Four alchemists each bring a single potion to a council: two healing potions, one sleeping potion, and one poison. Alchemist A says, 'My potion is not poison.' Alchemist B says, 'Alchemist C brought a healing potion.' Alchemist C says, 'Alchemist D brought the poison.' Alchemist D says, 'Alchemist A is lying.' If exactly one alchemist is lying, who brought the poison?
Alchemist D
Statements A and D directly contradict each other, meaning one of them must be the liar and all other statements must be true. Since C's statement must be true, C correctly identifies that Alchemist D brought the poison.
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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