It is plausible to think that some animals perceive the world as coloreddifferently from the way humans perceive it. I argue that the best way ofaccommodating this fact is to adopt perceiver-relativism, the view that colorpredicates express relations between objects and types of perceivers.Perceiver-relativism makes no claim as to the identity of color properties;it is compatible with both physicalism and dispositionalism. I arguehowever for a response-dependence version of it according to which an object counts as red (for a type of (...) perceiver) iff it standardly looks red to normal perceivers (of that type). Finally, I develop a notion of minimal realism on which this account counts as realist despite its subjectivist elements, in that it is committed to the objectivityof truth. (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)

C. L. Hardin has argued that the colour opponency of the vision system leads to chromatic subjectivism: chromatic sensory states reduce to neurophysiological states. Much of the force of Hardin's argument derives from a critique of chromatic objectivism. On this view chromatic sensory states are held to reduce to an external property. While I agree with Hardin's critique of objectivism it is far from clear that the problems which beset objectivism do not apply to the subjectivist position as well. I (...) develop a critique of subjectivism that parallels Hardin's antiobjectivist argument. (shrink)

Timothy Williamson’s Knowledge and its Limits has been highly influential since the beginning of this century. It can be read as a systematic response to scepticism. One of the most important notions in this response is the notion of «evidence,» which will be the focus of the present paper. I attempt to show primarily two things. First, the notion of evidence invoked by Williamson does not address the sceptical worry: he stipulates an objective notion of evidence, but this begs the (...) question against his opponent. Second, his related thesis «Evidence equals Knowledge» does not sit well with his own content externalism: he promises to relate epistemology to philosophy of mind, but he fails to live up to this commitment in his crucial chapter on scepticism. Other minor problems concerning evidence will also be discussed in due course. (shrink)

In this paper, I propose a fictionalist approach to the problem of color. On my view, which I call prescriptive color fictionalism, we can continue to employ our color discourse as we have thus far even if it turns out that there are no colored objects. My proposal is a species of error theory. As such, it does not describe our current practices. It is rather proposed as a prescription to a problem, namely that the color theory we accept (according (...) to which there are colored objects) is false. By formulating a fictionalist account of color and showing that we can preserve ordinary color discourse in the absence of colored objects, I provide a solution to the problem of color. (shrink)

Philosophers have long sought to explain perceptual constancy—the fact that objects appear to remain the same color, size and shape despite changes in the illumination condition, perspective and the relative distance—in terms of a mechanism that actively categorizes variable stimuli under the same pre-formed conceptual categories. Contemporary representationalists, on the other hand, explain perceptual constancy in terms of a modular mechanism that automatically discounts variation in the visual field to represent the stable properties of objects. In this paper I argue (...) that while the former view is unmotivated by empirical evidence, the later fails to account for inter- and intra-personal variability, the influence of expectations on constancy, and the systematic and normal failures of color constancy. A Bayesian approach that builds on the representational tradition in psychology solves both problems. (shrink)

As demonstrated by several example displays, color illusions challenge color realism, because they involve a one-to-many reflectance-to-color mapping. Solving this problem by differentiating between veridical and illusory colors corresponding to the same reflectance is hampered because of the lack of an appropriate criterion. However, the difference between veridical and illusory color perception can still be maintained.

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 conceive of color perception as the representation of a physical property “out there.” In our view, their approach does not only have various internal problems, but is also apt to becloud both the intricate and still poorly understood role that “ color ” plays within perceptual architecture, and the complex coupling to the “external world” of the perceptual system as an entirety. We propose an alternative perspective, which avoids B&H's misleading dichotomy between a purely subjective and a (...) realist conception of “ color.”. (shrink)

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.

