Most philosophical or scientific theories suppose that colour composition judgments refer to the way colours appear to us. The dominant view is therefore phenomenalist in the sense that colour composition is phenomenally given to perceivers. This paper argues that there is no evidence for a phenomenalist view of colour composition and that a conventionalist approach should be favoured.

Is color experience cognitively penetrable? Some philosophers have recently argued that it is. In this paper, we take issue with the claim that color experience is cognitively penetrable. We argue that the notion of cognitive penetration that has recently dominated the literature is flawed since it fails to distinguish between the modulation of perceptual content by non-perceptual principles and genuine cognitive penetration. We use this distinction to show that studies suggesting that color experience can be modulated by (...) factors of the cognitive system do not establish that color experience is cognitively penetrable. Additionally, we argue that even if color experience turns out to be modulated by color-related beliefs and knowledge beyond non-perceptual principles, it does not follow that color experience is cognitively penetrable since the experiences of determinate hues involve post-perceptual processes. We conclude with a brief discussion of the implications that these ideas may have on debates in philosophy. (shrink)

Consider the distinctive qualitative property grass visually appears to have when it visually appears to be green. This property is an example of what I call sensuous color. Whereas early modern mechanists typically argue that bodies are not sensuously colored, Margaret Cavendish (1623–73) disagrees. In cases of veridical perception, she holds that grass is green in precisely the way it visually appears to be. In defense of her realist approach to sensuous colors, Cavendish argues that (i) it is impossible (...) to conceive of colorless bodies, (ii) the very possibility of color experience requires that bodies are sensuously colored, and (iii) the attribution of sensuous colors to bodies provides the best explanation of color constancy. Although some passages might suggest that Cavendish endorses a reductive account of sensuous color, according to which sensuous color reduces to a body's microscopic surface texture (or some other mechanistically respectable property), I argue that she accepts a nonreductive account, on which sensuous color is not thus reducible. (shrink)

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 common for an object to present different colour appearances to different perceivers, even when the perceivers and viewing conditions are normal. For example, a Munsell chip might look unique green to you and yellowish green to me in normal viewing conditions. In such cases, there are three possibilities. Ecumenism: both experiences are veridical. Nihilism: both experiences are non-veridical. Inegalitarianism: one experience is veridical and the other is non-veridical. Perhaps the most important objection to inegalitarianism is the ignorance (...) objection, according to which inegalitarianism should be rejected because it is committed to the existence of unknowable colour facts. The goal of this paper is to show that ecumenists are also committed to unknowable colour facts. More specifically, I argue that, with the exception of colour eliminativism, all major philosophical theories of colour are committed to unknowable colour facts. (shrink)

I propose a strategy for a metaphysical reduction of perceived color, that is, an identification of perceived color with properties characterizable in non-qualitative terms. According to this strategy, a description of visual experience of color, which incorporates a description of the appearance of color, is a reference-fixing description. This strategy both takes color appearance seriously in its primary epistemic role and avoids rendering color as metaphysically mysterious. I’ll also argue that given this strategy, a (...) plausible account of perceived color claims that colors are physical properties of physical objects. (shrink)

It seems intuitively obvious that metameric matching of color samples entails a loss of information, for spectrophotometrically diverse materials appear the same. This intuition implicitly relies on a conception of the function of color vision and on a related conception of how color samples should be individuated. It assumes that the function of color vision is to distinguish among spectral energy distributions, and that color samples should be individuated by their physical properties. I challenge these (...) assumptions by articulating a different conception of the function of color vision, according to which color vision serves to partition object surfaces into discrimination classes. (shrink)

For a stable visual world, the colours of objects should appear the same under different lights. This property of colour constancy has been assumed to be fundamental to vision, and many experimental attempts have been made to quantify it. I contend here, however, that the usual methods of measurement are either too coarse or concentrate not on colour constancy itself, but on other, complementary aspects of scene perception. Whether colour constancy exists other than in nominal terms remains unclear.

I argue that Leibniz's rejection of the hypothesis of thinking matter on grounds of unintelligibility conflicts with his position on sensible qualities such as color. In the former case, he argues that thought must be a modification of something immaterial because we cannot explain thought in mechanical terms. In the latter case, however, he (rightly) grants that we cannot explain sensible qualities in mechanical terms, that is, cannot explain why a certain complex mechanical quality gives rise to the appearance (...) of a certain sensible quality, even while insisting that sensible qualities are modifications of bodies. I argue that the two cases are analogous in the relevant respects, and that Leibniz's (plausible) position on sensible qualities should have thrown his Principle of Intelligibility into doubt. (shrink)

Victor Vasarely's (1906–1997) important legacy to the study of human perception is brought to the forefront and discussed. A large part of his impressive work conveys the appearance of striking three-dimensional shapes and structures in a large-scale pictorial plane. Current perception science explains such effects by invoking brain mechanisms for the processing of monocular (2D) depth cues. Here in this study, we illustrate and explain local effects of 2D color and contrast cues on the perceptual organization in terms of (...) figure-ground assignments, i.e. which local surfaces are likely to be seen as “nearer” or “bigger” in the image plane. Paired configurations are embedded in a larger, structurally ambivalent pictorial context inspired by some of Vasarely's creations. The figure-ground effects these configurations produce reveal a significant correlation between perceptual solutions for “nearer” and “bigger” when other geometric depth cues are missing. In consistency with previous findings on similar, albeit simpler visual displays, a specific color may compete with luminance contrast to resolve the planar ambiguity of a complex pattern context at a critical point in the hierarchical resolution of figure-ground uncertainty. The potential role of color temperature in this process is brought forward here. Vasarely intuitively understood and successfully exploited the subtle context effects accounted for in this paper, well before empirical investigation had set out to study and explain them in terms of information processing by the visual brain. (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)

