Facing Up to the Problem of Consciousness
David Chalmers · 1995
"Consciousness splits into 'easy problems' (explaining cognitive functions like attention or memory, tractable to standard science) and the 'hard problem' — explaining why any physical processing is accompanied by subjective experience at all — which resists reduction to physical explanation in principle, not just in current practice."
Before this paper, consciousness in cognitive science often meant something functional and explainable: how we discriminate stimuli, integrate information, report mental states. Chalmers's move was to isolate a residue that survives even a complete functional explanation: even if you explain every mechanism behind how a brain processes red light and reports 'I see red,' you haven't yet explained why there's something it is like to see red at all, rather than the processing happening with no subjective experience attached.
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The Ego Tunnel
"The self is not a thing you have but a transparent model your brain constructs and mistakes for direct reality — an 'ego tunnel' you can never fully see because you're always inside it."