Color experience is structured. Some ?unique? colors (red, green, yellow, and blue) appear as ?pure,? or containing no trace of any other color. Others can be considered as a mixture of these colors, or as ?binary colors.? According to a widespread assumption, this unique/binary structure of color experience is to be explained in terms of neurophysiological structuring (e.g., by opponent processes) and has no genuine explanatory basis in the physical stimulus. The argument from structure builds on these assumptions to argue (...) that colors are not properties of surfaces and that color experiences are neural processes without environmental counterparts. We reconsider the argument both in terms of its logic and in the light of recent models in vision science which point at environment-involving patterns that may be at the basis of the unique/binary structure of color experience. We conclude that, in the light of internal and external problems which arise for it, the argument from structure fails. (shrink)

The problem of nonreflectors perceived as colored is the central problem for Byrne & Hilbert's (B&H's) physicalism. Vision scientists and other interested parties need to consider the motivation for their account of “productance physicalism.” Is B&H's theory motivated by scientific concerns or by philosophical interests intended to preserve a physicalist account of color as a posteriori necessary?

Reflectance physicalism only provides a partial picture of the ontology of color. Byrne & Hilbert’ account is unsatisfactory because the replacement of reflectance functions by productance functions is ad hoc, unclear, and only leads to new problems. Furthermore, the effects of color contrast and differences in illumination are not really taken seriously: Too many “real” colors are tacitly dismissed as illusory, and this for arbitrary reasons. We claim that there cannot be an all-embracing ontology for color.

The colors we perceive are the outcome of an attempt to meaningfully order the spectral information from the environment. These colors are not the result of a straightforward mapping of a physical property to a sensation, but arise from an interaction between our environment and our visual system. Thus, although one may infer from a surface’ reflectance characteristics that it will be perceived as “colored,” true colors only arise by virtue of the interaction of the reflected light with the eye (...) (and brain) of an observer. (shrink)

This paper elaborates on an argument in my book *Perception*. It has two parts. In the first part, I argue against what I call "basic" naive realism, on the grounds that it fails to accommodate what I call "internal dependence" and it requires an empirically implausible theory of sensible properties. Then I turn Craig French and Ian Phillips’ modified naïve realism as set out in their recent paper "Austerity and Illusion". It accommodates internal dependence. But it may retain the empirically (...) implausible theory of sensible properties. And it faces other empirical problems. Representationalism about experiences avoids those problems and is to be preferred. (shrink)

In many cases of variation in color vision, there is no non-arbitrary way of choosing between variants. Byrne and Hilbert insist that there is an unknown standard for choosing, while eliminativists claim that all the variants are erroneous. A better response relativizes colors to perceivers, thereby providing a color realism that avoids the need to choose between variants.

We argue that any theory of color physicalism must include consideration of ecological interactions. Ecological and sensorimotor contingencies resulting from relative surface motion and observer motion give rise to measurable effects on the spectrum of light reflecting from surfaces. These contingencies define invariant manifolds in a sensory-spatial space, which is the physical underpinning of all subjective color experiences.

Many favor representationalism about color experience. To a first approximation, this view holds that experiencing is like believing. In particular, like believing, experiencing is a matter of representing the world to be a certain way. Once you view color experience along these lines, you face a big question: do our color experiences represent the world as it really is? For instance, suppose you see a tomato. Representationalists claim that having an experience with this sensory character is necessarily connected with representing (...) a distinctive quality as pervading a round area out there in external space. Let us call it “sensible redness” to highlight the fact that the representation of this property is necessarily connected with the sensory character of the experience. Is this property, sensible redness, really co-instantiated with roundness out there in the space before you? (shrink)

Qualia internalism is the thesis that qualia are intrinsic to their subjects: the experiences of intrinsic duplicates have the same qualia. Content externalism is the thesis that mental representation is an extrinsic matter, partly depending on what happens outside the head. 1 Intentionalism comes in strong and weak forms. In its weakest formulation, it is the thesis that representationally identical experiences of subjects have the same qualia. 2.

