Four travelers sit around a circular campfire. Arthur says, 'The person to my left is lying.' Beatrice says, 'Arthur is telling the truth.' Charles says, 'Beatrice is lying.' Diana says, 'Charles is telling the truth.' Exactly one of these travelers is telling the truth, and the other three are lying. Who is the truthful traveler?
Beatrice
Test each person. If Arthur is true, Beatrice must be true (violating the 'only one truth' rule). If Beatrice is true, Arthur's statement ('the person to my left is lying') must be a lie, which matches the setup since Beatrice is indeed telling the truth. If Charles or Diana were the sole truth-tellers, it creates contradictions with the neighbor relationships. Thus, Beatrice alone is telling the truth.
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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