have a perceptual experience of an object's intrinsic spatial properties, a subject needs to have a certain practical conception of space, or a spatial know-how. That, in turn, requires self-locating representations, which locate the subject, relative to the perceptual object, as a perceiver and (...) an agent, viz., someone who has a capacity for actions. She also makes two objections, viz., the unification objection and the sentient statue objection, to Alva Noë's sensorimotor view, a different account of how perceptual experience depends on actions. I will argue that her objections jointly render problematic not only Noë's but also her own view. (shrink)

In recent discussions of two important issues in the philosophy of perception, viz. the problems of perceptual presence and perceptual constancy, Merleau-Ponty’s ideas have been garnering attention thanks to the work of Sean Kelly and Alva Noë. Although both Kelly’s normative approach and Noë’s enactive approach highlight important aspects of Merleau-Ponty’s view, I argue that neither does full justice to it because they overlook the central role that style plays in his solution to these problems. I show that a closer (...) look at the Phenomenology and several other texts from this period reveals that, on Merleau-Ponty’s account, we are able to perceive the absent features of objects as present, constant properties, and constant objects because we recognize that the objects we perceive have a unique style that persists through and unifies all their appearances. (shrink)

In seeing a tilted penny, we are experientially aware of both its circularity and another shape, which I dub ‘β-ellipticality’. Some claim that our experiential awareness of the intrinsic shapes/sizes of everyday objects depends upon our experiential awareness of β-shapes/β-sizes. In contrast, I maintain that β-property experiences are the result of what Richard Wollheim calls ‘seeing-in’, but run in reverse: instead of seeing a three-dimensional object in a flat surface, we see a flat surface in a three-dimensional object. Using this (...) new account, I re-examine the phenomenological directness of visual experience and undermine an argument for skepticism about β-property experiences. (shrink)

Whether perceptual experience represents high-level properties like causation and natural-kind in virtue of its phenomenology is an open question in philosophy of mind. While the question of high-level properties has sparked disagreement, there is widespread agreement that the sensory phenomenology of perceptual experience presents us with low-level properties like shape and color. This paper argues that the relationship between the sensory character of experience and the low-level properties represented therein is more complex than most assume. Careful consideration of mundane examples, (...) like looking at a coin from an oblique angle, show that the low-level properties represented in experience do not necessarily figure in the sensory character of the experience. Furthermore, the sensible properties invoked when characterizing the sensory character of a perceptual experience are not necessarily included in the sensible properties represented in a perceptual experience. On this basis it is argued that perceptual experience has a disunified metaphysics, consisting in distinct sensory and cognitive components. The account is developed in relation to existing unified and disunified accounts, and discussed in terms of its implications for cognitive penetration, the reliability of introspection, the transparency of experience, and cognitive phenomenology. (shrink)

Long tradition in philosophy and in empirical psychology has it that the perceptual recovery of enduring objective size and shape proceeds through initial spatial appearance experiences—like the sensed changing visual field size of a receding car, or the shifting shape appearance of a coin as it rotates in depth. The present paper carefully frames and then critically examines such proposals. It turns out that these are contingent, empirical matters, requiring close examination of relevant research in perception science in order to (...) decide. The paper concludes with extended discussions of the empirical study of the perception of slant, size, and shape. (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)

We perceive the objective world through a subjective perceptual veil. Various perceived properties, particularly “secondary qualities” like colours and tastes, are mind-dependent. Although mind-dependent, our knowledge of many facts about the perceptual veil is immediate and secure. These are well-known facets of sense-datum theory. My aim is to carve out a conception of sense-datum theory that does not require the immediate and secure knowledge of a wealth of facts about experienced sense-data (§1). Such a theory is of value on its (...) own, given well-known challenges to epistemic foundationalism. Beyond this such a theory helps demonstrate how sense-datum theory can accommodate challenging perceptual phenomena like shape and size constancies (§3). These ideas are bridged by the roots of perceptual ambiguity (§2). In brief, tapering acquaintance knowledge creates space for perceptual representation to resolve the ambiguities in presented objects seemingly inherent in scenarios involving perceptual constancies. Thus, I offer a two-factor (acquaintance-representation) sense-datum theory to meet the challenge posed by constancies. Following Smith (2002), from whom this challenge is drawn, my focus is on shape and size constancies. Other constancies, notably colour constancy, are treated elsewhere (Brown 2014). (shrink)

