Three islanders—A, B, and C—are each either a Knight (who always tells the truth) or a Knave (who always lies). A says: 'B is a Knave.' B says: 'C is a Knight.' C says: 'There are no Knights among us.' What type of islander is B?
Knave.
If C were a Knight, C's claim that there are no Knights would be a lie, which is impossible. Thus C is a Knave. Since C is a Knave, B's statement that C is a Knight is false, making B a Knave as well. Finally, A's claim that B is a Knave is true, making A a Knight.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Hard. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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