We sometimes forget how far we are from solving the mystery of consciousness. An anecdote from 1994 might help us understand. Picture an utterly boring, pointless conference in Tucson, Arizona, one of whose attendees was an obscure philosopher from Australia, scheduled to give the third talk. And shook everything up: The brain, Chalmers began by pointing out, poses all sorts of problems to keep scientists busy. How do we learn, store memories, or perceive things? How do you know to jerk your hand away from scalding water, or hear your name spoken across the room at a noisy party? But these were all “easy problems”, in the scheme of things: given enough time and money, experts would figure them out.…