Qualia, if there are such, are properties of sensations and perceptual states, namely the properties that give them their qualitative or phenomenal character – those that determine “what it is like” to have them. I combine the belief that there are qualia with adherence to a materialist and functionalist view of mind, and thus hold a “compatibilist” view that puts me in a crossfire between two sorts of “incompatibilists” – those who believe in qualia and think that this supports a rejection of functionalist or materialist views, and those who deny the existence of qualia, or “quine” them (as Daniel Dennett puts it), as part of their defense of functionalist or materialist views.

My compatibilist position (see Shoemaker 1975a, 1975b, 1981, and 1982) can most conveniently be sketched by reference to the “inverted qualia argument” and the “absent qualia argument”, both against functionalism, advanced some years ago by Ned Block and Jerry Fodor (1972). I agree with Block and Fodor that the inverted qualia argument shows that individual qualia are not functionally definable. This is my one concession to incompatibilism. But I maintain that there is a good sense in which the qualitative character of an experience can be accommodated in a functionalist account. A functionalist account can be given of what it is for a property to be a quale, of what it is for mental states to have qualitative character, and of what it is for mental states to be in greater or lesser degrees similar in qualitative character.