Colour constancy is a foundational and yet puzzling phenomenon. Standard appearance invariantism is threatened by the psychophysical matching argument, which is taken to favour variantism. This argument, however, is inconclusive. The data at best support a pluralist view: colour constancy is sometimes variantist, sometimes invariantist. I add another potential explanation of these data, complex invariantism, which adopts an atypical six-dimensional model of colour appearance. Finally I prospect for a unifying conception of constancy among two neglected notions: discriminatory colour constancy and (...) relational colour constancy. The former arguably marks a common core capacity that is present across widely differing viewing contexts. (shrink)

This paper develops an appearance view of perception. When we see an object, we see it by having it appear some way to us. We see the object, not the appearance; but we see the object via the appearance. The appearance is subjectively conditioned: aspects of it depend on attributes of the subject. We mentally have the appearance and can reflect on it as an appearance. But in the primary instance, of veridical perception, it is the object that we focus (...) on and experience. I contrast this view with naive realism and with intentionalist or representationalist views, which I call the physical content view. I agree with these views in rejecting sense-data intermediaries and in affirming direct perception, but I argue that direct perception occurs via appearances, making mine a critical direct realism. The other views attempt to explain the spatial content of perception entirely through the physical properties of objects and their physical relation to the perceiver. I argue instead that there are ineliminably subjective aspects of normal spatial perception, which are systematically manifested as a lack of full phenomenal constancy. This systematic underconstancy can’t be accounted for at all by a consistent naive realism; for the physical content view, it requires that most of our ordinary perception is classified as illusory, violating the spirit of that view. Accepting phenomenal underconstancy as pervasive, I suggest that our ability to perceive the mind-independent properties of objects depends on developed conceptual abilities. In the final section, I compare my appearance view with the adverbialism of Chisholm and the critical direct realism of Roy Wood Sellars. (shrink)

Visual experience is shaped by a number of factors that are independent of the external objects that we perceive—factors like lighting, angle of view, and the sensitivities of photoreceptors in the retina. This paper seeks to catalog, analyze, and explain the fluctuations in visual phenomenology that are due to such factors.

Colour Relationalism asserts that colours are non-intrinsic or inherently relational properties of objects, properties that depend not only on a target object but in addition on some relation that object bears to other objects. The most powerful argument for Relationalism infers the inherently relational character of colour from cases in which one’s experience of a colour contextually depends on one’s experience of other colours. Experienced colour layering—say looking at grass through a tinted window and experiencing opaque green through transparent grey—demands (...) a contextual interdependency of one’s experience of one of these colours on one’s experience of the other. However, most if not all colour ontologies, and core perceptual experiential mechanisms like acquaintance and representation, can accommodate colour layering. It follows that experienced colour layering is consistent with colours being non-relational—this contextual interdependency of colours does not entail the constitutive dependency of one colour on the other. I utilize colour layering to examine the inference from the contextual to the constitutive interdependency of colours as it is employed in a well-known argument for Relationalism. I conclude that our justification for Relationalism is far weaker than Relationalists suggest. I first introduce readers to colour layering, then to Relationalism, and following this focus on the intersection of these topics. (shrink)

Students of perception have long known that perceptual constancy is an important aspect of our perceptual interaction with the world. Here is a simple example of the phenomenon concerning color perception: there is some ordinary sense in which an unpainted ceramic coffee cup made from a uniform material looks a uniform color when it is viewed under uneven illumination, even though the light reflected by the shaded regions to our eyes is quite different from the light reflected by the unshaded (...) regions to our eyes (see figure 1). Or consider this example concerning size perception: there is some ordinary sense in which two telephone poles look the same size when the first is viewed from 100 meters and when the second is viewed from 1 meter, even though the visual angle subtended by the two poles on our retinae is very different (see figure 2). Or consider this example concerning shape perception: there is some ordinary sense in which a penny looks round both when viewed head on and when viewed from an acute angle, even though the area projected by the penny onto our retinae under these two conditions is very different (see figure 3). Or, finally, consider this example concerning auditory volume perception (which I cannot depict graphically): there is some ordinary sense in which a speaker’s voice sounds the same volume when heard from across the room and when heard from a distance of 1 meter, even though the energy striking our ears under these two conditions is very different. (shrink)

