On a remote island, inhabitants are either Knights (who always tell the truth) or Knaves (who always lie). You meet two inhabitants, X and Y. X says: 'At least one of us is a Knave.' What are X and Y?
X is a Knight and Y is a Knave
If X were a Knave, X's statement would be true, which contradicts a Knave's nature to lie. Thus, X must be a Knight telling the truth. Since X's statement is true and X is a Knight, Y must be the Knave to satisfy 'at least one of us is a Knave'.
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: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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