# Two doors, but only ONE person [liar / truth teller]

#1
I'm sure everyone knows this problem and what the solution is. Very briefly, you approach two doors, one leads to death and the other to freedom. You want freedom. There are two men standing outside the door, one of which always lies the other always tells the truth. You don't know which is which. What is the question you have to ask to gain freedom and avoid death? Because you all know it I won't post it, and for those who don't, you can try and figure it out

However the other day, I was trying to come up with a solution for the same scenario, but instead of two people being there, there was only one, and you didn't know his identity. I.e you didn't know if the person ALWAYS told the truth, or if the person ALWAYS told a lie. Once again, you can ask him only one question to correctly identify the life giving door.

This is the rendition as I understand it:

1) You approach two doors, one of which leads to death and the other leads to freedom
2) There is a man waiting at the doors and you may ask him one question only
3) This man either always tells the truth or always tells a lie
4) The man knows the identity of the two doors
4) You don't want to die and you want freedom.

What is the question you ask the man? I think I figured out the solution [slightly dodgy], but what do you think the question is? [If you think it is impossible please put forward an argument as to why you think this is the case].

I've done a google search and I haven't found any sources which ask this particular question. However if this is already an established question, many apologies, or you've figured out the answer, please spoilerise
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12 years ago
#2
So basically, I have no idea
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#3
(Original post by *Hannah)
Think I've heard this one before, though I may be wrong
Spoiler:
Show
Don't you ask which door the other one would tell you to go through and then go through the other one - if that makes any sense?
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12 years ago
#4
Spoiler:
Show
I ask him if he wants to come with me. If he says yes, it's the door to freedom.

Wait, he might lie. Oh dang.
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12 years ago
#5
You ask one man which door the other would tell you to go through for freedom, and then pick the other door, right? Because then if the man you ask is the liar, then his answer will be a lie therefore the other door is the one to go through, and if the man you ask is the one who tells the truth, he'll tell you what the lie would be, and therefore you should go through the other door.

Edit: Oops, so didn't read that properly
No idea then!
0
#6
(Original post by Cultivated)
Spoiler:
Show
I ask him if he wants to come with me. If he says yes, it's the door to freedom.

Wait, he might lie. Oh dang.
Maybe he'd say no regardless
0
12 years ago
#7
don't you ask which the other one would do?
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#8
0
12 years ago
#9
No

You ask, if I were to ask the other one which door he was guarding what would he tell me?

The one who lies will lie about what the other says and tell you what door he is actually guarding

The one who tells the truth will tell you what the other guys lie would be

Traditionally the two guards are guarding heaven and hell in the conundrum
0
12 years ago
#10
(Original post by n1r4v)
Haha, I realised that...I should really pay more attention to what I'm reading
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12 years ago
#11
Maybe:
Spoiler:
Show
If you always lie then which door should I go in, if you always tell the truth which door should I go in?
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12 years ago
#12
yeah you ask what the other bloke would say is the one for freedom, and they'll both point to the death one, so you go into the other one and liiiiiive

EDIT:
OH SORRY I DID NOT READ THE OP

I don't know
0
#13
(Original post by a_t)
No

You ask, if I were to ask the other one which door he was guarding what would he tell me?

The one who lies will lie about what the other says and tell you what door he is actually guarding

The one who tells the truth will tell you what the other guys lie would be
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12 years ago
#14

???

I'm trying to remember from the film Labyrinth lol
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#15
(Original post by a_t)
Oh, its impossible then
Hmm I thought that at first... but I've got a solution [admittedly a bit dodgy]... give a reason as to why you think this though.
0
12 years ago
#16
It's an easy riddle, similar to this one-

On your travels across India, you come to a road which has a fork in it. One path leads to the village of truth, where all inhabitants constantly speak the truth and act honestly, the other path leads to the village of liars, where all inhabitants constantly tell lies and act dishonestly.

A man is standing at the fork of the road. You do not know whether he comes from the village of truth or the village of liars. What question do you ask him to ensure you end up in the village of truth?
0
12 years ago
#17
Haha, is nobody capable of reading the op?!

I have no idea, I've always sucked at things like that.
0
12 years ago
#18
(Original post by Chrosson)
That would be somit like 'What village are you from?' wouldnt it?
Kinda similar to my previous answer.
That wouldn't tell you which path to take though.
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12 years ago
#19
I would take out my mobile phone, and say, "Is this a mobile Phone?" If he says yes, its the truth guy, if he says no, its the liar.
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12 years ago
#20
(Original post by ieo91)
I would take out my mobile phone, and say, "Is this a mobile Phone?" If he says yes, its the truth guy, if he says no, its the liar.
Well done. But you will still not know which door is which.
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