Color

No crucial experiment demonstrates that four hue categories are needed to describe color appearance. Instead, converging lines of evidence suggest that the terms red, yellow, green, and blue are sufficient and precise enough for deriving color discrimination functions and for a useful model constraining relations between color appearance and neuronal responses. Such a model need not be based on linguistic universals. Until something better is available, this holds.

In On the Genealogy of Color , Zed Adams challenges widely held philosophical views about the nature of color, exploring the relevance of the history of color science for contemporary debates in color realism/anti-realism and philosophy of mind. Adams argues that the two sides of the contemporary debate on the problem of color realism, Cartesian anti-realism and Oxford realism, are both predicated on an assumption that the concept of color perception is ahistorical and unrevisable. Adams takes issue with this premise (...) and traces the development of theories of color in order to undermine this assumption and open up the conversation about our perception of color. This book makes a significant contribution to recent debates on philosophical methodology by demonstrating the efficacy of using the genealogical method to explore philosophical concepts, and will appeal to philosophers of perception, philosophers of mind, and metaphysicians. (shrink)

Al-Kindi was influenced by two Greek traditions in his attempts to explain vision, light and color. Most obviously, his works on optics are indebted to Euclid and, perhaps indirectly, to Ptolemy. But he also knew some works from the Aristotelian tradition that touch on the nature of color and vision. Al-Kindi explicitly rejects the Aristotelian account of vision in his De Aspectibus, and adopts a theory according to which we see by means of a visual ray emitted from the eye. (...) But in the same work, al-Kindi draws on Philoponus. (shrink)

A common view in both philosophy and the vision sciences is that, in human vision, wavelength information is primarily ‘for’ colouring: for seeing surfaces and various media as having colours. In this article we examine this assumption of ‘colour-for-colouring’. To motivate the need for an alternative theory, we begin with three major puzzles from neurophysiology, puzzles that are not explained by the standard theory. We then ask about the role of wavelength information in vision writ large. How might wavelength information (...) be used by any monochromat or dichromat and, finally, by a trichromatic primate with object vision? We suggest that there is no single ‘advantage’ to trichromaticity but a multiplicity, only one of which is the ability to see surfaces and so on as having categorical colours. Instead, the human trichromatic retina exemplifies a scheme for a general encoding of wavelength information given the constraints imposed by high spatial resolution object vision. Chromatic vision, like its partner, luminance vision, is primarily for seeing. Viewed this way, the ‘puzzles’ presented at the outset make perfect sense. 1 Reframing the Problem1.1 Introduction1.2 Three puzzles1.2.1 Why is trichromatic vision an anomaly in diurnal mammals?1.2.2 Why does the colour system occupy such a large and central part in human vision?1.2.3 Why are the blue cones so rare?1.3 Recasting the question2 The Costs and Benefits of Spectral Vision2.1 Spectral information and object vision2.2 Encoding the spectral dimension of light2.2.1 ‘General’ versus ‘specific’ encoding2.2.2 Spectral encoding and the monochromat2.2.3 Spectral encoding and the dichromat2.2.4 Spectral encoding and the human trichromat2.3 Three puzzles revisited2.3.1 Why is trichromatic vision an anomaly in diurnal mammals?2.3.2 Why does the colour system occupy such a large and central part in human vision?2.3.3 Why are the blue cones so rare3 Conclusion. (shrink)

Colours appear to instantiate a number of structural properties: for instance, they stand in distinctive relations of similarity and difference, and admit of a fundamental distinction into unique and binary. Accounting for these structural properties is often taken to present a serious problem for physicalist theories of colour. This paper argues that a prominent attempt by Byrne and Hilbert to account for the structural properties of the colours, consistent with the claim that colours are types of surface spectral reflectance, is (...) unsuccessful. Instead, it is suggested that a better account of the structural properties of the colours is provided by a form of non-reductive physicalism about colour: a naïve realist theory of colour, according to which colours are superficial mind-independent properties. (shrink)

This paper considers two accounts of the way that colours are represented in perception, thought, and language that are consistent with relationalist theories of colour: Jonathan Cohen’s contextualist semantics for colour ascriptions, and Andy Egan’s suggestion that colour ascriptions have self-locating contents. I argue that colours are not represented in perception, thought, or language as mind-dependent relational properties.

This essay deals with the problem of the status of colours, traditionally considered as the paradigmatic case of secondary qualities: do colours exist only as aspects of experience or are they real properties of objects, existing independently of human and animal perception? Recently, John Campbell has argued in favour of the simple view of colours, according to which colours are real properties of objects. I discuss the place of Campbell's position in a debated which was started by John Mackie and (...) continued by John McDowell, and defend it from a criticism due to Michael Smith. I conclude that the simple view is a philosophically credible position. Subsequently, I consider an alleged contradiction between the simple view and semantic externalism pointed out by Jim Edwards. I suggest that a supporter of the simple view may consistently maintain semantic externalism, if she also accepts epistemological externalism about the canonical warrant of perceptual judgements. (shrink)

This essay deals with the problem of the status of colours, traditionally considered as the paradigmatic case of secondary qualities: do colours exist only as aspects of experience or are they real properties of objects, existing independently of human and animal perception? Recently, John Campbell has argued in favour of the simple view of colours, according to which colours are real properties of objects. I discuss the place of Campbell's position in a debated which was started by John Mackie and (...) continued by John McDowell, and defend it from a criticism due to Michael Smith. I conclude that the simple view is a philosophically credible position. Subsequently, I consider an alleged contradiction between the simple view and semantic externalism pointed out by Jim Edwards. I suggest that a supporter of the simple view may consistently maintain semantic externalism, if she also accepts epistemological externalism about the canonical warrant of perceptual judgements. (shrink)

This book comprises material on colour which was written by Wittgenstein in the last eighteen months of his life. It is one of the few documents which shows him concentratedly at work on a single philosophical issue. The principal theme is the features of different colours, of different kinds of colour and of luminosity—a theme which Wittgenstein treats in such a way as to destroy the traditional idea that colour is a simple and logically uniform kind of thing. This edition (...) consists of Wittgenstein's basic German text, together with an English translation. (shrink)

This book comprises material on colour which was written by Wittgenstein in the last eighteen months of his life. It is one of the few documents which shows him concentratedly at work on a single philosophical issue. The principal theme is the features of different colours, of different kinds of colour and of luminosity—a theme which Wittgenstein treats in such a way as to destroy the traditional idea that colour is a simple and logically uniform kind of thing. This edition (...) consists of Wittgenstein's basic German text, together with an English translation. (shrink)

Observers matched patches (simulated Munsell papers) in two simultaneously presented computer-controlled displays, a standard array presented under 6500-K illumination and a test array under 4000 or 10,000 K. Adaptation to the test illuminants was limited. The adjusted patch was surrounded by a single color (annulus display) or by many colors (Mondrian display). Observers either matched hue and saturation or made surface-color (paper) matches in which the subject was asked to make the test patch look as if it were cut from (...) the same piece of paper as the standard patch. For two of the three subjects, the paper matches were approximately color constant. The hue- saturation matches showed little color constancy. Moreover, the illumination difference between the two displays was always visible. Our data show that simultaneous mechanisms alone (e.g., simultaneous color contrast) alter hues and saturations too little to produce hue constancy. (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)

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.

Objectivism and projectivism are standardly taken to be incompatible theories of color. Here we argue that this incompatibility is only apparent: objectivism and projectivism, properly articulated so as to deal with basic objections, are in fundamental agreement about the ontology of color and the phenomenology of color perception.