Three gods, A, B, and C, are called, in no particular order, True, False, and Random. True always speaks the truth, False always lies, and Random answers randomly. You can ask three yes-no questions to any combination of gods. What is the minimum number of questions needed to identify all three?
Three questions
Because the Random god makes true/false identification unpredictable, figuring out who is who requires carefully structured questions to isolate the Truth and Falsehood speakers first, which takes at least three queries.
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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