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A calls B a knave, B says A and C are alike

knights-and-knaveslogiccase-analysis

Three islanders, A, B and C, each a knight or a knave.

  • A says: "B is a knave."
  • B says: "A and C are of the same type."
  • C says nothing.

What is C? You may find that A and B cannot be individually identified; the puzzle only asks you to be certain about C.

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You will not be able to determine A and B individually. Split into the two cases for A and see what each forces for C.

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The theory behind this question.

Cheryl's Birthday and Iterated KnowledgeLogic and QuantifiersOne Question, Two Guards, One DoorProof Techniques: Direct, Contrapositive, ContradictionAdaptive Versus Pre-Committed Weighing Strategies

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