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Barber Paradox (Russell's Paradox)
Posted 25 November 2007 - 07:23 PM
Posted 01 December 2007 - 12:42 AM
Posted 03 December 2007 - 06:52 AM
The paradox is pretty clear in that wording: if the set-of-all-sets-that-do-not-contain-themselves doesn't contain itself, it SHOULD contain itself and once it does contain itself, it can no longer contain itself.
So if the barber only shaves people who do not shave themselves, does he shave himself? No, but then he should, but if he does, he shouldn't, etc, around and around.
Posted 14 December 2007 - 08:55 PM
Posted 15 December 2007 - 03:10 AM
There was a barber in a village, who promised to shave everybody, who does not shave himself (or herself).
Can the barber shave himself and keep the mentioned promise?
Of course, he never said he wouldn't shave anyone who did shave himself.
Don't change the wording! It totally destroys my theory!
Edited (better wording?):
In a village, the barber shaves everyone who does not shave himself/herself, but no one else.
Who shaves the barber?
Posted 17 December 2007 - 08:24 PM
Posted 19 December 2007 - 01:04 AM
Posted 23 December 2007 - 11:40 PM
Per se, it is not a paradox, as it does not introduce a strict formal contradiction in the set of logical rules governing the reasoning, but is, as defined by Godel, 'unsolvable', i.e. it requires introducing a bending of existing rules or the introduction of a new one to be resolved (in the formal logic understanding of the term)
As such, such so-called 'paradoxes' are at the base of all modern mathematics and physics (from non-Euclidian gemoetries to the formulaes governing the mechanics of a television set)
Posted 01 January 2008 - 03:00 PM
Additionally, someone who doesn't shave - a child - could shave the barber.
Posted 30 January 2008 - 03:46 AM
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