In this paper, I consider a view that explains colour experience by the independent representation of surface and illumination. This view implies that surface colour is a phenomenal perceptual content. I argue from facts of colour phenomenology to the conclusion that surface colour is not a phenomenal perceptual content. I then argue from results of surface-matching experiments to the conclusion that surface colour is neither a perceptual content of any kind nor any sort of computational output of the perceptual system. (...) These conclusions contradict widely accepted views in both the philosophy of perception and colour science. I finish by considering and rejecting a competing account of the surface-matching results, according to which surface colour is represented indeterminately in perception. (shrink)

In 1909, Wilhelm Schapp, a student of Edmund Husserl’s at Göttingen, defended his doctoral thesis, Beiträge zur Phänomenologie der Wahrnehmung. In this text, Schapp argues that color presents things to the sense of sight by contributing a certain order, or form, that manifests itself in the orderly, predictable variation of perspectives, in the course of experience. He also argues that we do not visually perceive certain distant things, like a house far down in the valley, due to a lack of (...) such color order. While accepting, with qualifications, Schapp’s claim concerning the need for a color order, I will argue that we can visually perceive distant things. I will also argue that Schapp’s discussion of distant things is, nevertheless, of current interest, viz., by comparison of his views with Alva Noë’s recent arguments to the effect that we do not visually perceive distant objects. (shrink)

Suppose you're unable to discriminate the colors of two objects. According to the triangulation view, their colors might nonetheless look different to you, and that's something you can discover as a result of further comparisons. The primary motivation for this view is its apparent ability to solve a puzzle involving a series of pairwise indiscriminable objects. I argue that, due to visual noise, the triangulation view doesn't really solve the puzzle.

A central topic in discussions about qualia concerns their purported transparency. According to transparency theorists, an experience is transparent in the sense that the subject having the experience is aware of nothing but the intended object of the experience. In this paper this notion is criticized for failing to account for the dynamical aspects of perception. A key assumption in the paper is that perceptual content has a certain temporal depth, in the sense that each act of perception can present (...) an object as extended in time and that objects can be perceived as persisting through time. An object that is seen as persisting through time is often seen as constant and unchanging, even though the presentation of it is changing. In this paper it is argued that in order to account for these cases of perceptual constancy, we must distinguish between the awareness of having perceived that an object has a property at a certain point in time, and perceptually intending that it has that property at that point in time. Consequently, we must in at least some instances be aware of something more than the object of the experience. But precisely this distinction is rejected by the transparency theory. (shrink)

According to “actionism” (Noë 2010), perception constitutively depends on implicit knowledge of the way sensory stimulations vary as a consequence of the perceiver’s self-movement. My aim in this contribution is to develop an alternative conception of the role of action in perception present in the work of Gareth Evans using resources provided by Ruth Millikan’s biosemantic theory of mental representation.

Loosely put, colour constancy for example occurs when you experience a partly shadowed wall to be uniformly coloured, or experience your favourite shirt to be the same colour both with and without sunglasses on. Controversy ensues when one seeks to interpret ‘experience’ in these contexts, for evidence of a constant colour may be indicative a constant colour in the objective world, a judgement that a constant colour would be present were things thus and so, et cetera. My primary aim is (...) to articulate a viable conception of Present Constancy, of what occurs when a constant colour is present in experience, despite the additional presence of some experienced colour variation (e.g., correlating to a change in illumination). My proposed conception involves experienced colour layering – experiencing one opaque colour through another transparent one – and in particular requires one of those experienced layers to remain constant while the other changes. The aim is not to propose this layering conception of colour constancy as the correct interpretation of all constancy cases, but rather to develop the conception enough to demonstrate how it could and plausibly should be applied to various cases, and the virtues it has over rivals. Its virtues include a seamless application to constancy cases involving variations in filters (e.g., sunglasses) and illuminants; its ability to accommodate experiences of partial colours and error-free interpretations of difficult cases; and its broad theoretical-neutrality, allowing it to be incorporated into numerous perceptual epistemologies and ontologies. If layered constancy is prevalent, as I suspect it is, then our experiential access to colours is critically nuanced: we have been plunged into a world of colour without being told that we will rarely, if ever, look to a location and experience just one of them. (shrink)

