FINE-GRAINED COLOUR DISCRIMINATION WITHOUT FINE-GRAINED COLOUR

Rene Jagnow [2012] argues that David Rosenthal's theory of consciousness cannot account for certain experiences that involve colours so fine-grained that we do not and cannot have concepts of them. Jagnow claims that an appeal to comparative concepts such as BEING SLIGHTLY DARKER THAN cannot help Rosenthal, since, in order to apply such concepts, we would already need to be conscious of two distinct fine-grained colours. The present paper contests this claim. It appeals to the Cornsweet illusion and some other visual phenomena, in order to argue that our visual systems can and do represent brutely comparative matters.