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)

Despite a wealth of data we still have no clear idea what color experiences represent. In fact, color experiences vary with so many factors that it has been claimed that they do not represent anything at all. The primary challenge for any representational account of color experience is to accommodate the various psychophysical results that demonstrate that color appearance depends not only on the spectral nature of the target but also on the spectral, spatial and figural nature of the surround. (...) A number of theorists have proposed that this dependence is an aspect of the visual system's constancy mechanism. However this does not in and of itself tell us what, if anything, is represented in color experience. Ultimately the answer to this question will be informed by one's theory of representational content. I will argue that adopting a molecular scheme of representation enables the development of an account of the represented object of color experience that can do justice to the psychophysical data. (shrink)

Inter-species variation in colour perception poses a serious problem for the view that colours are mind-independent properties. Given that colour perception varies so drastically across species, which species perceives colours as they really are? In this paper, I argue that all do. Specifically, I argue that members of different species perceive properties that are determinates of different, mutually compatible, determinables. This is an instance of a general selectionist strategy for dealing with cases of perceptual variation. According to selectionist views, objects (...) simultaneously instantiate a plurality of colours, all of them genuinely mind-independent, and subjects select from amongst this plurality which colours they perceive. I contrast selectionist views with relationalist views that deny the mind-independence of colour, and consider some general objections to this strategy. (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.

Frank Jackson and Robert Pargetter (1987)2 have argued for a version of reductive physicalism about color which they claim can accommodate the basic intuitions that have led others to embrace dispositionalism or subjectivism about color. Jackson (1996) has further developed the view and provided responses to some objections to its original statement. While Jackson and Pargetter do not have much company in endorsing their specific form of color physicalism, elements of their view have shown up in other realist accounts, including (...) the relativized account of color offered by John Spackman (2002), the disjunctivism of color properties endorsed by Peter Ross (2000), and the subjectivist strain present in Sydney Shoemaker’s (1994) discussion of color.3 Additionally, Mark Johnston (1992) has used Jackson and Pargetter’s view as a principal target in his arguments against color physicalism. (shrink)

B&H understate the difficulties facing their version of color realism. We doubt that they can fix reflectance types and magnitudes in a way that does not invoke relations to perceivers. B&HÂ’s account therefore resembles the dispositional or ecological accounts that they dismiss. This is a good thing, for a dispositional account is promising if understood in an ecological framework.

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)

University of Connecticut Storrs, CT 06279-2054. Recent versions of objectivism can reply to the argument from metamers. The deeper rift between subjectivists and objectivists lies in the question of how to explain the structure of qualitative similarities among the colors. Subjectivism grounded in this fashion can answer the circularity objection raised by Dedrick. It endorses skepticism about the claim that there is some one property of objects that it is the function of color vision to detect. Color vision may enable (...) us to detect differences in spectral composition without granting us the capacity to detect identities. (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.

b>. Computational models of colour vision assume that the biological function of colour vision is to detect surface reflectance. Some philosophers invoke these models as a basis for 'externalism' about perceptual content (content is distal) and 'objectivism' about colour (colour is surface reflectance). In an earlier article (Thompson et al. 1992), I criticized the 'computational objectivist' position on the basis of comparative colour vision: There are fundmental differences among the colour vision of animals and these differences do not converge on (...) the detection of any single type of environmental property. David R. Hilbert (1992) has recently defended computational objectivism against my 'comparative argument;' his arguments are based on the externalist approach to perceptual content originally developed by Mohan Matthen (1988) and on the computationally inspired theory of the evolutionary basis for trichromacy developed by Roger N. Shepard (1990). The present article provides a reply to Hilbert with extensive criticism of both Matthen's and Shepard's theories. I argue that the biological function of colour vision is not to detect surface reflectance, but to provide a set of perceptual categories that can apply to objects in a stable way in a variety of conditions. Comparative research indicates that both the perceptual categories and the distal stimuli will differ according to the animal and its visual ecology; therefore externalism and objectivism must be rejected. (shrink)

I propose a counterexample to naturalistic representational theories of phenomenal character. The counterexample is generated by experiences of novel colours reported by Crane and Piantanida. I consider various replies that a representationalist might make, including whether novel colours could be possible colours of objects and whether one can account for novel colours as one would account for binary colours or colour mixtures. I argue that none of these strategies is successful and therefore that one cannot fully explain the nature of (...) the phenomenal character of perceptual experiences using a naturalistic conception of representation. (shrink)

