Online research in philosophy

Color subjectivism is the view that color properties are mental properties of our visual sensations, perhaps identical with properties of neural states, and that nothing except visual sensations and other mental states exhibits color properties. Color phys- icalism, by contrast, holds that colors are exclusively properties of visible physical objects and processes.

Most objectivist and dispositionalist theories of color have tried to resolve the challenge raised by color variations by drawing a distinction between real and apparent colors. This paper considers such a strategy to be fundamentally erroneous. The high degree of variability of colors constitutes a crucial feature of colors and color perception; it cannot be avoided without leaving aside the real nature of color. The objectivist theory of color defended in this paper holds that objects have locally many different objective colors. Most color variations are then real and result from the extreme richness of color properties.

This book is a major contribution to the interdisciplinary project of investigating the true nature of color vision. In recent times, research into color vision has been one of the main success stories of cognitive science. Each discipline in the field--neuroscience, psychology, linguistics, computer science and philosophy--has contributed significantly to our understanding of color. Evan Thompson provides an accessible review of current scientific and philosophical discussions of color vision. He steers a course between the subjective and objective positions on color, arguing for a relational account. Thompson develops a novel "ecological" approach to color vision in cognitive science and the philosophy of perception. The book is vital reading for all cognitive scientists and philosophers whose interests touch upon this central area.

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.

The perceptual circularity demonstrated by R. Shepard with respect to hue turns out to be a sphericity of color perception based on color excitation vectors of neuronal level. The spherical color model implicitly contains information concerning generalization under color learning. Subjective color differences are “computed” in neuronal nets being represented by amplitudes of evoked potentials triggered by color change. [Shepard].

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.

Let me begin by indicating where I think Harman and I are in agreement. We both think that "subjective reactions" must come into an account of color, although we have different views about how they do. We both think that perceptual experience has a "presentational or representational character," and that color is represented by our visual experiences as a feature of external objects, not as a feature of our experience. Moreover, we agree that, as Harman puts it, "color is experienced as a simple basic quality, rather than a disposition or complex of causal properties." As Harman emphasized in an earlier paper, 1 what we are introspectively aware of in our experience is its presentational or representational content, not any "mental paint" which bestows this content. I shall refer to all of this as Harman's "phenomenological point." Because we agree on this, we also agree that if his characters George and Mary were spectrum inverted relative to each other, supposing that to be possible, this would have to involve their perceiving the same objects as having different properties, this despite the fact that as normal perceivers they would perceive these objects as having the same colors. And I think we agree that in this case the properties would have to be relational ones, defined or constituted by their relations to the experiences of the subject perceiving them.

In “The Location Problem for Color Subjectivism,” Peter Ross argues against what he calls subjectivism — the view that “colors are not describable in physical terms, ... [but are] mental processes or events of visual states” (2),¹ and in favor of physicalism — a view according to which colors are “physical properties of physical objects, such as reflectance properties” (10). He rejects an argument that has been offered in support of subjectivism, and argues that, since no form of subjectivism is able to account for our perception of color, we are better off adopting physicalism.

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.

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.