The philosophy of perception has been mostly focused on vision, to the detriment of other modalities like audition or olfaction. In this paper I focus on olfaction and olfactory experience, and raise the following questions: is olfaction a perceptual-representational modality? If so, what does it represent? My goal in the paper is, firstly, to provide an affirmative answer to the first question, and secondly, to argue that olfaction represents odors in the form of olfactory objects, to which olfactory qualities are (...) attributed. In order to do this I develop an empirically adequate notion of olfactory object that is sensitive to the peculiarities of olfaction, and defend it against various objections. (shrink)

A central question, if not the central question, of philosophy of perception is whether sensory states have a nature similar to thoughts about the world, whether they are essentially representational. According to the content view, at least some of our sensory states are, at their core, representations with contents that are either accurate or inaccurate. Tyler Burge’s Origins of Objectivity is the most sustained and sophisticated defense of the content view to date. His defense of the view is problematic in (...) several ways. The most significant problem is that his approach does not sit well with mainstream perceptual psychology. (shrink)

Some experiments in perceptual psychology measure perceivers’ phenomenal experiences of objects versus their cognitive assessments of object properties. Analyzing such experiments, this article responds to Pizlo’s claim that much work on shape constancy before 1985 confused problems of shape ambiguity with problems of shape constancy. Pizlo fails to grasp the logic of experimental designs directed toward phenomenal aspects of shape constancy. In the domain of size perception, Granrud’s studies of size constancy in children and adults distinguish phenomenal from cognitive factors.

The dominant view among philosophers of perception is that color experiences, like color judgments, are essentially representational: as part of their very nature color experiences possess representational contents which are either accurate or inaccurate. My starting point in assessing this view is Sydney Shoemaker’s familiar account of color perception. After providing a sympathetic reconstruction of his account, I show how plausible assumptions at the heart of Shoemaker’s theory make trouble for his claim that color experiences represent the colors of things. (...) I consider various ways of trying to avoid the objection, and find all of the responses wanting. My conclusion is that we have reason to be skeptical of the orthodox view that color experiences are constitutively representational. (shrink)

It is frequently alleged that a round plate viewed from an oblique angle looks elliptical, and that when one tree is in front of another that is the same intrinsic size, the front one looks larger than the rear one. And yet there is also a clear sense in which the plate viewed from an angle looks round, and a clear sense in which the two trees look to be the same size. According to the Dual Content Theory (DCT), what (...) explains these and other similar phenomena is that perceptual experiences present us with two different sorts of spatial properties: intrinsic and perspectival spatial properties. I will argue that the Dual Content Theory is false because it rests on flawed phenomenological descriptions of the experience of spatial properties. The only conditions under which a plate tilted away and an ellipse look alike, or two objects which are different in size look the same size, is when at least one of the objects being compared is misperceived. I will consider several responses to the arguments I present, and conclude by suggesting that abandoning DCT would constitute an improvement upon Noë’s enactive theory of perception. (shrink)

All representationalists maintain that there is a necessary connection between an experience’s phenomenal character and intentional content; but there is a disagreement amongst representationalists regarding the nature of those intentional contents that are necessarily connected to phenomenal character. Russellian representationalists maintain that the relevant contents are composed of objects and/or properties, while Fregean representationalists maintain that the relevant contents are composed of modes of presentation of objects and properties. According to Fregean representationalists such as David Chalmers and Brad Thompson, the (...) Fregean variety of the view is preferable to the Russellian variety because the former can accommodate purported counterexamples involving spectrum inversion without illusion and colour constancy while the latter cannot. I maintain that colour constancy poses a special problem for the Fregean theory in that the features of the theory that enable it handle spectrum inversion without illusion cannot be extended to handle colour constancy. I consider the two most plausible proposals regarding how the Fregean view might be developed in order to handle colour constancy—one of which has recently been defended by Thompson —and argue that neither is adequate. I conclude that Fregean representationalism is no more able to accommodate colour constancy than is Russellian representationalism and, as such, ought to be rejected. (shrink)

