What is consciousness?

Scientists and philosophers have suggested everything from quantum effects to information integration to brain-wave patterns. Some deny that consciousness exists at all; others argue that consciousness couldn't possibly be the result of just the brain. The scientific organizers of one of the principal consciousness conferences, in fact, deliberately let in woo-woo stuff about altered states and past lives on the principle that we have no idea where the answer might come from.

How Weird Is Consciousness?