Anti-luminosity

Timothy Williamson (2000) reckons that hardly any mental state is luminous, i.e. is such that if one were in it, then one would invariably be in a position to know that one was. This paper examines an argument he presents against the luminosity of feeling cold, which he claims generalizes to other phenomenal states, such as e.g. being in pain. As we shall see, the argument fails. However, our deliberations do yield two anti-luminosity results: a simple refutation of the claim that one invariably knows whether one feels cold or not,1 and a counterexample to the luminosity of knowing—in effect, a counterexample to the (KK)- principle.