A quarter of a century ago, the first systematic behavioral experiments were performed to clarify the nature of color constancy—the effect whereby the perceived color of a surface remains constant despite changes in the spectrum of the illumination. At about the same time, new models of color constancy appeared, along with physiological data on cortical mechanisms and photographic colorimetric measurements of natural scenes. Since then, as this review shows, there have been many advances. The theoretical requirements for (...) constancy have been better delineated and the range of experimental techniques has been greatly expanded; novel invariant properties of images and a variety of neural mechanisms have been identified; and increasing recognition has been given to the relevance of natural surfaces and scenes as laboratory stimuli. Even so, there remain many theoretical and experimental challenges, not least to develop an account of color constancy that goes beyond deterministic and relatively simple laboratory stimuli and instead deals with the intrinsically variable nature of surfaces and illuminations present in the natural world. (shrink)

Naive observers viewed a sequence of colored Mondrian patterns, simulated on a color monitor. Each pattern was presented twice in succession, first under one daylight illuminant with a correlated color temperature of either 16,000 or 4,000 K and then under the other, to test for color constancy. The observers compared the central square of the pattern across illuminants, either rating it for sameness of material appearance or sameness of hue and saturation or judging an objective property—that is, (...) whether its change of color originated from a change in material or only from a change in illumination. Average color constancy indices were high for material appearance ratings and binary judgments of origin and low for hue–saturation ratings. Individuals’ performance varied, but judgments of material and of hue and saturation remained demarcated. Observers seem able to separate phenomenal percepts from their ontological projections of mental appearance onto physical phenomena; thus, even when a chromatic change alters perceived hue and saturation, observers can reliably infer the cause, the constancy of the underlying surface spectral reflectance. (shrink)

The thresholds of human observers detecting line targets improve significantly when the targets are presented in a spatial context of collinear inducing stimuli. This phenomenon is referred to as spatial facilitation, and may reflect the output of long-range interactions between cortical feature detectors. Spatial facilitation has thus far been observed with luminance-defined, achromatic stimuli on achromatic backgrounds. This study compares spatial facilitation with line targets and collinear, edge-like inducers defined by luminance contrast to spatial facilitation with targets and inducers defined (...) by color contrast. The results of a first experiment show that achromatic inducers facilitate the detection of achromatic targets on gray and colored backgrounds, but tend to suppress the detection of chromatic targets. Chromatic inducers facilitate the detection of chromatic targets on gray and colored backgrounds, but tend to suppress the detection of achromatic targets. Chromatic spatial facilitation appears to be strongest when inducers and background are isoluminant. The results of a second experiment show that spatial facilitation with chromatic targets and inducers requires a longer exposure duration of the inducers than spatial facilitation with achromatic targets and inducers, which is already fully effective at an inducer exposure of 30 ms only. The findings point towards two separate mechanisms for spatial facilitation with collinear form stimuli: one that operates in the domain of luminance, and one that operates in the domain of color contrast. These results are consistent with neural models of boundary and surface formation which suggest that achromatic and chromatic visual cues are represented on different cortical surface representations that are capable of selectively attracting attention. Multiple copies of these achromatic and chromatic surface representations exist corresponding to different ranges of perceived depth from an observer, and each can attract attention to itself. Color and contrast differences between inducing and test stimuli, and transient responses to inducing stimuli, can cause attention to shift across these surface representations in ways that sometimes enhance and sometimes interfere with target detection. (shrink)

Color subjectivists claim that, despite appearances to the contrary, the world external to the mind is colorless. However, in giving an account of color perception, subjectivists about the nature of perceived color must address the nature of perceived spatial location as well. The argument here will be that subjectivists’ problems with coordinating the metaphysics of perceived color and perceived location render color perception implausibly mysterious. Consequently, some version of color realism, the view that (...) colors are (physical, dispositional, functional, sui generis, or some other) properties of physical objects, is correct. (shrink)

Poorly saturated colors are closer to a pure grey than strongly saturated ones and, therefore, appear less “colorful”. Color saturation is effectively manipulated in the visual arts for balancing conflicting sensations and moods and for inducing the perception of relative distance in the pictorial plane. While perceptual science has proven quite clearly that the luminance contrast of any hue acts as a self-sufficient cue to relative depth in visual images, the role of color saturation in such figure-ground organization (...) has remained unclear. We presented configurations of colored inducers on grey ‘test’ backgrounds to human observers. Luminance and saturation of the inducers was uniform on each trial, but varied across trials. We ran two separate experimental tasks. In the relative background brightness task, perceptual judgments indicated whether the apparent brightness of the grey test background contrasted with, assimilated to, or appeared equal (no effect) to that of a comparison background with the same luminance contrast. Contrast polarity and its interaction with color saturation affected response proportions for contrast, assimilation and no effect. In the figure-ground task, perceptual judgments indicated whether the inducers appeared to lie in front of, behind, or in the same depth with the background. Strongly saturated inducers produced significantly larger proportions of foreground effects indicating that these inducers stand out as figure against the background. Weakly saturated inducers produced significantly larger proportions of background effects, indicating that these inducers are perceived as lying behind the backgrounds. We infer that color saturation modulates figure-ground organization, both directly by determining relative inducer depth, and indirectly, and in interaction with contrast polarity, by affecting apparent background brightness. The results point towards a hitherto undocumented functional role of color saturation in the genesis of form, and in particular figure-ground percepts in the absence of chromatostereopsis. (shrink)

Small changes in daylight in the environment can produce large changes in reflected light, even over short intervals of time. Do these changes limit the visual recognition of surfaces by their colour? To address this question, information-theoretic methods were used to estimate computationally the maximum number of surfaces in a sample that can be identified as the same after an interval. Scene data were taken from successive hyperspectral radiance images. With no illumination change, the average number of surfaces distinguishable by (...) colour was of the order of 10,000. But with an illumination change, the average number still identifiable declined rapidly with change duration. In one condition, the number after two minutes was around 600, after 10 min around 200, and after an hour around 70. These limits on identification are much lower than with spectral changes in daylight. No recoding of the colour signal is likely to recover surface identity lost in this uncertain environment. (shrink)

