Hayek’s discussion of the mind–body problem speaks directly to a topic that has dominated philosophy of mind for the past 35 years – qualia (quale for singular), a term of art that denotes this subjective ‘‘felt’’ quality to consciousness – the ‘‘unexplained residue’’ (Hayek, 1952/1976, 1.19, 8.85) that physicalism has failed to explain. Indeed, it has been said that, ‘‘[t]he problem of consciousness is identical with the problem of qualia” (Searle, 1998, p. 28). Qualia-talk went into overdrive in response to an argument presented by Frank Jackson (1982). Jackson’s argument, known as the ‘‘knowledge argument,’’ was conveyed through a thought experiment that I’ve entitled ‘‘Monochrome Mary.’’ ‘‘Monochrome Mary’’ poses the following question. What, if anything, would be experientially different for Mary on her release into a full color world given that she’d heretofore lived her whole life in a black and white world? Could she anticipate the experience even though she was in possession of a complete physical description of reality? Jackson concludes that Mary would still experience something new, in case of the thought experiment, the color red. One line of thought that challenges Jackson’s argument involves an equivocation of ‘‘know.’’ Is Mary’s new-found knowledge propositional or know-how/ability-type knowledge? For Hayek, qualia are know-how (Hayek, 1952/1976, 2.7). The Mary puzzle is intended to make for the view that qualia cannot be reduced to the level of physics and hence there cannot be a unified theory of consciousness. Dennett (1991) terms these thought experiments as an ‘‘intuition pumps,’’ a pejorative swipe at the a priorism he sees generated by them. Jackson, it should be noted, has since retracted his original conclusion; he is now of the view that the sensory side of psychology is, in principle, deducible from the world’s physical nature. Jackson’s thought experiment bears a striking resemblance to Hayek’s discussion in The Sensory Order, 1.95. Hayek took inspiration from C. D. Broad, the idea that an omnipotent being would still not be able to predict the qualia associated with a substance, for example, ammonia (Broad, 1925, p. 71). Here Hayek poses the question: how could one communicate the idea of vision generally and color in particular to the congenitally blind? In The Sensory Order, 1.97 and 1.98, Hayek cites physicist Kenneth Mees’ thought experiment as illustrating the distinction between the physical and the phenomenal orders. Mees asks us to consider the case of a congenially and totally deaf person confronted by someone playing a violin. Moreover, he asks us to suppose that this person knows nothing of sound even in a theoretical way. Confronted by the actions of the violin player, to the deaf person the actions will appear irrational. But, says Mees, if our deaf person was a scientist, he or she would eventually figure out that the movements of the violin bow generated vibrations that could be detected by equipment (the science of acoustics). Now whatever the issues Hayek has with Mees’ example, his conclusion is this: ‘‘the congenitally blind or deaf can never learn all that which the seeing or hearing person owes to the direct experience of the sensory qualities in question, because no description can exhaust all the distinctions which are experienced’’ (Hayek, 1952/1976, 1.102). The similarity of the conclusion shared by Hayek and Jackson is uncanny.