Online research in philosophy

An adequate ontology of color must face the empirical facts about per- ceptual variation. In this paper I begin by reviewing a range of data about perceptual variation, and showing how they tell against color physicalism and motivate color relationalism. Next I consider a series of objections to the argument from perceptual variation, and argue that they are un- persuasive. My conclusion will be that the argument remains a powerful obstacle for color physicalism, and a powerful reason to believe in color relationalism instead.

In this paper I argue that color is a relational feature of the distal objects of perception, a way of appearing. I begin by outlining three constraints any theory of color should satisfy: (i) physicalism about the non-mental world, (ii) consistency with what is known from color science, and (iii) transparency about color experience. Traditional positions on the ontological status of color, such as physicalist reduction of color to spectral re?ectance, subjectivism, dispositional- ism, and primitivism, fail, I claim, to meet all three constraints. By treating color as a relational property, a way of appearing, the three constraints can be met. However, serious problems for this view emerge when considering the relation between illusory color experiences (particularly hallucinations) and veridical color experiences. I do not propose a solution to these problems.

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.

Color relationalism is the view that colors are constituted in terms of relations between subjects and objects. The most historically important form of color relationalism is the classic dispositionalist view according to which, for example red is the disposition to look red to standard observers in standard conditions (mutatis mutandis for other colors).1 However, it has become increasingly apparent in recent years that a commitment to the relationality of colors bears interest that goes beyond dispositionalism (Cohen, 2004; Matthen, 1999, 2001, 2005; Thompson, 1995). Accordingly, it is an important project for those interested in the metaphysics of color to sort through and assess different forms of color relationalism. There is, however, a powerful and general cluster of objections that has been thought by many to amount to a decisive refutation of any and all forms of color relationalism. Although this idea has been developed in a number of ways, the basic thought is that relationalism — qua theory of color — is at odds with the manifest evidence of color phenomenology, and that this clash between theory and data should be resolved by giving up the theory.

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.

When we open our eyes, the world seems full of colored opaque objects, light sources, and transparent volumes. One historically popular view, _eliminativism_, is that the world is not in this respect as it appears to be: nothing has any color. Color _realism_, the denial of eliminativism, comes in three mutually exclusive varieties, which may be taken to exhaust the space of plausible realist theories. Acccording to _dispositionalism_, colors are _psychological_ dispositions: dispositions to produce certain kinds of visual experiences. According to both _primitivism_ and _physicalism_, colors are not psychological dispositions; they differ in that primitivism says that no reductive analysis of the colors is possible, whereas physicalism says that they are physical properties. This paper is a defense of physicalism about color.

What is the relationship between color experience and color? Here, I defend the view that it is semantic: color experience denotes color in a code innately known by the perceiver. This semantic theory contrasts with a variety of theories according to which color is defined as the cause of color experience (in a special set of circumstances). It also contrasts with primary quality theories of color, which treat color as a physical quantity. I argue that the semantic theory better accounts for the kinds of knowledge we have regarding both the color of objects that we see and of the colors themselves.

In this paper I argue that all transparent objects are colorless. This thesis is important for at least three reasons. First, if transparent objects are colorless, there is no need to distinguish between colors which characterize three-dimensional bodies, like transparent colors, and colors which lie on the surface of objects. Second, traditional objections against color physicalism relying on transparent colors are rendered moot. Finally, an improved understanding of the relations between colors, light and transparency is provided.

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.

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.