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Topic: Heaven and Hell (Read 7168 times) |
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KjSlag
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Heaven and Hell
« on: May 28th, 2007, 7:05pm » |
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Because you like riddles, after you die God decides to give you a riddle to decide your fate. He puts you in a room in which there are two doors and two guards. One door leads to Heaven, and the other to Hell. One guard always tells the truth, the other always lies. God tells you that you may ask one guard one yes or no question. The guard will then answer the question (keep in mind that one of the guards will lie and you don't know which one will lie). Then you must walk though one of the doors. Your goal is obviously to walk though the door that leads to Heaven. What question will you ask in order to know for sure which door leads to Heaven?
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JiNbOtAk
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Re: Heaven and Hell
« Reply #1 on: May 28th, 2007, 10:19pm » |
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This look reaaaaly familiar..
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Icarus
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Re: Heaven and Hell
« Reply #3 on: Jun 3rd, 2007, 3:22pm » |
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Of course, in that thread, the puzzler made the mistake of tying the guards to particular doors, so it was sufficient to simply find out which told the truth and which told lies. This puzzle is harder for being better stated. Here, knowing which guard is telling the truth and which is lying is useless. It is the door that you need to identify.
(However, there are other threads where the problem was properly stated.)
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Bishamon
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Re: Heaven and Hell
« Reply #4 on: Jun 8th, 2007, 2:27am » |
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Ask the first guard if he is the guard.
If he answers "yes", that means the second guard is the Liar, we can then ask him if a particular door leads to heaven. We will get the opposite answer.
If he answers "no", that means that the first guard is the liar. we can then proceed to ask the second guard if a particular door leads to heaven and get the correct reply.
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towr
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Re: Heaven and Hell
« Reply #5 on: Jun 8th, 2007, 3:01am » |
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on Jun 8th, 2007, 2:27am, Bishamon wrote:Ask the first guard if he is the guard.
If he answers "yes", that means the second guard is the Liar, we can then ask him if a particular door leads to heaven. We will get the opposite answer.
If he answers "no", that means that the first guard is the liar. we can then proceed to ask the second guard if a particular door leads to heaven and get the correct reply.
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But you can only ask one question in total; not one question to each.
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Bishamon
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Re: Heaven and Hell
« Reply #6 on: Jun 8th, 2007, 6:08am » |
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My apologies. I did'nt see that the first time i read it 
Well, then just as in the other similar problems, the question to be posed will be "What will the other guard say if I were to ask him if this door lead to heaven?"
4 possible scenarios exist.
I). I was talking to the guard who always lies and was pointing to the right door. In which case he would say "No."
II). I was talking to the guard who always lies and was pointing to the wrong door. He would reply "Yes."
III). Truthful guard and right door. Answer - "No"
IV). Truthful guard and wrong door. Answer - "Yes"
As one can see, we do the opposite of wat we hear.
Hope, I did'nt miss anything out this time. 
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Sir Col
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Re: Heaven and Hell
« Reply #7 on: Jun 8th, 2007, 7:51am » |
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on Jun 8th, 2007, 6:08am, Bishamon wrote:| Hope, I did'nt miss anything out this time. |
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You ask, "What will the other guard say if I were to ask him if this door lead to heaven?"
The liar could say, "Neither of these doors lead to heaven." Which is a blatant lie.
As the truth teller is aware of the lengths a liar will go to in order to deceive and as a liar knows that the truth teller would provide an honest answer, either of them could reply, "How could I possibly know the mind of a liar?"
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Bishamon
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Re: Heaven and Hell
« Reply #8 on: Jun 10th, 2007, 4:01am » |
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What you said would be have been correct if I had asked something like "What will the other guard say if I were to ask him if which door leads to heaven?"
But since i am specifically pointing a particular door and asking him that question, I imagine he can only answer in the positive or the negative as said in the question. Anways, it has also been mentioned in specifically that we can only ask a "yes-no question".
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Grimbal
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Re: Heaven and Hell
« Reply #9 on: Jun 10th, 2007, 8:20am » |
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Assuming each guard guards one door, you can ask one guard:
Is the door to Hell guarded by a liar?