The target article is an attempt to make some progress on the problem of color realism. Are objects colored? And what is the nature of the color properties? We defend the view that physical objects (for instance, tomatoes, radishes, and rubies) are colored, and that colors are physical properties, specifically types of reflectance. This is probably a minority opinion, at least among color scientists. Textbooks frequently claim that physical objects are not colored, and that the colors are "subjective" or "in (...) the mind." The article has two other purposes: first, to introduce an interdisciplinary audience to some distinctively philosophical tools that are useful in tackling the problem of color realism and, second, to clarify the various positions and central arguments in the debate. (shrink)

Our reply is in three parts. The first part concerns some foundational issues in the debate about color realism. The second part addresses the many objections to the version of physicalism about color ("productance physicalism") defended in the target article. The third part discusses the leading alternative approaches and theories endorsed by the commentators.

Aristotle held that perception consists in the reception of external sensory qualities (or sensible forms) in the sensorium. This idea is repeated in many forms in contemporary philosophy, including, with regard to vision, in the idea (still not firmly rejected) that the retinal image consists of points of colour. In fact, this is false. Colour is a quality that is constructed by the visual system, and though it is possible to be a realist about colour, it is completely misleading to (...) think of it as received by the retina. Moreover, such supposedly “charitable” interpretations of Aristotle’s doctrines, based on miscon- ceptions of perception-science, distort our understanding of his historical context. (shrink)

Byrne & Hilbert (B&H) assert that reflectances embody the reality of color, but metamerism smears the authors' “real” color categories into uselessness. B&H ignore this problem, possibly because they implicitly adopt a sort of subjectivism, whereby an object is defined by the percepts (or more generally by the measurements) it engenders. Subjectivism is unwieldy, and hence prone to such troubles.

Byrne & Hilbert defend color realism, which assumes that: (a) colors are properties of objects; (b) these objects are physical; hence, (c) colors are physical properties. I accept (a), agree that in a certain sense (b) can be defended, but reject (c). Colors are properties of perceptual objects – which also have underlying physical properties – but they are not physical properties.

To identify the set of reflectances that constitute redness, the authors must first determine which surfaces are red. They do this by relying on widespread agreement among us. However, arguments based on the possible ways in which humans would perceive colors show that mere widespread agreement among us is not a satisfactory way to determine which surfaces are red.

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)

A stubborn problem for reflectance physicalism about color is to account for individual differences in normal trichromat color perception. The identification of determinate colors with physical properties of visible surfaces in a universal, perceiver-independent way is challenged by the observation that the same surfaces in identical viewing conditions often look different in color to different human subjects with normal color vision. Recently, leading representatives of reflectance physicalism have offered some arguments to defend their view against the individual differences challenge. In (...) this paper I challenge their defense. I argue thateven though individual differences are present in shape perception as well as in color perception, the mechanisms of shape perception and those of color perception differ in ways which make them completely different regarding their evidential status for certain identity claims. Thus comparing color perception to shape perception offers no support for identifying hues with reflectances. On the other hand, drawing a parallel between the temperature-mean kinetic energy of molecules (MKE) identification and the proposed hue-reflectance identities is no support for reflectance physicalism either, since there is an important disanalogybetween the two cases. While individual differences obtain in color perception, the effects of temperature (e.g., melting, thermal expansion) do not exhibit analogous variation, which makes the temperature-MKE identification unproblematic compared to the hue-reflectance identification. One motivation for this ongoing debate is that the success or failure of reflectance physicalism has far-reaching consequences regarding externalist theories of phenomenal consciousness. (shrink)

I will develop a new problem for almost all realist theories of colour. The problem involves fluctuations in our colour experiences that are due to visual noise rather than changes in the objects we are looking at.

Colours and consciousness both present us with metaphysical problems. But what exactly are the problems? According to standard accounts, they are roughly the following. On the one hand, we have reason to believe, about both colour and consciousness, that they are identical with some familiar natural phenomena. But on the other hand, it is hard to see how these identities could obtain. I argue that this is an adequate characterisation of our metaphysical problem of colour, but a mischaracterisation of the (...) problem of consciousness. It mischaracterises the problem by presenting consciousness as more 'colour-like' than we have reason to take it to be. The real problem of consciousness is, I suggest, that almost nothing theoretically useful is known about this phenomenon at present. I also explore some implications of this perspective on the problem of consciousness. Given the shape of the problem, I argue that we can't rule out all forms of eliminativism about consciousness. Nor can we rule out that future research will close the ' explanatory gap' that consciousness gives rise to. (shrink)