Taken at face value, the picture of reality suggested by modern science seems radically opposed to the world as we perceive it through our senses. Indeed, it is not uncommon to hear scientists and others claim that much of our perceptual experience is a kind of pervasive illusion rather than a faithful presentation of various aspects of reality. On this view, familiar properties such as colours and solidity, to take just two examples, do not belong to external objects, but are (...) fictions generated by the brain that we mistakenly ascribe to the world around us. Contrary to this view, I argue that properties like colour and solidity are as much a part of the fabric of reality as gravity and electrons, and that our scientific and common-sense world views are not as opposed to one another as it might first appear. (shrink)

This article proposes an account of color constancy based on an examination of the relevant scientific literature. Differences in experimental settings and task instructions that lead to variation in subject performance are given particular attention. Based on the evidence discussed, the core of the proposal made is that there are two different forms of color constancy, one phenomenal and the other projective. This follows the hypothesis of Reeves et al. (Perception & Psychophysics 70:219–228, 2008). Unlike Reeves et al. (Perception & (...) Psychophysics 70:219–228, 2008), it is argued that projective color constancy is crucially dependent upon phenomenal color constancy and certain aspects of scene perception. Additionally, it is hypothesized that capacities that support projective color constancy have an important role to play in facilitating our ability to quickly recognize scenes with diagnostic chromatic properties independently of assignments of colors to object surfaces. (shrink)

A coin rotating back in depth in some sense presents a changing, elliptical shape. How are we to understand such (in this case) ‘appearances of ellipticality’? How is the experiential sense of such shifting shape appearances related to the experiential sense of enduring shape definitive of perceived shape constancy? Is the experiential recovery of surface shape based on the prior (perhaps more fundamental) recovery of point or element 3D spatial locations?—or is the perception of shape a largely independent perceptual achievement? (...) Do we gain access to enduring shape properties by first detecting and working from ‘shape appearances’? These are some of the topics taken up in this paper. (shrink)

Every perceptual experience has an objective and a subjective side. We see object size, independent of distance, but we also see that distant objects project smaller images. Early modern conceptions focused on local stimulation and thus on the subjective aspect. Helmholtz and Hering emphasized the objective aspect. Helmholtz split visual experience into two stages, with sensation representing the subjective side and perception, through cognitive processes, the objective side. Gestalt theory denied this dualism, rejecting both sensory and cognitive stages. Despite contrary (...) evidence, the sensation/perception dualism persists, in brightness models and past experience theories. That we can detect visual angle and luminance does not mean that these are raw sensations out of which perception of size and lightness is built. Size and color constancy are truly visual, not cognitive. Instructions to subjects in vision experiments must avoid the proximal mode on the one hand and cognitive judgments on the other. (shrink)

This chapter provides an overview of the phenomenology of size perception and the use of instructions to tease apart phenomenal and cognitive aspects. It develops his own recent proposals concerning the geometry of visual space. The chapter proposes that visual space is contracted along the lines of sight. This contraction would explain the apparent convergence of railway tracks, but without invoking a “proximal mode” experience. Parallel railway tracks receding into the distance project converging lines onto the retinas. A true proximal (...) mode representation would show these lines converging as if in a vertical plane. But we experience them as converging while also receding in depth along the ground. The chapter suggests that this calls for a third geometry of visual space, intermediate between a linear perspective projection and full phenomenal constancy. The chapter attributes reports of full constancy to cognitive factors. size perception, visual space, geometry, lines of sight, proximal mode, phenomenal constancy. (shrink)

