A particular, unusual island is populated entirely by truth-tellers and liars, all outwardly identical.
The truth-tellers, bound by their blind adherence to their strict moral code, exclusively tell the truth. Their unflinching honesty is one of their many shortcomings. When asked for the truth, they unquestionably provide the truth, and it's always the whole truth. Often more truth than necessary. The idea of the secret is foreign to them. Their brutal honesty fails them in their personal relationships, causing them to come across as gruff and matter-of-fact with their unwanted criticisms of others when in fact they mean well. They are often taken advantage of. Their credit card numbers are taken. Everybody knows where their spare house key is hidden.
The liars have it no easier. Being put off by the lives they perceive the truth-tellers to live, the liars have reached the flawed conclusion that all truth is problematic, and as such have taken a hard-line stance against it and always exclusively tell lies. This behavior also stems from their general insecurities - they worry that their particular truths about themselves wouldn't represent them well, and would rather paint a rosier picture of things with a simple fib or a slight exaggeration. Communication with the liars on the island is difficult and tiresome. They are unable to hold steady employment.
Life is hard here.
All of the truth-tellers and liars on the island have been gathered into three enormous boxes. One box contains only truth-tellers, one contains only liars, and one contains a mix of both. The three boxes are labeled TRUTH-TELLERS, LIARS, and MIX, but each box has an incorrect label applied to it.
You have been hired for a small fee to fix the labels on the boxes. Your employer has asked you not to concern yourself with the purpose of these boxes. It is not your job to worry about the ethics of this situation - there are higher-ups who do that. Your job is to fix the labels.
You do have some misgivings about the whole thing, but you need the money, so you figure that now isn't the time to cause waves. Maybe if you get invited to relabel boxes again in the future you'll ask a few more questions. For today, you're just going to see how this shakes out.
You can extract a person from a box whenever you like to ask them what they would say if you asked them if they were a truth-teller or a liar. What is the fewest number of people you need to query in order to correctly label the boxes?
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