Larry Hardin has been the most steadfast and influential critic of physicalist theories of color over the last 20 years. In their modern form these theories originated with the work of Smart and Armstrong in the 1960s and 1970s1 and Hardin appropriately concentrated on their views in his initial critique of physicalism.2 In his most recent contribution to this project3 he attacks Michael Tye’s recent attempts to defend and extend color physicalism.4 Like Byrne and Hilbert5, Tye identifies color with the (...) reflecting properties of objects (“reflectance physicalism”). Specifically, the determinate and determinable colors are identified with types of reflectances. (Setting some complications aside, the reflectance of an object is the proportion of light that it reflects at each wavelength in the visible spectrum.) These reflectance types are, in the terminology of Hilbert, anthropocentric—in the terminology of Lewis6, they are not very “natural”. (shrink)

While color realism is endorsed, Byrne & Hilbert's (B&H's) case for it stretches the notion of “physical property” beyond acceptable bounds. It is argued that a satisfactory account of color should do much more to respond to antirealist intuitions that flow from the specificity of color experience, and a pointer to an approach that does so is provided.

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)

Color-vision defects constitute a spectrum of disorders with varying degrees and types of departure from normal human color vision. One form of color-vision defect is dichromacy; by mixing together only two lights, the dichromat can match any light, unlike normal trichromatic humans, who need to mix three. In a philosophical context, our titular question may be taken in two ways. First, it can be taken at face value as a question about visible properties of external objects, and second, it may (...) be interpreted as the more intangible question of “what it’s like” to be color-blind. (shrink)

Michael Tye has recently been a vocal defender of color realism or, as I shall call it, color objectivism. Objectivism about color is the view that color properties are identical to intrinsic physical properties of the surfaces of objects. Subjectivism about color is the denial of color objectivism. Objectivists argue that color claims must be taken at face value. In this paper I forego the usual bickering about whether there are surface reflectance properties that can be identified with colors as (...) the objectivist theory requires. Supposing that some such properties could be found, I argue that if objectivism about color were correct it would have the unsavory consequence that we are rarely if ever right—perhaps never right—about the particular colors of particular things. So objectivism does not bear out common attribution of colors to the surfaces of things, after all. (shrink)

We examine the pros and cons of color realism, exposing some desiderata on a theory of color: the theory should render colors as scientifically legitimate and correctly individuated, and it should explain how we have veridical color experiences. We then show that these desiderata can by met by treating colors as properties of the special sciences. According to our view, some of the major as properties of the special sciences. According to our view, some of the major disputes in the (...) literature about color -- anti-realism versus dispositionalism versus reductionism -- are not well-founded at this stage of scientific inquiry. Our account of color is designed to be of use in the sciences and as such is driven largely by considerations of what the various sciences need in order to proceed appropriately. We argue that a scientific theory of colors need not regard colors as anything more than high-level statistical constructs built out of correlations between color experiences and other phenomena. (shrink)

There has been some recent optimism that addressing the question of how we distinguish sensory modalities will help us consider whether there are limits on a scientific understanding of perceptual states. For example, Block has suggested that the way we distinguish sensory modalities indicates that perceptual states have qualia which at least resist scientific characterization. At another extreme, Keeley argues that our common-sense way of distinguishing the senses in terms of qualitative properties is misguided, and offers a scientific eliminativism about (...) common-sense modalities which avoids appeal to qualitative properties altogether. I’ll argue contrary to Keeley that qualitative properties are necessary for distinguishing senses, and contrary to Block that our common-sense distinction doesn’t indicate that perceptual states have qualia. A non-qualitative characterization of perceptual states isn’t needed to avoid the potential limit on scientific understanding imposed by qualia. (shrink)

Phenomenal intentionality is a singular form of intentionality. Science shows it is internally-determined. So standard externalist models for reducing intentionality don't apply to it.

In a number of influential papers, Machery, Mallon, Nichols and Stich have presented a powerful critique of so-called arguments from reference, arguments that assume that a particular theory of reference is correct in order to establish a substantive conclusion. The critique is that, due to cross-cultural variation in semantic intuitions supposedly undermining the standard methodology for theorising about reference, the assumption that a theory of reference is correct is unjustified. I argue that the many extant responses to Machery et al.’s (...) critique do little for the proponent of an argument from reference, as they do not show how to justify the problematic assumption. I then argue that it can in principle be justified by an appeal to Carnapian explication. I show how to apply the explication defence to arguments from reference given by Andreasen and by Churchland. (shrink)

Reductive externalist versions of representationalism hold that there is an externalist theory of content which is adequate for underwriting their claim that the character of experience can be reductively explained by the external physical properties represented by experience. In this paper such theories of content are shown to be inadequate, thus undermining the reductive explanation of the character of experience by the content of experience. It is argued that the character of experience is better explained non-reductively by reference to modes (...) of presentation of the properties of things. (shrink)

