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Island Baal


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Island Baal - Back to the Logic Problems

There are people and strange monkeys on this island, and you can not tell who is who (Edit: untill you understand what they said - see below). They speak either only the truth or only lies.

Who are the following two guys?

A: B is a lying monkey. I am human.

B: A is telling the truth.

Island Baal - solution

Conjunction used by A is true only if both parts are true. Under the assumption that B is an honest man, then A would be honest too (B says so) and so B would be a liar as A said, which would be a conflict. So B is a liar. And knowing that, B actually said that A is a liar, too. First statement of A is thus a lie and B is not a lying monkey. However, B is lying which means he is not a monkey. B is a lying man. The second statement of A indicates that A is a monkey – so A is a lying monkey.

I believe the real issue with the puzzle is the word "and", which is missing from the conjuctive statement of person A. As written, person A is making two statements. By definition of the puzzle, those statements are either both false, or both true. There is no "AND" between them, so the solution of assuming one part can be true and the other part false does not apply. Add the word "AND", and then the solution is correct.

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  • 3 months later...

A: is a Lying Monkey

B: is a Lying Human

Hence when A says

"B is a lying monkey. I am human."

Both the statements are lies.

And when B says "A is telling the truth."

The statement is again a lie


A cannot be truthful because if he is , then B's statement would be a contradiction. If he is not truthful, his second statement would also be a lie. Hence he is not human either. Hence he is a lying monkey.

B cannot be truthful either as he says that A is truthful which A is not. He can only be a lying monkey or a lying human.

Since A's statement "B is a Lying monkey" is a lie... B can only be a lying human

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  • 3 weeks later...
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