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So there is a city where every one either lies all the time or tells the truth all the time. They are denoted by either green hats for truth or red hats for lies. A guy is traving through, but is not a "Hat" of any color, but everyone else is. He comes to a river bank that he cannot cross without help. There are 3 "Hat's" on the other side, all offering to help him across. But here's the catch, he cannot differentiate colors. he asks them thier hat colors, the first guy is inaudible over the river. the second guy says "Im a green hat and the first says he is too and he is."and . the third guy says "no they are liars Im the green hat" How does he know who to trust?

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So there is a city where every one either lies all the time or tells the truth all the time. They are denoted by either green hats for truth or red hats for lies. A guy is traving through, but is not a "Hat" of any color, but everyone else is. He comes to a river bank that he cannot cross without help. There are 3 "Hat's" on the other side, all offering to help him across. But here's the catch, he cannot differentiate colors. he asks them thier hat colors, the first guy is inaudible over the river. the second guy says "Im a green hat and the first says he is too and he is."and . the third guy says "no they are liars Im the green hat" How does he know who to trust?

Little confused with that statement. Are you saying that the second guy is saying the first guy has a green hat? And that he does? Well if he does and the second guy said so, then he has a green hat, and the third guy has a red one. So trust the second guy. Even tho the first guy has a green hat, you can't hear him anyway.

In all reality tho, just because someone lies, does'nt mean they can't help you cross a river. :thumbsup:

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Listen to the second guy. Whether or not the first guy lies or tells the truth he's going to say that he has a green hat. By saying that the other guy said he has a green hat he has established that he (the second guy) tells the truth.

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B says "Im a green hat and the first says he is too and he is."

If truth: A and B are Green Hats, and will help.

If false:

if A said that he is a Green Cap and actually is, then B should say " he says he isn't and he isn't"

if A said that he is a Green Cap and he isn't then B should say "he says he isn't but he is"

so B has to be telling the truth.

C has to be a liar.

Trust A or B :)

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Little confused with that statement. Are you saying that the second guy is saying the first guy has a green hat? And that he does?

nevermind, when I first read it, it sounded like you (the author) was confirming that the first guy had a green hat. I see now after reading it again.

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Ok, trust the second guy, and heres why...The second guy said that the first guy said, I too have a green hat, right?

If the second guy was lying, that means the first guy would have said, I have a red hat, which is impossible for any of them to say. So the second guy has to be telling the truth. :thumbsup:

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So there is a city where every one either lies all the time or tells the truth all the time. They are denoted by either green hats for truth or red hats for lies. A guy is traving through, but is not a "Hat" of any color, but everyone else is. He comes to a river bank that he cannot cross without help. There are 3 "Hat's" on the other side, all offering to help him across. But here's the catch, he cannot differentiate colors. he asks them thier hat colors, the first guy is inaudible over the river. the second guy says "Im a green hat and the first says he is too and he is."and . the third guy says "no they are liars Im the green hat" How does he know who to trust?

it is possible that the second guy is lying the whole time as well and the third guy could be telling the truth. i would say that to know who to trust would to put them to the test. i would ask each one to put a rock in their hats and throw it across the river so that he could possibly see them. if one is a liar he will say ok but not do it, if one is telling the truth he will say ok and do it. :D

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If the first guy said "I'm wearing a green hat," and he was lying, then he must be wearing a red hat which is what you wear when you're a liar, right? So the second guy could be lying when he says "I'm wearing a green hat and so is the first guy." They're both lying and both wearing red hats. So the third guy would be telling the truth and would be wearing a green hat. He's the one you'd trust.

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Listen to the second guy. Whether or not the first guy lies or tells the truth he's going to say that he has a green hat. By saying that the other guy said he has a green hat he has established that he (the second guy) tells the truth.

Wouldn't it also establish that the first is a truth teller because the second guy said that he said he is a green hat and he is? If the second guy is telling the truth(which by your statement he is) and he says the first guy is a green hat, then he must be. Therefore, the third guy is a liar, because he said the first 2 are liars(which we have proven to be green hats).

In other words, the third can't be trusted, so belive the first two(or listen to the third and do the exact opposite from what he says).

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both the first and the second guy.

The second guy says that the first guy says that he is a green hat and the second guy vouches for him. So, in order for the second guy to be a liar, he would have to say the alternate color the first guy said. Whether the first guy was a lair or a truth teller he would say his hat is green no matter what. Therefore, the second guy would have to say that the first guy is a red hat because he has to lie about what the first guy said.

My head hurts.

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Put yourself in the shoes of the guy listening across the river. What is one phrase none of them could ever say?....My hat is red....If you always tell the truth you could never make such a statement(you'd be lying)...If you always lie you could never make that statement either(you'd be telling the truth) So if he hears the second guy say that the first guy said he has a green hat, then you have to know the second guy is telling the truth, because if he was lying, that would mean the first guy said he was wearing a red hat, which is a statement none of them could ever say. ;)

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What they said

A "I'm a green hat." (Not heard but this must be what was said.)

B "I'm a green hat AND A said he is a green hat AND A is a green hat"

C "A and B are red hats AND I am a green hat."

B is lying if any or all of the following is true:

-A is wearing a red hat

-A said he is wearing a red hat (not possible)

-B is wearing a red hat

I don't see a direct solution. Either

A and B are greens and C is red, or

A and B are reds and C is green.

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i wouldn't trust any of them and find a way across the river myself because

scenario A:

man 1 said he is wearing a green hat (definite)

man 2 says he is wearing a green hat (definite) he says that man 1 says he is wearing a green hat (definite) and he says that man 1 is really wearing a green hat (unsure)

man 3 says that he is wearing a green hat (definite) the others are liars (unsure)

so man 1,2,and3 are all unbelievable.

when i say definite i mean that what i said he said is all he could have possibly said without contradicting what he is.

you could believe man one but there is no proof he is telling the truth. :)

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bonanova Grand Master

bonanova

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So there is a city where every one either lies all the time or tells the truth all the time. They are denoted by either green hats for truth or red hats for lies. A guy is traving through, but is not a "Hat" of any color, but everyone else is. He comes to a river bank that he cannot cross without help. There are 3 "Hat's" on the other side, all offering to help him across. But here's the catch, he cannot differentiate colors. he asks them thier hat colors, the first guy is inaudible over the river. the second guy says "Im a green hat and the first says he is too and he is."and . the third guy says "no they are liars Im the green hat" How does he know who to trust?
Everyone must say their hat is green. So...

#1 said he's green.

#2 verified that, and said #1 was green. So they both can be trusted.

#3 disagreed, so he can't be trusted.

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