The experience of emotion is a fundamental part of human consciousness. Think, for example, of how different our conscious lives would be without such experiences as joy, anger, fear, disgust, pity, anxiety, and embarrassment. It is uncontroversial that these experiences typically have an intentional content. Anger, for example, is normally directed at someone or something. One may feel angry at one=s stock broker for provid- ing bad advice or angry with the cleaning lady for dropping the vase. But it is (...) not un- controversial that emotional experiences are always intentional. John Searle, for exam- ple, remarks, AMany conscious states are not Intentional, e.g., a sudden sense of elation...@. Moreover, many animals experience emotions and it is natural to sup- pose that such emotions lack the sophistication of beliefs or thoughts. When a dog ex- periences delight in seeing its master after an absence of several days, the suggestion that at least part of the dog=s experience of delight is a belief that its master has returned home seems to import into the experience something that at best is associ- ated with it and perhaps is not really a state to which the dog is subject at all. And even in the case of human beings, emotional experience often does not seem to involve thought. Consider the experience of disgust, to take one obvious example.1 Nor is a sali- ent belief required. One may have a strong fear of spiders and yet not believe that spi- ders typically pose any risk to humans. But if emotional experiences need not involve beliefs or thoughts, then just how are they intentional?2. (shrink)

According to colour irrealism, material objects do not have colour; they only appear to have colour. The appeal of this view, prominent among philosophers and scientists alike, stems in large part from the conviction that scientific explanations of colour facts do not ascribe colour to material objects. To explain why objects appear to have colour, for instance, we need only appeal to surface reflectance properties, properties of light, the neurophysiology of observers, etc. Typically attending colour irrealism is the error theory (...) of ordinary colour judgement: ordinary judgements in which colour is ascribed to a material object are, strictly speaking, false. In this paper, I claim that colour irrealists who endorse the error theory cannot explain how we acquire colour concepts (yellow, green, etc.), concepts they must acknowledge we do possess. Our basic colour concepts, I argue, could not be phenomenal concepts that we acquire by attending to the colour properties of our experience. And, I explain, all other plausible explanations render colour concepts such that our ordinary colour judgements involving them are often true. Given the explanatory considerations upon which the irrealist's position is based, this is a severe problem for colour irrealism. (shrink)

This paper proposes a subjectivist approach to color within the framework of an externalist form of representationalism about phenomenal consciousness. Motivations are presented for accepting both representationalism and color subjectivism, and an argument is offered against the case made by Michael Tye on behalf of the claim that colors are objective, physical properties of objects. In the face of the considerable difficulties associated with finding a workable realist theory of color, the alternative account of color experience set out, projectivist representationalism, (...) claims that the color properties we encounter in experience exist only in the representational contents of our experiences. Color experiences are caused by the physical structure of objects, but objects are never actually colored and color experiences systematically misrepresent objects as colored. However, despite being an error theory of color, projectivist representationalism does not do violence to our everyday use and understanding of color concepts and terms, nor does it undermine the role of color experience in aiding the perceiving subject in navigating through the world. (shrink)

The view that physical objects do not, in fact, possess colour properties is certainly the dominant position amongst scientists working on colour vision. It is also a reasonably popular view amongst philosophers. However, the recent philosophical debate about the metaphysical status of colour properties seems to have taken a more realist turn. In this article, I review the main philosophical views – eliminativism, physicalism, dispositionalism and primitivism – and describe the problems they face. I also examine how these views have (...) been classified and suggest that there may be less disparity between some of these positions than previously thought. (shrink)

The authors favor a “color realism” theory that considers colors to be physical properties residing in objects that reflect, emit, or transmit light. It is opposed to the theory that colors are sensations or visual experiences. This commentary suggests that both theories are correct, and that context usually indicates which of these dual aspects is being considered.

Vision scientists are interested in three diverse entities: physical stimuli, neural states, and consciously perceived colors, and in the mapping rules among the three. In this worldview, the three kinds of entities have coequal status, and views that attribute color exclusively to one or another of them, such as color realism, have no appeal.

In this commentary I argue that Byrne & Hilbert commit a number of philosophical solecisms: They beg the question of “realism,” they take the phenomenon and the theoretical model to be the same thing, and they surreptitiously substitute data sets for the life-world.

