Where are we to look for the unique hues? Out in the world? In the eye? In more central processing? 1. There are difficulties looking for the structure of the unique hues in simple combinations of cone-response functions like ( L − M ) and ( S − ( L + M )): such functions may fit pretty well the early physiological processing, but they don’t correspond to the structure of unique hues. It may seem more promising to look to, (...) e.g., Hurvich & Jameson’s ‘chromatic response functions’; but these report on psychophysical behaviour, not on underlying physiology. So ‘opponent processing’ isn’t any particular help on the unique hues—and even physiology in general seems not to have come up with any good correlate or explanation. 2. Wright ( Review of Philosophy and Psychology 2: 1–17, 2011 ) looks in a different place: to (a) magnitude of total visual response that a stimulus light provokes, the maxima and minima of which, he thinks, give us the boundaries of the main hue categories (Wright connects these with Thornton’s ‘prime’ and ‘antiprime’ colours in an illuminant: Journal of the Optical Society of America 61 ( 1971 ): 1155–1163); and (b) the ratio of chromatic to achromatic response, the maxima and minima of which, he suggests, give us the focal points of the unique hues. The suggestions are extremely interesting; but the desired correspondences have some counterexamples; and where they hold, one could wonder how much they depend upon the particular choice of functions to measure (a) and (b); and one could hope for more of an explanatory linkage between the sets of items in question. 3. Could the unique hues come from, so to speak, the external world? White and black can easily be defined as particular kinds of reflectance. What of the standard four unique hues? Variation in kinds of sunlight and skylight coincides well with variation along a line from unique yellow to unique blue (cf. Shepard 1992 , Mollon 2006 ). If we wanted something to calibrate our standards for unique yellow and blue as the lens of the eye changes with age, and despite interpersonal cone differences, this would be a good basis—and there are several ways this can be extended to surface colours. But is there any essential connection between these things: is there any rationale why the light of the sun and the sky should be counted as unique hued ? An answer may be: because in our environment, these illuminants are as close to white (or the natural illuminant colour) as you can get—to see things tinged with sunlight or skylight should be to see them minimally tinged with any alien colour. Whereas other hues in an illuminant would be treated as tinging with a more alien colour the thing seen. (shrink)

Colors are of philosophical interest for two kinds of reason. One is that colors comprise such a large and important portion of our social, personal and epistemological lives and so a philosophical account of our concepts of color is highly desirable. The second reason is that trying to fit colors into accounts of metaphysics, epistemology and science leads to philosophical problems that are intriguing and hard to resolve. Not surprisingly, these two kinds of reasons are related. The fact that colors (...) are so significant in their own right, makes more pressing the philosophical problems of fitting them into more general metaphysical and epistemological frameworks. (shrink)

Quite a few cognitive scientists are working toward a naturalization of phenomenology. Looking more closely at the relevant literature, however, the ‘naturalizing phenomenology’ proposals show the presence of different conceptions, assumptions, and formalisms, further differentiated by different philosophical and/or scientific concerns. This paper shows that the original Husserlian stance is deeper, clearer and more advanced than most supposed contemporary improvements. The recent achievements of experimental phenomenology show how to ‘naturalize’ phenomenology without destroying the guiding assumptions of phenomenology. The requirements grounding (...) the scientific explanation of subjective experience are discussed, such as the nature of the stimuli, their variables, and their manipulation by properly phenomenological methods. (shrink)

Hardin’s empirically-grounded argument for color eliminativism has defined the color realism debate for the last 30 years. By Hardin’s own estimation, phenomenal structure—the unique/binary hue distinction in particular—poses the greatest problem for color realism. Examination of relevant empirical findings shows that claims about the unique hues which play a central role in the argument from phenomenal structure should be rejected. Chiefly, contrary to widespread belief amongst philosophers and scientists, the unique hues do not play a fundamental role in determining all (...) color appearances. Among the consequences of this result is that greater attention should be paid to certain proposals for putting the structure of phenomenal color into principled correspondence with surface reflectance properties. While color realism is not fully vindicated, it has much greater empirical plausibility than previously thought. (shrink)

The paper presents color as a case study for the analysis of phenomena that pertain to several levels of reality and are typically framed by different sciences and disciplines. Color, in fact, is studied by physics, biology, phenomenology, and esthetics, among others. Our thesis is that color is a different entity for each level of reality, and that for this reason color generates different observables in the epistemologies of the different sciences. By analyzing color as a paradigmatic case of an (...) entity naturally spreading over different levels of reality, the paper raises the question as to whether making explicit the usually implicit ontological assumptions embedded within the different observables exploited by the different sciences may eventually clarify some of the difficulties of developing a comprehensive theory of color. (shrink)

This paper argues that the distinctiveness of the Hering primary hues—red, green, blue, and yellow—is already evident at the retina. Basic features of spectral sensitivity provide a foundation for the development of unique hue perceptions and the hue categories of which they are focal examples. Of particular importance are locations in color space at which points of minimal and maximal spectral sensitivity and extreme ratios of chromatic to achromatic response occur. This account builds on Jameson and D’Andrade’s (1997) insight about (...) the relationship between the Hering primaries and chromatic/achromatic ratios, Romney and Chiao’s (2009) color appearance model, and Thornton’s (1971, 1999) research on artificial lighting. (shrink)