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Puzzles/Logic puzzles/Knights, Knaves & Spies II
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Puzzles | Logic puzzles | Knights, Knaves & Spies II
We have three people one of whom is a knight, one a knave, and one a spy.
The knight always tells the truth, the knave always lies, and the spy can
either lie or tell the truth. The three persons are brought before a
judge who wants to identify the spy.
A says: "I am not a spy."
B says: "I am a spy."
Now C is in fact the spy. The judge asks him: "Is B really a spy?"
Can C give an answer so that he doesn't convict himself as a spy?
Solution