Byrne & Hilbert propose that color can be identified with explicit properties of physical surfaces. I argue that this claim must be qualified to take into account constraints needed to make recovery of surface color information possible. When these constraints are satisfied, then a biological visual system can establish a correspondence between perceived surface color and specific surface properties.

Byrne & Hilbert are right that it might be an objective fact that a particular tomato is unique red, but wrong that it cannot simultaneously be yellowish-red (not only objectively, but from somebody else's point of view). Sensory categorization varies among organisms, slightly among conspecifics, and sharply across taxa. There is no question of truth or falsity concerning choice of categories, only of utility and disutility. The appropriate framework for color categories is Nominalism and Pluralistic Realism.

For all animals, color is an indicator of the substance and state of objects, for which purpose reflectance is just one among many relevant optical properties. This broader meaning of color is confirmed by linguistic evidence. Rather than reducing color to a simple physical property, it is more realistic to embrace its full phenomenology.

We make three points. First, the concept of productance value that the authors propose in their defense of color physicalism fails to do the work for which it is intended. Second, the authors fail to offer an adequate physicalist account of what they call the hue-magnitudes. Third, their answer to the problem of individual differences faces serious difficulties.

Colors are sensible qualities. They are qualities that objects are perceived to have. Thus, when Norm, a normal perceiver, perceives a blue bead, the bead is perceived have a certain quality, perceived blueness. `Quality', here, is no mere synonym for property; rather, a quality is a kind of property a qualitative, as opposed to quan• titative, property. (The quantitative is a way of contrasting with the qualitative perhaps not the only way.).

Our perceptual systems make information about the world available to our cognitive faculties. We come to think about the colors and shapes of objects because we are built somehow to register the instantiation of these properties around us. Just how we register the presence of properties and come to think about them is one of the central problems with understanding perceptual cognition. Another problem in the philosophy of perception concerns the nature of the properties whose presence we register. Among the (...) perceptible properties are colors and shapes, for example, and there is a long philosophical tradition of drawing and refusing to draw metaphysical distinctions between them. This paper makes a claim about the information-theoretic approach to perceptual cognition in order to argue for a fundamentally epistemological distinction between colors and shapes. What makes shapes and colors seem so different to us is how we carry information about their presence around us. In particular, we can come to know more about the shapes on the basis of perceiving them than we can come to know about the colors. One interesting feature of how this distinction is drawn is that it partially vindicates Locke’s claim that our ideas of primary qualities like shapes resemble them in ways our ideas of colors do not. (shrink)

In this paper I shall defend a projectivist view of sensory experience. The case I shall focus on is that of color experience. Projectivism has recently been criticized by some authors who claim that it is unintelligible, or at least implausible, and that it makes a severe category mistake. I shall argue that despite some prima facie impressions of implausibility, projectivism can be made intelligible, and plausible, if its details are spelled out in a reasonable way. In addition, projectivism is (...) ubiquitous in human psychology, and certain cases of projection are reasonably viewed as making a category mistake. Viewed from this perspective, sensory projection is just one instance of projectivism, brought about by low-level perceptual processing. Whether sensory projection is one that makes a category mistake is not obvious. However, even if it does, this is perfectly compatible with the evolutionary advantage of sensation and perception. (shrink)

Revelation, the thesis that the full intrinsic nature of colors is revealed to us by color experiences, is false in Byrne & Hilbert's (B&H's) view, but in an interesting and nonobvious way. I show what would make Revelation true, given B&H's account of colors, and then show why that situation fails to obtain, and why that is interesting.

Metamerism is a rather common feature of objects. The authors see it as problematic because they are concerned with a special case: metamerism in standard conditions. Such metamerism does not, however, pose a problem for color realists. There is an apparent problem in cases of metameric light sources, but to see such metamers as problematic is to fail to answer Berkeley's challenge.

A traditional explanation that dates back to Aristotle is that we access color in one perceptual modality only, whereas shape we perceive via two different modalities: visual and tactile. Two independent modalities make possible a verification of our percepts which is not possible for qualities accessed in one modality only.

Visual percepts are called veridical when a “real” object can be identified as their cause, and illusions otherwise. The perceived position and color of a flashed object may be called veridical or illusory depending on which viewpoint one adopts. Since “reality” is assumed to be fixed (independent of viewpoint) in the definition of veridicality (or illusion), this suggests that “perceived” position and color are not properties of “real” objects.