You arrive at a fork in the road where one path leads to safety and the other to danger. Two twin guards stand at the fork: one always tells the truth, and the other always lies. What single question can you ask either guard to reliably identify the safe path?
Which path would the other guard tell me is safe?
Asking either guard what the other would say causes both to point to the dangerous path (the truth-teller accurately reports the liar's lie; the liar lies about the truth-teller's true answer). You then take the opposite path.
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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