Are the following propositions true of the colors: No object can be more than one determinable or determinate color all over at the same time (Incompatibility); the colors of objects are mind-independent (Objectivism); and most human observers usually perceive the colors of objects veridically in typical conditions (Veridicality)? One reason to think not is that the empirical literature appears to support the proposition that there is mass perceptual disagreement about the colors of objects amongst human observers in typical conditions (...) (P-Disagreement). In this article, we defend Incompatibility, Objectivism, and Veridicality by calling into question whether the empirical literature really supports P-Disagreement. (shrink)

This chapter considers the ways in which whiteness as a skin color and ideology becomes a dominant level that sets the background against which all things, people and relations appear. Drawing on Merleau-Ponty's phenomenology, it takes up a series of films by Bruce Nauman and Marlon Riggs to consider ways in which this level is phenomenally challenged providing insights into the embodiment of racialization.

This paper aims to present and evaluate the (unduly neglected) account of the essence of colours developed by the early phenomenologist Adolf Reinach. Reinach claims that colours, as regards their nature or essence, are physical entities. He is opposed to the idea that colours are “subjective” or “psychic”. It might be the case that the colours we see in the world do not exist but are mere appearances. However, their non-existence would not entail any change in their essence: that (...) is, they would not be psychic, but would just be non-existent physical entities. In Reinach’s view, we can be “ontic-neutral essentialists” about colours: we can remain neutral as to the existence of colours but still make claims about their essence. In the first part of the paper, I present Reinach’s take on the essence of colours. In the second part, I address his existential neutrality about colours; in particular, I argue that Reinach’s ontic-neutral essentialism brings to the fore a seldom noted but crucial distinction to be made in the discussion of colours, that between empirical and metaphysical non-realism about colours. (shrink)

Boundary colors are observed when light from a scene is dispersed by a prism or diffraction grating. We discovered that patterns with repeating black and white stripes can produce repeating bands of boundary colors with two hues. These hues are virtually constant as measured by chromaticity or CIELAB. We found seven cases of this kind using a new appearance model for boundary colors. The model correctly predicts that green and magenta bands recur as stripe widths and dispersion strength vary. The (...) first green/magenta case in the sequence traces out an accurate ellipse in XYZ color space. Green and magenta bands are prominent in supernumerary rainbows and interference rings, and we explain why that might be the case. The explanation is based on an interesting property of the visible spectrum. In addition to the green/magenta cases, the other cases are orange/cyan, yellowish-green/purple, and yellow/violet. The success of the boundary color appearance model implies that bands are perceived as if the wavelength responses of the cones were essentially independent, which contradicts the actual behavior of cones. (shrink)

Over the last 25 years, there has been a concerted effort to settle questions about multiple realization by bringing detailed scientific evidence to bear. Ken Aizawa and Carl Gillett have pursued this scientific approach to multiple realization with a precise theory and applications. This paper reviews the application of the Dimensioned approach to human color vision, addressing objections that have appeared in the literature.

Boundary colors are observed when light from a scene is dispersed by a prism or diffraction grating. We discovered that patterns with repeating black and white stripes can produce repeating bands of boundary colors with two hues. These hues are virtually constant as measured by chromaticity or CIELAB. We found seven cases of this kind using a new appearance model for boundary colors. The model correctly predicts that green and magenta bands recur as stripe widths and dispersion strength vary. The (...) first green/magenta case in the sequence traces out an accurate ellipse in XYZ color space. Green and magenta bands are prominent in supernumerary rainbows and interference rings, and we explain why that might be the case. The explanation is based on an interesting property of the visible spectrum. In addition to the green/magenta cases, the other cases are orange/cyan, yellowish-green/purple, and yellow/violet. The success of the boundary color appearance model implies that bands are perceived as if the wavelength responses of the cones were essentially independent, which contradicts the actual behavior of cones. (shrink)

In response to recent debates in color ontology, I present an account of color that resolves the issue in a new way by conceiving of colors as properties of appearances. Appearances are both objective and subjective: they are real-world events reducible to psychophysical interactions involving environmental stimuli and experiential states. The case is made for accepting experience as an actual component of colors themselves as well as being the fundamental epistemic evidence for their instantiation.

Color relationalism holds that the colors are constituted by relations to subjects. The introspective rejoinder against this view claims that it is opposed to our phenomenally-informed, pre-theoretic intuitions. The rejoinder seems to be correct about how colors appear when looking at how participants respond to an item about the metaphysical nature of color but not when looking at an item about the ascription of colors. The present article expands the properties investigated to sound and taste and inspects the (...) mentioned asymmetry, with a particular focus on the principle of charity. Using a metaphysical item, we find that color and sound are no different from shape, our control for a clearly anti-relational property. Taste, on the other hand, is no different from likability, our control for a clearly relational property. Importantly, we find that the disparity between metaphysical and ascription items is due to participants using a principle of charity to interpret disagreement cases such that both parties can be correct. (shrink)

Navigating the ontology of color used to be a simple affair. There was the naive view that colors really are in objects the way they appear, and the view that they are secondary qualities to cause certain experiences in us. Today, there are myriad well-developed views but no satisfactory taxonomy of philosophical theories on color. In this article, I first examine the two newest taxonomies on offer and argue that they are inadequate. In particular, I look at Brogaard’s (...) taxonomy and then Cohen’s. One of the reasons I am displeased with Brogaard and Cohen’s taxonomies is that I find it implausible that dispositions are relational properties. I provide an argument against this way of classifying dispositions. Having learned from the vices and virtues of Brogaard and Cohens’ taxonomies, I provide what I believe is a much-enhanced way of taxonomizing philosophical views on color. My taxonomy rules out certain views, clarifies others, and shows that there is an unnoticed view worthy of consideration. (shrink)

