Frank Jackson’s famous Knowledge Argument moves from the premise that complete physical knowledge about experiences is not complete knowledge about experiences to the falsity of physicalism. Some physicalists have countered by arguing that what Jackson’s Mary, the perfect scientist who acquires all physical knowledge about experiencing red while being locked in a monochromatic room, lacks before experiencing red is merely a piece of recognitional knowledge of an identity, and that since lacking a piece of recognitional knowledge of an identity does not entail lacking any pieces of knowledge of worldly facts, physicalism is safe. I will argue that what Mary lacks in her room is not merely a piece of recognitional knowledge of an identity and...