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One of those "always tells the truth/always lies" riddles, with a twist
I heard a new twist on the old "one man always tells the truth, one man always lies" riddles that appealed to the computer nerd in me and may similarly appeal to your own personal inner nerd. If you don't have a personal inner nerd I cannot guarantee that you'll enjoy what follows.
Imagine a land, a vast and confusing land that inhabits three different types of people: Knights, Knaves and Knexuses. Knights, being the honorable type will always tell the truth. Knaves, being young and jerky will always lie. A Knexus is a peculiar sort in that he will answer any question either "Yes" or "No", his response being the XOR of how the Knight and Knave would answer the same question. That is, when a Knight and a Knave would both have the same answer for a question posed to the Knexus, he will say "No". If the Knight and the Knave would have different answers to the question posed to the Knexus, he will say "Yes". For example, consider the question: "Are you a knight?" Both a knight and a knave would answer in the affirmative, so a Knexus would answer No. On the other hand, a Knight's answer and a Knave's answer to the question, "Does two plus two equal four?" would be different, so a Knexus would answer Yes. Got it? Let's proceed.
To complicate matters, these people in this dumb land have their own language. You don't speak this language, but you know that they have their distinct words for "Yes" and "No".
You may ask three questions, each question directed at either the Knight, the Knave or the Knexus. Only the person that you ask will respond. You may ask the same person multiple questions and you may repeat a question (up to 3 times if you like). Find out who is who.
IMPORTANT: I only just heard about this riddle and haven't been able to work on it yet. I plan to do that later today. So if you see me in #predicate PLEASE don't give me your answers, as that will ruin my fun. You should feel free, however, to ask me questions about the riddle and how it works. Thank you for your continued support.
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Question:
Do the Knight, Knave, and Knexus all know the identities of the other two people? I.e. can the Knight identify which is the Knave and which is the Knexus, or do they only know that they are a Knight?
Wait, if I ask a question of
Wait, if I ask a question of the Knight, asking him if he is a Knight, won't he just say "yes" and then it's one down and two to go? And then I could direct a question to the Knave and ask him if he is the Knave, and he'll say "no" and then we've got it? I may have read the question wrong but the way you set it up is that you may direct a question to any one of the three.
It's unclear, but probably not *that* easy...
I'm guessing that since the point of the riddle is to determine who is whom (although, y'know, it doesn't actually say that anywhere, come to think of it), it's probably assumed that you don't know beforehand which is which.
The point of that sentence, I think, is to make it clear that you can only ask one person one question at a time, rather than having all three answer at once. You can direct your question(s) to X, Y, or Z, but you don't know the identity of the person you're asking. So you can't just "ask the Knight something," you have to determine through your questions both a) which is which, and b) yes from no.
1) Yes. Each individual
1) Yes. Each individual knows everything about the other two.
2) If you ask someone if he's the Knight and he says 'Yes', you know that he is either the Knight or the Knave, because the Knight will always tell the truth and the Knave will always lie. Note that in this case, if you asked the Knexus if he was a Knight, he would say 'no', because the Knight and the Knave would both answer the same way- saying "Yes"
3) It totally says "Find out who is who". Everything else is correct.
I can get the word for No in one question.
Which gives you yes by process of elimination.
The question is "Are you a Knave? (or, IS either of the other 2 a Knight?)". The Knight answering truthfully must say No, the Knave, lying, must say No, and the Knexus gives the XOR of No and No, which is No. After that, I ain't making much progress.