There exist two widely used notions concerning the structure of phenomenal color space. The first is the notion of unique/binary hue structure, which maintains that there are four unique hues from which all other hues are composed. The second notion is the similarity structure of hues, which describes the interrelations between the hues and hence does not divide hues into two types as the first notion does. Philosophers have considered the existence of the unique/binary hue structure to be empirically (...) and phenomenally well-grounded, and the structure has been considered to be primary because this can account for the similarity structure. Consequently, the unique/binary hue structure has played a central role in color philosophy. This calls for the assessment of the justification for its existence carried out in this paper. It is concluded that, despite the prevalent view among philosophers, none of their reasons for endorsing the existence of the unique/binary hue structure are justified. Since the notion of the unique/binary hue structure appears intuitively plausible for many, however, a sketch explaining this intuition is outlined at the end. (shrink)

Significant variations in the way objects appear across different viewing conditions pose a challenge to the view that they have some true, determinate color. This view would seem to require that we break the symmetry between multiple appearances in favor of a single variant. A wide range of philosophical and non-philosophical writers have held that the symmetry can be broken by appealing to daylight viewing conditions—that the appearances of objects in daylight have a stronger, and perhaps unique, (...) claim to reveal their true colors. In this note we argue that, whatever else its merits, this appeal to daylight is not a satisfactory answer to the problem posed by perceptual variation. (shrink)

Symmetry in biological and physical systems is a product of self-organization driven by evolutionary processes, or mechanical systems under constraints. Symmetry-based feature extraction or representation by neural networks may unravel the most informative contents in large image databases. Despite significant achievements of artificial intelligence in recognition and classification of regular patterns, the problem of uncertainty remains a major challenge in ambiguous data. In this study, we present an artificial neural network that detects symmetry uncertainty states in human observers. To this (...) end, we exploit a neural network metric in the output of a biologically inspired Self- Organizing Map Quantization Error (SOM-QE). Shape pairs with perfect geometry mirror symmetry but a non-homogenous appearance, caused by local variations in hue, saturation, or lightness within and/or across the shapes in a given pair produce, as shown here, a longer choice response time (RT) for “yes” responses relative to symmetry. These data are consistently mirrored by the variations in the SOM-QE from unsupervised neural network analysis of the same stimulus images. The neural network metric is thus capable of detecting and scaling human symmetry uncertainty in response to patterns. Such capacity is tightly linked to the metric’s proven selectivity to local contrast and color variations in large and highly complex image data. (shrink)

We show that true colors as defined by Chevreul (1839) produce unsuspected simultaneous brightness induction effects on their immediate grey backgrounds when these are placed on a darker (black) general background surrounding two spatially separated configurations. Assimilation and apparent contrast may occur in one and the same stimulus display. We examined the possible link between these effects and the perceived depth of the color patterns which induce them as a function of their luminance contrast. Patterns of square-shaped inducers of (...) a single color (red, green, blue, yellow, or grey) were placed on background fields of a lighter and a darker grey, presented on a darker screen. Inducers were always darker on one side of the display and brighter on the other in a given trial. The intensity of the grey backgrounds varied between trials only. This permitted generating four inducer luminance contrasts, presented in random order, for each color. Background fields were either spatially separated or consisted of a single grey field on the black screen. Experiments were run under three environmental conditions: dark-adaptation, daylight, and rod-saturation after exposure to bright light. In a first task, we measured probabilities of contrast, assimilation, and no effect in a three-alternative forced-choice procedure (background appears brighter on the ‘left’, on the ‘right’ or the ‘same’). Visual adaptation and inducer contrast had no significant influence on the induction effects produced by colored inducers. Achromatic inducers produced significantly stronger contrast effects after dark-adaptation, and significantly stronger assimilation in daylight conditions. Grouping two backgrounds into a single one was found to significantly decrease probabilities of apparent contrast. Under the same conditions, we measured probabilities of the inducers to be perceived as nearer to the observer inducers. These, as predicted by Chevreul’s law of contrast, were determined by the luminance contrast of the inducers only, with significantly higher probabilities of brighter inducers to be seen as nearer, and a marked asymmetry between effects produced by inducers of opposite sign. Implications of these findings for theories which attempt to link simultaneous induction effects to the relative depth of object surfaces in the visual field are discussed. (shrink)

In this thesis I seek to advance our understanding of what intuitions are. I argue that intuitions are experiences of a certain kind. In particular, they are experiences with representational content, and with a certain phenomenal character. -/- In Chapter 1 I identify our target and provide some important reliminaries. Intuitions are mental states, but which ones? Giving examples helps: a person has an intuition when it seems to her that torturing the innocent is wrong, or that if something is (...) red it is coloured. We can also provide an initial characterisation of the state by saying that it has representational content, often causes belief, and appears to justify belief. In addition, there is something it is like to have an intuition: intuition has a certain phenomenal character. -/- Some argue that intuition does not explain anything which cannot be explained by other mental states. One version of this view takes intuition to reduce to belief. In Chapter 2 I argue that this entails that agents are rationally criticisable in situations where we know they are not, and that such views are therefore untenable. A parallel argument shows that the corresponding approach to perception fails. This suggests a similarity in nature: both intuition and perception are experiences. -/- Others take intuition to reduce to a disposition to have a belief. In Chapter 3 I consider a line of argument against such views, find it unsuccessful, and present two new arguments. One is likely to be dialectically ineffective. The other suffers no such weakness: it shows that the proposed reduction fails. As before, the argument also applies to perception, and suggests that intuition and perception are both experiences. -/- In the remainder of the thesis I develop an account of intuition as an experience. I distinguish between content-specific and attitude-specific phenomenology, and argue that intuition lacks the former (Chapter 4), but has the latter (Chapter 5). This allows us to say what intuition is: it is is an experience with representational content and with attitude-specific phenomenology of a certain kind. -/- In Chapter 6 I put this account of intuition to use. When a person has a perceptual or intuitional experience, I argue that simply having the experience is what makes the subject justified in believing what the experience represents. Moreover, what explains that intuition and perception can justify belief in this way is precisely their phenomenal character. (shrink)

