Thursday, May 14, 2009

The stuck-in-the-dungeon riddle

Okay, smarty pants.

You are stuck in a dungeon with two doors. One leads to freedom, the other to death. You may ask just one single question of the two guards standing by the doors in order to escape. One of the men always lies and the other always tells the truth, but you can't differentiate the liar from the truth-teller.

What one question can you ask that will guarantee your exit through the right door?

Give it some thought before you scroll down to the answer . . .

you are so cheating . . .

Give up? By the way I wonder if the dungeon has rats . . .

. . . or Iron Maidens. Haha. Okay here's the answer:

The question you'd ask either guard is, "If I had asked you if this was the door to freedom, would your answer have been 'yes'?" If it was the honest guard, it's a no brainer. If it was the liar guard, he'd have to lie about what his original answer would have been. Voila.

I love that riddle.

1 comment:

Kelly said...

the answer I've always had was to ask, "Which door would the other person have told me led to freedom?"

Both point to the nonfreedom door.