Abstract

At first pass, colour constancy occurs when one sees a thing in one’s environment to have a stable colour despite differences in the way it is illuminated. The phenomenon is intuitively grounded for example in everyday experiences in which something is partly shadowed but, in some sense, looks to be uniformly coloured. After a brief introduction to the colour constancy concept (§0) and the science of colour constancy (§1), my focus is on the significance of colour constancy for two intertwined philosophical issues. The first is colour ontology, where constancy has been used to argue for the objectivity of colour, and in particular for a reductive form of it (see §2). The second is colour constancy’s complicated connection to colour experience and colour epistemology. Colour constancy is a subtle phenomenon: it is situated at the intersection of perceptual experience and judgement; it is influenced by myriad forces within our visual-cognitive systems; and is likely a composite of interestingly disparate phenomena. I approach this suite of issues from the perspective of the given in colour perception (§3). As will become plain, the ontological and epistemic issues are related in important ways. This does not, however, detract from the value of focusing on each individually.