[rookie1ja]

Honestants and Swindlecants III. - Back to the Logic Problems
Our gringo displeased the sovereign with his intrusive questions and was condemned to death. But there was also a chance to save himself by solving the following logic problem. The gringo was shown two doors - one leading to a scaffold and the second one to freedom (both doors were the same) and only the door guards knew what was behind the doors. The sovereign let the gringo put one question to one guard. And because the sovereign was an honest man he warned that exactly one guard is a Swindlecant.
What question can save the gringo's life?

Classic wording:
Two Doors
You are travelling down a country lane to a distant village. You reach a fork in the road and find a pair of identical twin sisters standing there. One of the sisters always tells the truth and the other always lies.
If you are allowed to ask only one question to one of the sisters to find the correct road to the village, what is your question?

Spoiler for Solution:

Honestants and Swindlecants III. - solution
There are a few types of questions:

Indirect question: „Hey you, what would the other guard say, if I asked him where this door leads?“ The answer is always negated.

Tricky question: „Hey you, does an honestant stand at the door to freedom?“ The answer will be YES, if I am asking an honestant who is standing at the door to freedom, or if I am asking a swindlecant standing again at the same door. So I can walk through the door. A similar deduction can be made for negative answer.

Complicated question: „Hey you, what would you say, if I asked you ...?“ An honestant is clear, but a swindlecant should lie. However, he is forced by the question to lie two times and thus speak the truth.

[pooky64]

Tricky question: „Hey you, does an honestant stand at the door to freedom?“ The answer will be YES, if I am asking an honestant who is standing at the door to freedom, or if I am asking a swindlecant standing again at the same door. So I can walk through the door. A similar deduction can be made for negative answer. I dont understand how this question works... unless you explain that the honest one stands at the door to freedom...

[rookie1ja]

Quote

Tricky question: „Hey you, does an honestant stand at the door to freedom?“ The answer will be YES, if I am asking an honestant who is standing at the door to freedom, or if I am asking a swindlecant standing again at the same door. So I can walk through the door. A similar deduction can be made for negative answer. I dont understand how this question works... unless you explain that the honest one stands at the door to freedom...

If the answer is YES:
Only honestant standing at the freedom door or swindlecant staying at the freedom door can say it.
So you go through that door.

If the answer is NO:
Only honestant standing at the wrong door or swindlecant staying at the wrong door can say it.
So you go through the other door.

[fosley]

The Indirect question is the simplest in my mind (I came up with that solution a long time ago). I think it's also the original solution, and I know it's the one given in The Labyrinth. I think I've come up with the Complicated question on my own, but I'm not sure about that. Either way, it would work.

I hadn't ever heard of the Tricky question, so I had to figure it out. After some fiddling, I came up with this:

---Freedom-------Death
1. H=Yes----------S=No
2. S=Yes----------H=No

You have the freedom door on the left and the death door on the right. In scenario 1, the Honestant (H) stands in front of the freedom door, and the Swindlecant (S) stands in front of the death door. Since the true answer to the question is "yes", the Honestant will answer "yes" and the Swindlecant will answer "no".

In scenario 2, the roles are reversed. Since the correct answer is "no", the Swindlecant will say "yes" and the Honestant will say "no". As you can see from the chart, the only way either one can say "yes" is if they are standing in front of the Freedom door, and the only way either one can say "no" is if they are not.

This is exactly what you said, but I added a visual example for reference (that's what it took for me to figure it out to begin with).

[paultholen]

Yoo, new here, isn't the simplest question: "Do you know what is behind your door?"

If it was already posted, sorry wasn't very thorough in reading the other posts...

[fosley]

I don't think that would work. It would tell you who was who, but wouldn't tell you which door is which.

[Fenix]

What if you asked a guard "Which door would the other guard would want me to pick?"

The honestant guard would point to the door leading to the scaffold; and the Swindlecant would point to the same door, but that is assuming that the honestant doesn't want to see you die.

[larryhl]

Quote

What if you asked a guard "Which door would the other guard would want me to pick?"

The honestant guard would point to the door leading to the scaffold; and the Swindlecant would point to the same door, but that is assuming that the honestant doesn't want to see you die.

Fenix, that's the indirect question, only you said it in plainer English

[Numenor]

Now doesn't this remind you of that old short-story called "The Lady or the Tiger?"

The only answer I can understand would be the indirect question (I saw that several weeks ago on NUMB3RS as well, for those of you who watch it).

Numenor

[normdeplume]

The indirect question makes sense and I agree with it.

The Tricky question logic looks flawed to me, unless I am missing something. the question asked is 'Hey you, does an honestant stand at the door to freedom' Whilst your conclusions are correct as to the answers you will get, nothing actually indicates whether you are talking to an honestant or a swindlecant, So the conclusion you draw is that a honestant is standing in front of the door to freedom, but you still don't know which of the 2 is the honestant.

Is it me?