On the Structural Properties of the Colors∗

Primary quality theories of color claim that colors are intrinsic, objective, mind-independent properties of external objects — that colors, like size and shape, are examples of the sort of properties moderns such as Boyle and Locke called primary qualities of body. Primary quality theories have long been seen as one of the main philosophical options for understanding the nature of color. However, a recent, empirically motivated argument seems to have convinced many that primary quality theories cannot be sustained. This argument, in outline, alleges that colors bear structural relations to each other that no primary qualities bear to each other, and therefore that colors cannot be primary qualities. This argument has received considerable philosophical attention in recent years, and appears to have convinced many to abandon primary quality theories of color. However, I believe the argument has been misunderstood. In this paper I shall examine arguments based on the structural properties of the colors in order to discern what they do and do not show about primary quality theories of color. I’ll begin by reviewing the empirical data concerning structural properties of the colors and then showing how these data have been used to argue against primary quality theories of color (§1). Then, after looking at some unsatisfactory responses to this argument (§2), I’ll offer another response (§§3–5) that, it seems ∗Revision : 1.9. †Department of Philosophy, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0119, [email protected] 1Famously, Boyle and Locke themselves denied that colors were primary qualities, and instead took them to be secondary qualities — dispositions to produce certain sorts of experiences in perceivers. Primary quality theories of color have been defended (sometimes under other names, such as ‘color physicalism’ or ‘color objectivism’) by many, including [Armstrong, 1968], [Hilbert, 1987], and [Byrne and Hilbert, 1997a]. 2I believe the argument is original to C. L. Hardin, although it has appeared (in different versions) in several places, including [Hardin, 1984], ([Hardin, 1988], xxi–xxii, 66–67), [Velleman, 1995], ([Thompson, 1995], 128–130, 135–139), and ([Maund, 1995], 42, 141, et passim). [Johnston, 1992] gives a related, but more complicated (and more epistemic) version of the argument that I shall not discuss here.