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

I argue that perception is necessarily situation-dependent. The way an object is must not just be distinguished from the way it appears and the way it is represented, but also from the way it is presented given the situational features. First, I argue that the way an object is presented is best understood in terms of external, mind-independent, but situation-dependent properties of objects. Situation-dependent properties are exclusively sensitive to and ontologically dependent on the intrinsic properties of objects, such as their (...) shape, size, and color, and the situational features, such as the lighting conditions and the perceiver’s location in relation to the perceived object. Second, I argue that perceiving intrinsic properties is epistemically dependent on representing situation-dependent properties. Recognizing situation-dependent properties yields four advantages. It makes it possible to embrace the motivations that lead to phenomenalism and indirect realism by recognizing that objects are presented a certain way, while holding on to the intuition that subjects directly perceive objects. Second, it acknowledges that perceptions are not just individuated by the objects they are of, but by the ways those objects are presented given the situational features. Third, it allows for a way to accommodate the fact that there is a wide range of viewing conditions or situational features that can count as normal. Finally, it makes it possible to distinguish perception and thought about the same object with regard to what is represented. (shrink)

On the face of it, suffering from the loss of a loved one and suffering from intense pain are very different things. What makes them both experiences of suffering? I argue it’s neither their unpleasantness nor the fact that we desire not to have such experiences. Rather, what we suffer from negatively transforms the way our situation as a whole appears to us. To cash this out, I introduce the notion of negative affective construal, which involves practically perceiving our situation (...) as calling for change, registering this perception with a felt desire for change, and believing that the change is not within our power. We (attitudinally) suffer when negative affective construal is pervasive, either because it colours a large swath of possibilities, as in the case of anxiety, or because it narrows our attention to what hurts, as in the case of grief. On this view, sensory or bodily suffering is a special case of attitudinal suffering: the unpleasantness of pain causes pervasive negative affective construal. Pain that doesn’t negatively transform our world doesn’t make for suffering. (shrink)

Blindsight is a kind of residual vision found in people with lesions to V1. Subjects with blindsight typically report no visual awareness, but they are nonetheless able to make above-chance guesses about the shape, location, color and movement of visual stimuli presented to them in their blind field. A different kind of blindsight, sometimes called type 2 blindsight, is a kind of residual vision found in patients with V1 lesions in the presence of some residual awareness. Type 2 blindsight (...) differs from ordinary visual experience in lacking the particularity, transparency and fine-grainedness often taken to be essential to visual experience, at least in veridical cases. I argue that the case of type 2 blindsight provides a counterexample to the view that these characteristics are essential to veridical visual experience and that this gives us reason to resist the view that visual experience is essentially a perceptual relation to external objects. In the second part of the paper I argue that the case of type 2 blindsight yields important insights into the effects of attentional modulation on perceptual content and that cases of attentional modulation of appearance are not at odds with the view that the phenomenology of visual experience flows from its content. (shrink)

To study conscious experience we must, to some extent, trust introspective reports; yet introspective reports often do not merit our trust. A century ago, E.B. Titchener advocated extensive introspective training as a means of resolving this difficulty. He describes many of his training techniques in his four-volume laboratory manual of 1901- 1905. This paper explores Titchener's laboratory manual with an eye to general questions about the prospects of introspective training for contemporary consciousness studies, with a focus on the following examples: (...) introspective knowledge of the combination tones that arise when a musical interval is played; the 'flight of colours' in the afterimage of a field of bright, broad- spectrum light; and the possibility of non-obvious visual illusions. Introspective training appears to have some merit, but also to involve significant hazards. (shrink)

A preview of my book *Perception*. Discusses the relationship between perception and the physical world and the issue of whether reality is as it appears. Useful examples are included throughout the book to illustrate the puzzles of perception, including hallucinations, illusions, the laws of appearance, blindsight, and neuroscientific explanations of our experience of pain, smell and color. The book covers both traditional philosophical arguments and more recent empirical arguments deriving from research in psychophysics and neuroscience. The addition of chapter (...) summaries, suggestions for further reading and a glossary of terms make Perception essential reading for anyone studying the topic in detail, as well as for students of philosophy of mind, philosophy of psychology and metaphysics. (shrink)

Whenever we communicate, we inevitably have to say one thing before another. This means introducing particularly subtle patterns of salience into our language. In this paper, I introduce ‘order-based salience patterns’, referring to the ordering of syntactic contents where that ordering, pretheoretically, does not appear to be of consequence. For instance, if one is to describe a colourful scarf, it wouldn’t seem to matter if one were to say it is ‘orange and blue’ or ‘blue and orange’. Despite their apparent (...) triviality, I argue that order-based salience patterns tend to make the content positioned first more salient – in the sense of attention-grabbing – in a way that can have surprising normative implications. Giving relative salience to gender differences over similarities, for instance, can result in the activation of cognitively accessible beliefs about gender differences. Where those beliefs are epistemically and/or ethically flawed, we can critique the salience pattern that led to them, providing an instrumental way of evaluating those patterns. I suggest that order-based salience patterns can also be evaluated on constitutive grounds; talking about gender differences before similarities might constitute a subtle form of bias. Finally, I reflect on how the apparent triviality of order-based salience patterns in language gives them an insidious strength. (shrink)

