27 replies to this topic

[rookie1ja]

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.

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Spoiler for Solution

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.

[thinkoutabox]

If A is a liar(which is the case here) then either first statement could be false or second statement could be false or both could be false. So your conclusion then A is lying monkey assumes that both statements are false and neglects the possibility of first statement being false and second being true. If later is the case, then A is a lying human.

[thinkoutabox]

hey
sorry..i missed the part of hypothesis that they only tell all truths or all lies. Then the conclusion you've got is correct. Nice puzzle!

[colorclown26]

Took a while. Good puzzle!

[spazchik]

I just wanna say that monkeys can't talk... so how can they lie? And surely you can tell from seeing them that the human was human and not monkey (unless being contacted via radio or something).
Sorry if I got some facts wrong, I just like being technical.

[Slick_Rick9009]

First off, to account for not being able to know what species they are by simply looking at them you might be blind, they could be wearing costumes, you might be on the opposite sides of a wall, you could communicate via radio, as you suggested, or any number of other possibilities. But, anyway, I actually got this one in like 5 seconds (litterally) since I read almost all of the of the other puzzles here so I already knew basically what was gonna happen. It was a great puzzle though, keep 'em comin!

[jaygupta]

really good one

[LadyDanser]

Definitely a good one. It took me a second to realize they could both be lying.

[hellsingiscool]

So wait, if you take out the monkey and human part it will look like this
A: B is a liar. I am telling the truth.
B: A is telling the truth.

And that means that it is a paradox because B is saying that A is telling the truth but if A is telling the truth, B is lying so that means A is lying and B is telling the truth and it's right back where it started right?

[aishi_khurana]

Island Baal - Back to the Logic Problems
There are people and strange monkeys on this island, and you can not tell who is who. 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.

IF B IS A LYING MONKEY THEN HE WOULD NOT SAY A IS TRUTHFUL....WHICH MEANS HE'S AGREEING THAT HE'S A LYING MONKEY.....CONTRADICTION!!!!!NOW IF A IS LYING THEN B IS A HUMAN AND HE HIMSELF IS A MONKEY...THIS IS AGAIN CONTRADICTION!!!!!