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A comment on Why Do Mirrors Flip Things Horizontally but Not Vertically? Here's the Physics. Parent comment

Re:Why Do Mirrors Flip Things Horizontally but Not Verticall... by sumtechguy on Wednesday October 07, 2020 @01:24PM (#24710515)
Or there is a second barber and they shave each other? If there is only one barber then it is a paradox.
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Re:Why Do Mirrors Flip Things Horizontally but Not Verticall... by bigbubba on Wednesday October 07, 2020 @01:30PM (#24710569)
There is only one barber and he's not bald or otherwise excluded from the 'everybody' in "he shaves everybody who doesn't shave themselves." It's not a lateral thinking problem, or a matter of thinking outside the box. The scenario described is simply impossible. Everybody, including the barber, is either shaved by the barber or [XOR] shaves themselves, which is impossible in the case of the barber.

See also: https://en.wikipedia.org/wiki/Russell%27s_paradox

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