Book excerpt: The Red and the Real offers a new approach to longstanding philosophical puzzles about what colors are and how they fit into the natural world. Jonathan Cohen argues for a role-functionalist treatment of color - a view according to which colors are identical to certain functional roles involving perceptual effects on subjects. Cohen first argues (on broadly empirical grounds) for the more general relationalist view that colors are constituted in terms of relations between objects, perceivers, and viewing conditions. He responds to semantic, ontological, and phenomenological objections against this thesis, and argues that relationalism offers the best hope of respecting both empirical results and ordinary belief about color. He then defends the more specific role functionalist-account by contending that the latter is the most plausible form of color relationalism.