Riddle: Win One Rep by Answering this Riddle

[Rev. Rye]

Ask the one on the left:

"If I asked the other guy what was behind his door, what would he say?"

The liar would say the other guy would say he had the tiger.
The honest one would say he would say he had the check.

This was on an episode of Doctor Who (The Tom Baker years) and The Ricky Gervais Show.

[Faith No More]

Oh, do be fair. Where is this thread? Do you have a link to it?

http://atheistforums.org/thread-35944.ht...gence+test

I'm actually the one that first brought it up with a video from the movie "Labyrinth." Do I get a rep for that?

[drfuzzy]

Do we get a rep for reading the responses, since the question has been answered?  I liked Kingpin & Magi's answers, but Iroscato probably should get a rep for all the hard work!

[Rhondazvous]

I would ask both:

"If I asked you which door leads to the check, which one would you point to?"

Wouldn't work as they can both show their own doors. You have to ask each guard what the other one's reply would be to which door is the correct one.

Basically

D1 - G1 - tells lie
D2 - G2 - tells truth

Assume D1 is the correct door

Ask each guard which door the other guard will show:

In case of G1(liar):       G2 will point to D1 hence G1 will lie and point to D2
In case of G2(honest):  Will correctly say that G1 will point to D2.

So you just have to do the opposite to both and enter D1.

This only works if you assume both guards know of each other's honesty or dishonesty.

It would work if you only ask one. The key word is "always." One guard always tells the truth. The other always lies. They can't do otherwise.

[Rhondazvous]

I read the first page of the other thread. It's not quite the same question and you can't get the right answer to my question based on it. So I'm giving out reps as promised. I'll give reps to the whistle blowers too for their love of fairness. No reps for reading but I'll give everyone a kudos. .

[Faith No More]

I read the first page of the other thread. It's not quite the same question and you can't get the right answer to my question based on it. So I'm giving out reps as promised. I'll give reps to the whistle blowers too for their love of fairness. No reps for reading but I'll give everyone a kudos. .

The OP isn't the same, but you'll see that I brought the riddle up in the third post. It was subsequently brought up and answered two more times in that thread.

You're giving out reps for cheating!

[Catholic_Lady]

For one rep and to be induction into the Rhondazvous International Hall of Geniuses, answer the following riddle. One rep for the answer and one more rep for why that answer works.

There are two doors. Both doors are identical except behind one door is a check for 10 thousand dollars. Behind the other door is a man-eating tiger. In front of each door stands a guard. Each guard is exactly identical except one guard always tells the truth while the other guard always lies. To find out which door has the check you get to ask one guard one question. What question will you ask to which guard?

The question I would ask:  "If I asked what door lead to freedom, what door would the other guard point to?"

If you asked the truth-guard, the truth-guard would tell you that the liar-guard would point to the door that leads to death.
If you asked the liar-guard, the liar-guard would tell you that the truth-guard would point to the door that leads to death.
Therefore, no matter who you ask, the guards tell you which door leads to death, and therefore you can pick the other door.

This. 
Though I probably never would have figured it out lol. Freaking genius.

[Rhondazvous]

I read the first page of the other thread. It's not quite the same question and you can't get the right answer to my question based on it. So I'm giving out reps as promised. I'll give reps to the whistle blowers too for their love of fairness. No reps for reading but I'll give everyone a kudos. .

The OP isn't the same, but you'll see that I brought the riddle up in the third post.  It was subsequently brought up and answered two more times in that thread.  

You're giving out reps for cheating!

Oh, but that's impossible. Kingphil is a Christian. Christians don't cheat.

Defend your honor, sir!

[Kingpin]

The OP isn't the same, but you'll see that I brought the riddle up in the third post.  It was subsequently brought up and answered two more times in that thread.  

You're giving out reps for cheating!

Oh, but that's impossible. Kingphil is a Christian. Christians don't cheat.

Defend your honor, sir!

It's the classic knives/knaves.  The caveat is that word "always".  If it were sometimes, your probability would be 50%, but because one "always" lies and the other "always" tells the truth, you will know the correct answer by asking one guard what the other will say about a specific door.

[Rhondazvous]

The question I would ask:  "If I asked what door lead to freedom, what door would the other guard point to?"

If you asked the truth-guard, the truth-guard would tell you that the liar-guard would point to the door that leads to death.
If you asked the liar-guard, the liar-guard would tell you that the truth-guard would point to the door that leads to death.
Therefore, no matter who you ask, the guards tell you which door leads to death, and therefore you can pick the other door.

This. 
Though I probably never would have figured it out lol. Freaking genius.

Ooh, I'ma tell. You're cussing on the sly.