Whether we perceive high-level properties is presently a source of controversy. A promising test case for whether we do is aesthetic perception. Aesthetic properties are distinct from low-level properties, like shape and colour. Moreover, some of them, e.g. being serene and being handsome, are properties we appear to perceive. Aesthetic perception also shares a similarity with gestalt effects, e.g. seeing-as, in that aesthetic properties, like gestalt phenomena, appear to ‘emerge’ from low-level properties. Gestalts effects, of course, are widely observed, which (...) raises the question: do gestalt effects make it plausible that we perceive high-level aesthetic properties? Contra Stokes, this paper argues that they don’t. This is interesting in its own right, but it also points to a more general lesson, namely we should resist the temptation to appeal to gestalt effects to argue for high-level perception. (shrink)

[What It’s Like, or What It’s About? The Place of Consciousness in the Material World] Summary: The book is both a survey of the contemporary debate and a defense of a distinctive position. Most philosophers nowadays assume that the focus of the philosophy of consciousness, its shared explanandum, is a certain property of experience variously called “phenomenal character,” “qualitative character,” “qualia” or “phenomenology,” understood in terms of what it is like to undergo the experience in question. Consciousness as defined in (...) terms of its phenomenal aspect is often called “phenomenal consciousness.” The major issue that occupies most thinkers is whether this phenomenal character happens to be a physical property, or whether it is rather sui generis. Those who believe the former are materialists; those who conclude the latter are dualists. As the currently dominant metaphysic is materialism – also sometimes called physicalism – the challenge appears to be to slot phenomenal properties among the physical properties that ultimately make up the world. David Chalmers argued powerfully that we can go very far in situating many mental properties in the physical world – namely, the properties that can be understood in functional terms – but that phenomenal properties resist such a treatment. Chalmers calls this “the hard problem” of consciousness. But there are also some quite powerful positive arguments for dualism. The two most influential ones are the modal argument, also offered by Chalmers, and the knowledge argument invented by Frank Jackson. Chalmers invites us to conceive of creatures that are exactly like human beings – physically, functionally, behaviorally – only bereft of phenomenal consciousness. If such creatures are conceivable, says Chalmers, they are metaphysically possible. And if they are metaphysically possible, materialism is false. Jackson, for his part, suggests we imagine Mary who has spent her entire life inside a black-and-white room and has seen the world through a black-and-white TV screen. But she also happens to know everything there is to know about the physics of color. And yet, Jackson suggests that once Mary is finally released from her room and sees a lawn outside, she learns something new: that this is what it is like to experience green color. The current work on consciousness is by and large characterized by attempts to answer these two dualistic arguments. I try to make sense of the positions within the domain of philosophy of consciousness by means of two major distinctions that mutually intersect. First, there is a distinction between dualism and materialism. An apparent third alternative currently on offer, the so-called Russellian monism, is unstable, collapsing into either dualism (panpsychism) or materialism (Russellian physicalism). Materialism comes in two main flavors: either the a posteriori physicalism, which detects an epistemic gap between phenomenal and physical truths, hence denying that the former could be derived from the latter; or the a priori physicalism, which does not acknowledge any such obstacle. The second major distinction is between phenomenism and representationalism. It’s true that Ned Block, who introduced this contrast, meant to distinguish between two kinds of materialism. But I believe that the distinction actually intersects the one between materialism and dualism. We thus arrive at a table with six slots, representing six main positions in the philosophy of consciousness: (1) dualist phenomenism (Chalmers, the early Jackson, and Tyler Burge); (2) dualist representationalism (René Descartes); (3) aposteriori materialist phenomenism (Block); (4) a posteriori materialist representationalism (Michael Tye, Fred Dretske, David Rosenthal); (5) a priori materialist phenomenism (David Lewis); and (6) a priori materialist representationalism (Daniel Dennett, Derk Pereboom). However, this scheme is in fact somewhat misleading. It is true that Dennett is usually classified as an apriori materialist (or, more precisely an apriori materialist representationalist), but I believe that needs to be corrected. In order to understand why, I first analyze varieties of materialist representationalism in detail, in particular various construals of phenomenal character in terms of representation, or intentionality, which includes a discussion of the identity of its content (the issue of externalism). By contrast, Dennett rejects the concept of phenomenal character. Consciousness has no intrinsic, publicly inaccessible properties. On that ground, Dennett builds an empirical, fully functionalist theory of consciousness, which he also tries to integrate within a general Darwinian framework. From that point of view, one can contrast Dennettian and representationalist views on the issue of animal consciousness. In addition to his rejection of phenomenal character, Dennett also abstains from the regular metaphysical departure point of regular materialism. He does not so much ask how an enigmatic property of consciousness fits an antecedently characterized world, but rather how far we can investigate all aspects of the world, including consciousness, using the scientific method. He is thus a methodological naturalist, rather than a metaphysical materialist. While this approach removes obstacles to the science of consciousness, it does not solve what might be called “the hardest problem” – of intentionality, not phenomenal consciousness. The hardest problem consists in the fact that our intentional discourse involves conflicting commitments that prevent a coherent metaphysic of representational states. However, it does not follow that we should give up on this discourse as a theoretical means of reduction as well as a practical tool of explanation. But it might be that intentional discourse is a somewhat pseudo one. (shrink)

