264 Progress of Theoretical Physics Supplement No. 173, 2008 Getting the Measure of Consciousness

The hard problem of consciousness is to explain the experience of qualia. But everything gets easier once we realise that what has to be explained is not how qualia can exist as objective entities but rather why the conscious subject should believe that they exist. This essay lays out a programme for doing this. It makes radical proposals as to how the “qualia illusion ” is created, and why sustaining this illusion is biologically adaptive. No one doubts that our experience of phenomenal consciousness — the felt redness of fire, the felt sweetness of a peach, the felt pain of a bee sting — arises from the activity of our brains. Yet the problem of explaining how this can be so has seemed to many theorists to be staggeringly hard. How can the wine of consciousness — the weird, ineffable, immaterial qualia that give such richness to subjective experience — conceivably arise from the water of the brain? As Colin McGinn has put it, it is like trying to explain how you can get “numbers from biscuits, or ethics from rhubarb”.1) Jerry Fodor has recently claimed “The revisions of our concepts and theories that imagining a solution will eventually require are likely to be very deep and very unsettling. There is hardly anything that we ma