Does your conscious mind have any effect on your brain? Maybe not. Some claim that our consciousness is like the rainbow over a waterfall. The waterfall causes it, but the rainbow in turn has no effect on the waterfall. This point of view is called epiphenomenalism. It seems wildly counterintuitive and impossible to disprove.

Music: Beethoven, String Quartet No. 15 in A minor, Third Movement, Orion Quartet  Licensed through Creative Commons.

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