A critique of Cohen's relational theory of color
Jonathan Cohen's relational theory of color defines color as a relation between an object, a subject and the viewing conditions. His theory overcomes color-physicalism's anthropocentric conclusion that only some human visual systems have veridical color vision. According to relationalism, (almost) all perception is veridical. But relationalism faces two intractable problems. First, our visual experience presents a tomato as being intrinsically red rather than "red for me in these conditions." Unless relationalism can explain how our phenomenology of sensuous color experience fits into the causal structure of the world, it cannot fit color into the causal process, though at the least color must cause our sensuous experience of color. Secondly, in defining the relationship between an object's being red and looking red to an observer, relationalism specifies only that "If x looks green to S in C, x is green for S in C." Relationalism must therefore provide an independent account of what it is for an object to look green. Without an independent account it fails to pick out the specific mental events meant by "looks green." Because there are no illusions in relationalism, it's also true that "If x is green for S in, then x looks green to S in C." But this produces a regress problem. In light of these two problems, relationalism cannot be the correct account of color.