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Sir Col
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Re: Heaven and Hell
« Reply #10 on: Jun 10th, 2007, 2:51pm » |
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on Jun 10th, 2007, 4:01am, Bishamon wrote:| Anways, it has also been mentioned in specifically that we can only ask a "yes-no question". |
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It's all well and fine demanding that they can only answer yes/no to a question, but what would happen if you asked if the Riemann hypothesis is correct?
A truth teller is entitled to answer, "I don't know."
It is interesting to think about what a liar would say to the question about the Riemann hypothesis. Is it really dishonest to say, "Yes" when you don't know. What would happen if it turns out to be true?
Anyway, back to my point...
If the liar were asked the question they would know the response of the truth teller. So they would be lying by saying, "I don't know."
If the truth teller were asked the question they would be aware of the complex and unpredictable nature of the liar, so they could answer, "I don't know."
Or, as I pointed out, either of them could say, "How could I possibly know the mind of a liar?"
The difficulty with this type of problem is that they require the person to co-operate. If I were a compulsive liar then I would do my very best to be as deceptive as possible, which means masking my deception. That is, I would always try to answer questions in a way that would not disclose my dishonest nature.
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Grimbal
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Re: Heaven and Hell
« Reply #11 on: Jun 10th, 2007, 3:14pm » |
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I wonder.
If a compulsive liar knows that you know he is a liar, wouldn't he tell the truth to deceive you?
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Archae
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Re: Heaven and Hell
« Reply #12 on: Jun 10th, 2007, 3:16pm » |
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However, Sir Col, wouldn't the truth-telling guard want to do the same (meaning reveal his true truth-telling nature)? If that is the case, by trying to avoid giving any information, the lying guard would give him/herself away. So the real question is if the guards want to hide/reveal their true natures, or if they want to prevent/help your finding the door to Heaven. It seems that one of those two motivations would drive their responses.
Also, if God is a benevolent being, would s/he give you a riddle that would be unsolvable depending on two laymen guards? I think not. A real riddle has a solution - so I think the guards would answer yes or no to the best of their abilities, since the Big Cheese seemed to imply that their responses (not only the question) would be yes-or-no.
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| « Last Edit: Jun 10th, 2007, 3:17pm by Archae » |
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Sir Col
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Re: Heaven and Hell
« Reply #13 on: Jun 11th, 2007, 12:08am » |
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on Jun 10th, 2007, 3:14pm, Grimbal wrote:I wonder.
If a compulsive liar knows that you know he is a liar, wouldn't he tell the truth to deceive you? |
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That is the unavoidable contradiction of being a liar. By telling lies I am being true to my nature, but by being deceptive about my nature I must tell the truth. Whichever way I am being honest in some respect.
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Sir Col
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Re: Heaven and Hell
« Reply #14 on: Jun 11th, 2007, 12:12am » |
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on Jun 10th, 2007, 3:16pm, Archae wrote:| Also, if God is a benevolent being... |
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I think that we've ruled that possibility out in this riddle. If "god" were to assess our suitability for heaven based on our intellect then that would make him quite malevolent. I am certain that that sort of god would employ the most sophisticated liar and truth tellers possible for this task.
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| « Last Edit: Jul 1st, 2007, 11:33am by Sir Col » |
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Grimbal
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Re: Heaven and Hell
« Reply #15 on: Jun 11th, 2007, 1:23am » |
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Anyway, God being by definition almighty, He/She cannot be benevolent.
Almighty implies God has no limitation whatsoever in what God can do. Benevolent means God will not do things that are bad or unfair to humans. This is a contradiction.
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towr
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Re: Heaven and Hell
« Reply #16 on: Jun 11th, 2007, 2:41am » |
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on Jun 11th, 2007, 1:23am, Grimbal wrote:| Almighty implies God has no limitation whatsoever in what God can do. Benevolent means God will not do things that are bad or unfair to humans. This is a contradiction. |
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How is that a contradiction? There are tons of things I could do which I won't.
