Problem:
On Predictable Island, everyone is either a liar (who always lies) or a truth-teller (who always tells the truth). You encounter Aerith who says, "Bob and I are both liars." What are they actually?
Solution
Solution:
If Aerith was a truth-teller, she would be lying, because it wouldn't be the case that they're both liars. Thus, she must be a liar. Therefore, the statement must be false, which means Bob has to be a truth-teller.
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