perplexus.info :: Paradoxes : The Exclusive Club

The Exclusive Club (Posted on 2013-07-01)

There is a club called the Exclusive Club. Somebody is a member of this club if and only if he has not shaved anybody who has shaved him. In other words, X is a member of the Exclusive Club if and only if there is no Y such that X shaves Y and Y shaves X.

A barber once claimed that he had shaved every member of the Exclusive Club and nobody else. Show that the barber's claim cannot be true.

No Solution Yet Submitted by Math Man

Rating: 5.0000 (1 votes)

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re: solution

| Comment 2 of 8 |

(In reply to solution by Daniel)

3)..... A non club member: then the barber meets the requirements for membership and thus must be a member, contradicting his not being a member....

This is a very weak argument:

If I meet the requirements for membership in Rotary that does not imply that I am a member.

Posted by Ady TZIDON on 2013-07-01 18:39:56

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