This thesis is an examination and critique of naturalistic representational theories of phenomenal character. Phenomenal character refers to the distinctive quality that perceptual and sensational experiences seem to have; it is identified with 'what it is like' to undergo experiences. The central claims of representationalism are that phenomenal character is identical with the content of experience and that all representational states, bearing appropriate relations to the cognitive system, are conscious experiences. These claims are taken to explain both how conscious experiential (...) states arise and their nature. After examining the desiderata for naturalistic explanations, I argue that theories which ascribe nonconceptual content to experiences are the most plausible versions of representationalism. Further, causal covariation and teleological theories yield distinctive and interesting representationalist positions, hence, they become the focus of this study. To assess representationalism, I investigate whether all differences in phenomenal character can be correlated with differences in content. I claim that a useful distinction can be drawn between implicit and explicit content, which allows one to best describe the phenomena of perfect and relative pitch. I then argue that ambiguous figures show that two experiences can have the same content but different phenomenal character. I explicate the Inverted Earth hypothesis and claim that to identify content and phenomenal character, representationalists either have to condone the possibility of philosophical zombies, or hold that people lack authoritative first-person knowledge of their current experiences. Both these positions are unpalatable. Finally, I argue that representationalists cannot ascribe contents to experiences of novel colours to account for their phenomenal character. I also question, in light of dissociation phenomena, whether there is one distinctive relationship that all experiences bear to the cognitive system. I conclude that phenomenal character cannot be identical with the type of content under investigation, and that naturalistic representationalist theories cannot fully explain conscious experience. (shrink)

Frank Jackson champions the cause of conceptual analysis as central to philosophical inquiry. In recent years conceptual analysis has been undervalued and widely misunderstood, suggests Jackson. He argues that such analysis is mistakenly clouded in mystery, preventing a whole range of important questions from being productively addressed. He anchors his argument in discussions of specific philosophical issues, starting with the metaphysical doctrine of physicalism and moving on, via free will, meaning, personal identity, motion, and change, to ethics and the philosophy (...) of color. In this way the book not only offers a methodological program for philosophy, but also casts new light on some much-debated problems and their interrelations. (shrink)

What we observe, through our usually limited lens, is that differential growing of space determines forms -characterized by their shape, size and coloration. As non-Euclidean geometrical mathematics have proclaimed: forms are manifestations of the curvature of space. Physics and other natural laws impose mathematical structural restrictions to biological forms. The molecules comprising any living form become arranged in specific ways in response to physical forces as well as chemical and biochemical conditions. Over time, such forms inherit additional historical restrictions that (...) make up their meaning, their semiotics. Color does not escape from this orthogenic reality. In this study, we present the colored pattern of the connexivum of Triatoma maculata, an insect vector of the etiologic agent of Chagas disease. This model is used as an example to appreciate mimicry under a heterodox and provocative approach. We unveil that beyond 1) mathematical and 2) historical semiotic restrictions of T. maculata mimesis of a yellowish-black alternating pattern, there are also 3) artistic interpretations; where metaphysics of life, beyond human perspective, is included. (shrink)

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.

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.

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.

Reflectance and spectral power functions are poor predictors of color experiences. Only in completely relativized conditions (single observer, non-metameric set of stimuli, and single set of viewing conditions) is the relationship close. Variation in reflectance of Munsell chips experienced by color-normal observers as having a unique green hue encompasses approximately sixty percent of the complete range of hues falling under the category “green”; and in recent determinations of unique hues, ranges of yellow and green as well as green and blue (...) unique hues overlap. (shrink)

There are 2,000 hair cells in the cochlea, but only three cones in the retina. This disparity can be understood in terms of the differences between the physical characteristics of the auditory signal (discrete excitations and resonances requiring many narrowly tuned receptors) and those of the visual signal (smooth daylight excitations and reflectances requiring only a few broadly tuned receptors). We argue that this match supports the physicalism of color and timbre.

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 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?

