Conceptualism and the problem of illusory experience

According to the conceptualist view in the philosophy of perception, we possess concepts for all the objects, properties, and relations which feature in our experiences. Richard Heck has recently argued that the phenomenon of illusory experience provides us with conclusive reasons to reject this view. In this paper, I examine Heck’s argument, I explain why I think that Bill Brewer’s conceptualist response to it is ineffective, and I then outline an alternative conceptualist response which I myself endorse. My argument turns on the fact that both Heck, in constructing his objection to conceptualism, and Brewer, in responding to it, miss a crucial distinction between perceptual demonstrative concepts of objects, on the one hand, and perceptual demonstrative concepts of properties, on the other.