Barbara Gail Montero

Mary knows all there is to know about physics, chemistry and neurophysiology, yet has never experienced colour. Most philosophers think that if Mary learns something genuinely new upon seeing colour for the first time, then physicalism is false. I argue, however, that physicalism is consistent with Mary's acquisition of new information. Indeed, even if she has perfect powers of deduction, and higher-level physical facts are a priori deducible from lower-level ones, Mary may still lack concepts which are required in order to deduce from the lower-level physical facts what it is like to see red