Philosophical reflection on racial profiling tends to take one of two forms. The first sees it as an example of ‘statistical discrimination,’ (SD), raising the question of when, if ever, probabilistic generalisations about group behaviour or characteristics can be used to judge particular individuals.(Applbaum 2014; Harcourt 2004; Hellman, 2014; Risse and Zeckhauser 2004; Risse 2007; Lippert-Rasmussen 2006; Lippert-Rasmussen 2007; Lippert-Rasmussen 2014) . This approach treats racial profiling as one example amongst many others of a general problem in egalitarian political philosophy, (...) occasioned by the fact that treating people as equals does not always require, or permit, us to treat them the same. The second form is concerned with how racial profiling illuminates the nature, justification, and reproduction of hierarchies of power and privilege based on skin colour and morphology. This form of reflection on racial profiling is therefore less about the justification for judging people based on the characteristics of the group to which they (appear to) belong, and more concerned with the specific ways in which the association of racialized minorities – and, in particular, black people – with crime, contributes to, and reflects, racial inequality, and oppression.(Kennedy 1998; Zack, 2015; Lever, 2005; Lever 2007). Both approaches to profiling have much to recommend them and, taken together, they form an essential component of the political philosophy of race. The statistical approach has the merits of linking racial profiling, as practice, to a body of other practices that generate and justify inequalities based on factors other than race, but it typically offers little by way of insight into the role of racial profiling itself in sustaining racial inequality and injustice. The racial construction approach, for obvious reasons, is rather better at the latter task, but its insights tend to come at the price of a broader understanding of the ways in which inequality is reproduced and justified, or of the ethical dilemmas raised by our competing claims to security. As we will see, insights from both approaches can be synthesized to clarify what, if anything, is wrong with racial profiling and what broader conclusions for equality and security follow from the study of profiling. (shrink)

An elderly patient in a care home only wants human nurses to provide her care – not robots. If she selected her carers based on skin colour, it would be seen as racist and morally objectionable, but is choosing a human nurse instead of a robot also morally objectionable and speciesist? A plausible response is that it is not, because humans provide a better standard of care than robots do, making such a choice justifiable. In this paper, I show why (...) this response is incorrect, because robots can theoretically care as well as human nurses can. I differentiate between practical caring and emotional caring, and I argue that robots can match the standard of practical care given by human nurses, and they can simulate emotional care. There is growing evidence that people respond positively to robotic creatures and carebots, and AI software is apt to emotionally support patients in spite of the machine’s own lack of emotions. I make the case that the appearance of emotional care is sufficient, and need not be linked to emotional states within the robot. After all, human nurses undoubtedly ‘fake’ emotional care and compassion sometimes, yet their patients still feel adequately cared for. I show that it is a mistake to claim that ‘the human touch’ is in itself a contributor to a higher standard of care; ‘the robotic touch’ will suffice. Nevertheless, it is not speciesist to favour human nurses over carebots, because carebots do not suffer as the result of such a choice. (shrink)

Imagine two urns, each with a thousand beads - in one all the beads are blue while in the other only one of the thousand is blue. If one of these urns is pushed forward (based on the toss of a fair coin) and the single bead then randomly drawn from it is blue, we must infer that it is a thousand times more probable that the urn pushed forward is the purely blue one. The hypothesis that this was instead (...) the urn with only one blue bead would require that the occurrence of the evidence, the blue bead being drawn, was something improbable - and it is improbable that something improbable is what has occurred. Next consider an example of only one urn with no prior description. By the same reasoning as above, if all the first beads randomly drawn are blue, it is becoming more and more probable that the beads in the urn are generally blue. (Otherwise something improbable would be happening in another colour not appearing; and what’s improbable is improbable.) It is therefore probable also that the next bead drawn will be blue. This is induction. As Hume would have said, we could not know a priori, given this evidence, that the next bead will be blue. But, as he overlooked, we can know a priori, given this evidence, that it is probable that the next bead will be blue. In neither urn example has the belief regarding the beads been formed as a Humean habit of expectation after many observations of beads. (In the first case there is only one observation. The second could be modified to have all the beads drawn out at once.) Rather the belief is a product of a priori reasoning about probability. Next imagine that a coin has been tossed a thousand times and landed heads every time. There was a fair and a loaded coin. According to the same reasoning, it is overwhelmingly more probable that the coin used was the loaded one. For that the fair coin had so landed is most improbable. The hypothesis that there is no external world makes the orderliness in my current experience improbable - much like getting all heads with a fair coin. (Uncaused sensation would most probably be chaotic.) The most probable hypothesis is that of things like those we believe in causing this orderliness - as the coin’s being loaded would have caused all heads. The hypothesis that my experience has been made to take this pattern by a Cartesian malicious demon or by scientists controlling my brain in a vat can only falsely seem to make the character of the experience probable by sneaking in an inherently improbable ad hoc specification that this sort of pattern of experience was that which they were aiming at producing - like an ad hoc specification that the fair coin was one that by chance landed heads all thousand times. We may thus reject such hypotheses as improbable. So this is the problem of induction solved and scepticism answered through a priori reasoning. (shrink)