And "no limitation whatsoever" is overstating omnipotence in my opinion; logic is always a limitation. "No physical limitations" seems more in place.
In any case, religious concerns are not in the spirit of the riddle.
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Archae
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Re: Heaven and Hell
« Reply #17 on: Jun 11th, 2007, 3:06am » |
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God gives you the riddle to get into Heaven because s/he is aware that you like riddles. Sounds to me like God is trying to be nice... or ironic. It depends on if you succeed ornot I suppose.
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rmsgrey
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Re: Heaven and Hell
« Reply #18 on: Jun 11th, 2007, 7:15am » |
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One of my favourite occurrences of this riddle is in the movie Labyrinth, where a pair of door guards explain to the heroine that one of them always lies, and the other always tells the truth, and that one door leads to her destination while the other doesn't (or something like that - it's been a while...)
Sarah figures out the riddle, but doesn't stop to consider whether she can trust the guards' explanation, and ends up confidently walking into a trap...
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Grimbal
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Re: Heaven and Hell
« Reply #19 on: Jun 11th, 2007, 8:12am » |
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Yeah. If it is one of the guards who tells her that exactly one guard lies, it has to be taken into account.
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rmsgrey
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Re: Heaven and Hell
« Reply #20 on: Jun 12th, 2007, 9:02am » |
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on Jun 11th, 2007, 8:12am, Grimbal wrote:| Yeah. If it is one of the guards who tells her that exactly one guard lies, it has to be taken into account. |
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Actually, as I recall, it's a joint effort between both guards to explain the rules...
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Domna
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Re: Heaven and Hell
« Reply #21 on: Jun 14th, 2007, 10:15am » |
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on May 28th, 2007, 7:05pm, KjSlag wrote:| Because you like riddles, after you die God decides to give you a riddle to decide your fate. He puts you in a room in which there are two doors and two guards. One door leads to Heaven, and the other to Hell. One guard always tells the truth, the other always lies. God tells you that you may ask one guard one yes or no question. The guard will then answer the question (keep in mind that one of the guards will lie and you don't know which one will lie). Then you must walk though one of the doors. Your goal is obviously to walk though the door that leads to Heaven. What question will you ask in order to know for sure which door leads to Heaven? |
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I think you need to pay attention to the fact that he states you may ask one guard one yes or no question. It does not mean you cannot ask the guard an open ended question.
Ask: Are you a guard?
Answers:
(1) "Yes."
Then ask: "Which is the door to heaven?" This one will be the truth teller so you can trust his answer.
(2) "No."
Then ask the other guard: "Which is the door to heaven?" You ask the other one because he could either say that the opposit door is the door to heaven or that neither door leads to heaven.
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| « Last Edit: Jun 14th, 2007, 10:50am by Domna » |
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Noke Lieu
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Re: Heaven and Hell
« Reply #22 on: Jun 14th, 2007, 9:48pm » |
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on May 28th, 2007, 7:05pm, KjSlag wrote:. God tells you that you may ask one guard one yes or no question. (snip)
What question will you ask in order to know for sure which door leads to Heaven? |
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That leaves imperatives. Yay.
You will tell me which door... 
Alternatively, grab the guard and walk through the door with them...
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Three Hands
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Re: Heaven and Hell
« Reply #23 on: Jun 15th, 2007, 5:21am » |
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For grabbing the guard, I'm sure he won't mind heading through the door with you. I mean, it's not as if he has to stay at the eventual destination...
Either that or he knows that if he leaves the entrance lobby guard duty gig, he's heading straight to Hell regardless of the door he goes through, so he's not going to budge if he can help it...
Of course, the real problem you face is that the Devil, who contractually has a part in the forming of such an important test as this, has neglected to tell the guards which door leads where...
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alien2
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Re: Heaven and Hell
« Reply #24 on: Jun 15th, 2007, 11:55am » |
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You ask no question. You just peek through one of the doors. And if the guard tries to stop you, then the guard is evil, meaning that you have chosen the doors leading to Heaven. 
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