What RoboDennett Still Doesn't Know

Mary, the colour-deprived neuroscientist, embodies perhaps the best known form of the knowledge argument against physicalism (Jackson, 1982; 1986). She is a better- than-world-class neuroscientist. Living in an entirely black-and- white environment, she has learnt all the physical facts about human colour vision. She is supposed to be enough like us to be capable of having the sort of experiences that we would have on exposure to colour, but to be clever enough to know and understand the physical facts about her own colour vision, and to be able to work out all the relevant consequences of the facts which she knows. The key premise of this form of the knowledge argument is that when Mary is finally released from her black and white captivity and shown coloured objects, she will learn something: namely, what it is actually like to see in colour. Indeed, in Frank Jackson's original paper, he takes it to be 'just obvious' that Mary will 'learn something about the world and our visual experience of it' (Jackson, 1982, p. 130) on her release.