According to color subjectivism, colors are mental properties, processes, or events of visual experiences of color. I first lay out an argument for subjectivism founded on claims from visual science and show that it also relies on a philosophical assumption. I then argue that subjectivism is untenable because this view cannot provide a plausible account of color perception. I describe three versions of subjectivism, each of which combines subjectivism with a theory of perception, namely sense datum theory, adverbialism, and the (...) virtual color proposal, and argue that each version faces serious objections. Considering these three theories of perception to be exhaustive of those available to the subjectivist, I conclude that subjectivism is untenable and that the scientifically motivated argument for this view is unsound. I then offer the diagnosis that the philosophical assumption on which this argument relies is mistaken. (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)

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

A survey of color science and color vision.

Colour vision plays a foundational explanatory role in the philosophy of colour, and serves as perennial quarry in the wider philosophy of perception. I present two contributions to our understanding of this notion. The first is to develop a constitutive approach to characterizing colour vision. This approach seeks to comprehend the nature of colour vision qua psychological kind, as contrasted with traditional experiential approaches, which prioritize descriptions of our ordinary visual experience of colour. The second contribution is to argue that (...) colour vision does not constitutively involve the ability to see colours, in a natural and categorically committed sense. I argue that two subjects exactly alike in respect of their constitutive colour vision abilities could differ in respect of whether or not they have categorical perception of colour. The argument is supported by thought experiment and dissociations observed in cognitive neuropsychology. The argument also bears connections to recent neo-Whorfian accounts of colour categorization. _1._ Introduction _2._ Colour Vision, Experience, and Natures _3._ The Central Argument _3.1._ Colour constancy and discrimination _3.2._ Dissociating colour vision and categorical perception for colour _4._ Whorf and the View from Cognitive Neuropsychology _5._ Conclusion. (shrink)

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)

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.

The primary issues concern whether objects have colours, and what sorts of properties the colours are. Some philosophers hold that nothing is coloured, others that colour are powers to affect perceivers, and others that colours are physical properties.

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)

Dennett has maintained that a careful examination of our intuitive notion of qualia reveals that it is a confused notion, that it is advisable to accept that experience does not have the properties designated by it and that it is best to eliminate it. Because most scientists share this notion of qualia, the major line of attack of his project becomes that of raising objections against the ability of science to answer some basic questions about qualia. I try to show (...) that science appeals to qualia and that it in fact adheres to a notion of qualia different from the one that Dennett has attributed to it. It is argued that qualia are amenable to scientific investigation and that this is the reason why science contributes toward the clarification of the notion of qualia. I also try to show that Dennett's skepticism about the abilities of science in answering questions posited by one of his thought experiments is unwarranted. I conclude that we need not accept Dennett's eliminativism about qualia. (shrink)

Because our only access to color qualities is through their appearance, Byrne & Hilbert's insistence on a strict distinction between apparent colors and real colors leaves them without a principled way of determining when, if ever, we see colors as they really are.

Byrne & Hilbert's thesis, that color be associated with reflectance-type, is questioned on the grounds that it is far from clear that the human visual system is able to determine a surface's reflectance-type with sufficient accuracy. In addition, a (friendly) suggestion is made as to how to amend the definition of reflectance-type in terms of CIE (Commission Internationale de l'Eclairage) coordinates under a canonical illuminant.

I argue that Byrne & Hilbert (B&H) have not answered Hardin's objection to physicalism about color concerning the unitary-binary structure of the colors for two reasons. First, their account of unitary-binary structure seems unsatisfactory. Second, pace B&H, there are no physicalistically acceptable candidates to be the hue-magnitudes. I conclude with a question about the justification of physicalism about color.

The reflectance types that Byrne & Hilbert identify with colors count as types only in a way that is more dependent on, and more relative to color perceivers, than their account suggests. Their account of perceptual content may be overly focused on input conditions and distal causes.

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.

“The problem of color realism” as defined in the first section of the target article, is crucial to the argument laid out by Byrne & Hilbert. They claim that the problem of color realism “does not concern, at least in the first instance, color language or color concepts” (sect. 1.1). I argue that this claim is misconceived and that a different characterisation of the problem, and some of their preliminary assumptions makes their positive proposal less appealing.

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.