  Whether facts about experience are indeed epistemically limited in this way is open to debate (Lycan 1996), but the claim that understanding consciousness requires special forms of knowing and access from the inside point of view is intuitively plausible and has a long history (Locke 1688). Thus any adequate answer to the What question must address the epistemic status of consciousness, both our abilities to understand it and their limits (Papineau 2002, Chalmers 2003). (See the entry on   self-knowledge.)