Steven Pinker’s introductory psychology lectures split consciousness the way the philosopher David Chalmers did, into easy problems and a hard problem.
The easy problem is access. Some information is available to us: the objects we see, our plans, the content of a sentence. Some is not: the rules of syntax, the image on the retina, the commands to our muscles.
“Easy” is an in-joke. It is still very hard, but science has a way in. Attention decides what gets through. The leading account is a global workspace, a blackboard where a small, relevant subset of information is posted for memory, language, and planning to share.
The hard problem is sentience: why any of this feels like something. Philosophers call the raw feels qualia, such as the painfulness of pain or the smell of cinnamon. Is your blue my blue? Could a program feel? Could there be a zombie that acts like us with nobody home?
The lectures list the answers on offer. Dualism leaves too many open questions. Information-processing theories cannot say why a flow of bits should feel like anything, and they slide toward panpsychism, with conscious thermostats. Neural theories point to brain rhythms, and Penrose points to quantum gravity, and both still owe us the how. The mysterians say our brains may lack the means to solve it. And Daniel Dennett says there is no hard problem: sentience, as something over and above the machinery, is an illusion.
I side with Dennett. I expect consciousness to get a materialist explanation in the end. Life itself looked like this kind of mystery in the nineteenth century, and it turned out to be molecules, organized by natural selection. Descartes’s objection, that I cannot be wrong about my own experience, does not move me.
That does not make the mysterians wrong about today. Chomsky’s limits on human understanding are real, I think, for the brain as it now is. They hold until we find a way to augment it, which may or may never happen.