A crucial socio-political challenge for our age is how to rede!ne or extend group membership in such a way that it adequately responds to phenomena related to globalization like the prevalence of migration, the transformation of family and social networks, and changes in the position of the nation state. Two centuries ago Immanuel Kant assumed that international connectedness between humans would inevitably lead to the realization of world citizen rights. Nonetheless, globalization does not just foster cosmopolitanism but simultaneously yields the (...) development of new group boundaries. Group membership is indeed a fundamental issue in political processes, for: “the primary good that we distribute to one another is membership in some human community” – it is within the political community that power is being shared and, if possible, held back from non-members. In sum, it is appropriate to consider group membership a fundamental ingredient of politics and political theory. How group boundaries are drawn is then of only secondary importance. Indeed, Schmitt famously declared that “[e]very religious, moral, economic, ethical, or other antithesis transforms into a political one if it is suffciently strong to group human beings e#ectively according to friend and enemy”. Even though Schmitt’s idea of politics as being constituted by such antithetical groupings is debatable, it is plausible to consider politics among other things as a way of handling intergroup di#erences. Obviously, some of the group-constituting factors are more easily discernable from one’s appearance than others, like race, ethnicity, or gender. As a result, factors like skin color or sexual orientation sometimes carry much political weight even though individuals would rather con!ne these to their private lives and individual identity. Given the potential tension between the political reality of particular groupmembership defnitions and the – individual and political – struggles against those definitions and corresponding attitudes, citizenship and civic behavior becomes a complex issue. As Kymlicka points out, it implies for citizens an additional obligation to non-discrimination regarding those groups: “[t]his extension of non-discrimination from government to civil society is not just a shift in the scale of liberal norms, it also involves a radical extension in the obligations of liberal citizenship”. Unfortunately, empirical research suggests that political intolerance towards other groups “may be the more natural and ‘easy’ position to hold”. Indeed, since development of a virtue of civility or decency regarding other groups is not easy, as it often runs against deeply engrained stereotypes and prejudices, political care for matters like education is justified. Separate schools, for example, may erode children’s motivation to act as citizens, erode their capacity for it and!nally diminish their opportunities to experience transcending their particular group membership and behave as decent citizens. This chapter outlines a possible explanation for such consequences. That explanation will be found to be interdisciplinary in nature, combining insights from political theory and cognitive neuroscience. In doing so, it does not focus on collective action, even though that is a usual focus for political studies. For example, results pertaining to collective political action have demonstrated that the relation between attitudes and overt voting behavior or political participation is not as direct and strong as was hoped for. Several conditions, including the individual’s experiences, self-interest, and relevant social norms, turned out to interfere in the link between his or her attitude and behavior. Important as collective action is, this chapter is concerned with direct interaction between agents and the in$uence of group membership on such interaction – in particular joint action. Although politics does include many forms of action that require no such physical interaction, such physical interaction between individuals remains fundamental to politics – this is the reason why separate schooling may eventually undermine the citizenship of its isolated pupils. This chapter will focus on joint action, de!ned as: “any form of social interaction whereby two or more individuals coordinate their actions in space and time to bring about a change in the environment”. Cognitive neuroscienti!c evidence demonstrates that for such joint action to succeed, the agents have to integrate the actions and expected actions of the other person in their own action plans at several levels of speci!city. Although neuroscienti!c research is necessarily limited to simple forms of action, this concurs with a philosophical analysis of joint action, which I will discuss below. (shrink)

Common everyday materials such as textiles, foodstuffs, soil or skin can have complex, mutable and varied appearances. Under typical viewing conditions, most observers can visually recognize materials effortlessly, and determine many of their properties without touching them. Visual material perception raises many fascinating questions for vision researchers, neuroscientists and philosophers, yet has received little attention compared to the perception of color or shape. Here we discuss some of the challenges that material perception raises and argue that further philosophical (...) thought should be directed to how we see materials. (shrink)

Four experiments investigated the extent to which abstract quantitative information can be conveyed by basic visual features. This was done by asking observers to estimate and discriminate Pearson correlation in graphical representations where the first data dimension of each element was encoded by its horizontal position, and the second by the value of one of its visual features; perceiving correlation then requires combining the information in the two encodings via a common abstract representation. Four visual features were examined: luminance, (...) class='Hi'>color, orientation, and size. All were able to support the perception of correlation. Indeed, despite the strikingly different appearances of the associated stimuli, all gave rise to performance that was much the same: just noticeable difference was a linear function of distance from complete correlation, and estimated correlation a logarithmic function of this distance. Performance differed only in regards to the level of noise in the feature, with these values compatible with estimates of channel capacity encountered in classic experiments on absolute perceptual magnitudes. These results suggest that quantitative information can be conveyed by visual features that are abstracted at relatively low levels of visual processing, with little representation of the original sensory property. It is proposed that this is achieved via an abstract parameter space in which the values in each perceptual dimension are normalized to have the same means and variances, with perceived correlation based on the shape of the joint probability density function of the resultant elements. (shrink)

Mimicry, camouflage, transvestism, chance or cryptic anamorphism, fascination – all ways of changing clothes, habits and habitats in nature as well as in culture, in any symbolic field created by human beings during their history. Art and artification, aestheticization, stylization and beautification are all practices reflecting the need and desire for biological as well as social adaptation, all performances producing functional and fictional frames, boundaries or hierarchies in ordinary life, including the artworld. They can persuade and convince by creating consensus (...) and belief, but they can also lead to a different common sense, a sensorium – a sensorial medium and an aesthetic mediation open to a new world and to new experiences. -/- By investigating mimetism as a fundamental and polymorphic aesthetic performance, this issue of «Aisthesis» aims to rethink the concept, value, and function of mimesis and its media in the context of camouflage, simulation, and dissimulation, where images do not reveal themselves as such, but are to be perceived unambiguously as what they are not – as hieroglyphs or puzzles. In the animal kingdom, as well as in war or in ordinary public life, camouflage consists in taking on the traits, colours, and shapes of a given form or environment. This is a twofold process: on the one hand, by blending two or more shapes in one, the camoufleur seeks to remain hidden and to mislead the others in order to keep a vital secret or an ephemeral whim; on the other hand, however, he/she aims to be recognized by a specific milieu or group, thus betraying a craving for communication and familiarity, as well as a need to convey an agreeable appearance and to share a way of life. (shrink)

As physical entities that translate symbols into physical actions, computers offer insights into the nature of meaning and agency. • Physical symbol systems, generically known as agents, link abstractions to material actions. The meaning of a symbol is defined as the physical actions an agent takes when the symbol is encountered. • An agent has autonomy when it has the power to select actions based on internal decision processes. Autonomy offers a partial escape from constraints imposed by direct physical influences (...) such as gravity and the transfer of momentum. Swimming upstream is an example. • Symbols are names that can designate other entities. It appears difficult to explain the use of names and symbols in terms of more primitive functionality. The ability to use names and symbols, i.e., symbol grounding, may be a fundamental cognitive building block. • The standard understanding of causality—wiggling X results in Y wiggling—applies to both physical causes (e.g., one billiard ball hitting another) and symbolic causes (e.g., a traffic light changing color). Because symbols are abstract, they cannot produce direct physical effects. For a symbol to be a cause requires that the affected entity determine its own response. This is called autonomous causality. • This analysis of meaning and autonomy offers new perspectives on free will. (shrink)