Explaining how you see a mental picture just invites a tinier viewer to look at it

If perception works by forming an inner 'picture' that the mind then inspects, something still has to do the inspecting — a little viewer inside the viewer. That viewer would need its own eyes and its own inner picture, triggering an infinite regress. The homunculus argument says any theory of mind built this way never actually explains perception, it just relocates the mystery.

— Daniel Dennett, Consciousness Explained — Dennett's critique of the 'Cartesian Theater', 1991
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