Seeing happens effortlessly and yet is endlessly complex. Among the most fascinating aspects of visual perception is its stability and constancy. As we shift our gaze or move about the world, the light projected onto the retinas is constantly changing. Yet the surrounding objects appear stable in their properties. Psychologists have long been interested in the constancies. They have asked questions such as: How good is constancy? Is constancy a fact about how things look, or is it a product of (...) our beliefs and judgments about how things look? How can the contents of visual experience be studied experimentally? Philosophers have long been interested in characterizing visual experience and have become widely interested in the constancies more recently. As psychologists and philosophers have interacted, new questions have arisen: If experience is not as of retinal stimulation (proximal mode), but does not always exhibit constancy (or at least not in all respects), how shall we describe this intermediate state? Also, should we regard any departure from constancy as a failure of the visual system, or might it be a reasonable or adaptive response? In what circumstances is seeing highly conditioned by cognitive factors such as background assumptions, and in what circumstances not? Our volume focuses on size constancy and color constancy. It considers methodologies for studying conscious visual perception, efforts to describe visual experience in relation to constancy, what it means that constancy is not always perfect, and the conceptual resources needed for explaining visual experience. (shrink)

The term “perceptual constancy” was used by the Gestalt theorists in the early part of the twentieth century (e.g., Koffka 1935, 34, 90) to refer to the tendency of perception to remain invariant over changes of viewing distance, viewing angle, and conditions of illumination. This tendency toward constancy is remarkable: every change in the viewing distance, position, and illumination is necessarily accompanied by a change in the local proximal (retinal) stimulation, and yet perception remains relatively stable. The tendency toward perceptual (...) constancy encouraged the Gestalt theorists to look beyond local proximal stimulation in grounding their theories of perception. In the ensuing decades, much has been learned about the constancies. Evidence for this assertion may be found in the contributions to the current volume as well as in earlier volumes (e.g., Epstein 1977; Walsh and Kulikowsky 1998). These advances notwithstanding, significant questions remain open. Our aim here is to note some advances and specify some open questions. (shrink)

Abstract: In philosophy, perceptual constancy refers to the puzzling phenomenon of the perception of properties of objects despite our changing experience of those properties. Husserl developed a sophisticated description of perceptual constancy. In this paper I sketch Husserl's approach, which focuses on the suggestion that perception is partly constituted by the continuous interplay of intention and fulfilment. Unlike many contemporary theories, this framework gives us a way to understand the relationship between different appearances of the same object. I will show (...) how Husserl's work connects with contemporary theories which emphasize perceptual constancy from particular perspectives. These theories include appeals to perspectival properties and Cohen's counterfactual theory. Also, I show how Husserl's account shares important themes with Kelly's recent interpretation of Merleau-Ponty on perceptual constancy. (shrink)

This demonstration shows inverse gnomonic projections of flat surface areas lying in a horizontal plane tangent to the projection sphere. It shows how optical surface area varies regularly as the distance of the respective surface area from the eye varies, decreasing as the latter increases. According to ecological psychology, this kind of regularity or "invariant" is what sensory systems are designed to detect. Attunement to such invariants in the interactions of eyes and terrains make possible the perception of distance and (...) of surface walkability. (shrink)

In the philosophy of perception, direct realism has come into vogue. Philosophical authors assert and assume that what their readers want, and what anyone should want, is some form of direct realism. There are disagreements over precisely what form this direct realism should take. The majority of positions in favor now offer a direct realism in which objects and their material or physical properties constitute the contents of perception, either because we have an immediate or intuitive acquaintance with those objects (...) and properties, or because our perceptual states have informational content that represents the properties of those objects (and which is not itself an object of perception and has no specifically subjective aspect). This paper considers various forms of perceptual realism, including, for purposes of comparison, the largely abandoned indirect or representative realism. After surveying the variety of perceptual realisms and considering their various commitments, I introduce some considerations concerning the phenomenology of visual space that cause trouble for most forms of direct realism. These considerations pertain to the perception of objects in the distance and, secondarily, to the perception of shapes at a slant. I argue that one of the lesser known varieties of perceptual realism, critical direct realism, can meet the challenges offered by the facts of spatial perception. (shrink)