A remote island has a unique social structure. Individuals are either 'Truth-tellers' (who always speak the truth) or 'Tricksters' (who always lie). You encounter three inhabitants: X, Y, and Z.
X says: "Y is a Trickster."
Y says: "Exactly one of us is a Truth-teller."
What can you definitively conclude about Z?
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Let me quickly re-check the logic:
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Let T = Truth-teller, L = Trickster (liar).
X says: “Y is a Trickster.”
Y says: “Exactly one of us (X, Y, Z) is a Truth-teller.”
Case 1: Assume X is T.
Then Y must be L.
Y’s statement must be false: “Exactly one of us is a Truth-teller” is false.
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Truth-tellers so far: X (1).
If Z were L, then exactly one (X) would be T → Y’s statement would be true, contradiction.
So Z must be T.
Configuration: (X T, Y L, Z T) works.
Case 2: Assume X is L.
Then “Y is a Trickster” is false → Y is T.
Now Y’s statement must be true: exactly one of X, Y, Z is T.
Both configurations are consistent:
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In one, Z is T.
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In the other, Z is L.
So Z can be either a Truth-teller or a Trickster