Conundrum

Technology — By Matthew Tommasi on 23 April 2009 9:42 pm

I heard this conundrum on my way home the other day (on the train) while listening to a certain podcast.

After hearing the ‘answer’ it took me a little while to get my head around it. I was quite impressed by it.

Pretend you have died, your soul has left your body and you arrive at two gates. The gate to Heaven is guarded by one guard, and the gate to Hell is guarded by another guard.

Both guards are identical. Both gates are identical. You don’t know which gate leads to Heaven and which gate leads to Hell.

You can pass through any gate at any time, but once you do, you can’t turn back. You could either spend eternity in Heaven, or spend eternity in Hell. So choose wisely..

The only thing you do know, is that the guard outside the gate to Heaven ALWAYS tells the Truth, and the guard outside the gate to Hell ALWAYS tells lies.

You are only allowed ONE question to ask.

Obviously you want to get into Heaven, so what question do you ask?

For example, lets say you ask, “Is this the gate to Heaven?”

The guard outside heaven always tells the truth and answers, “Yes, this is the gate to Heaven, come through..”

The guard outside hell always tells lies and answers, “Yes, this is the gate to Heaven, come through..”

Based upon the guards answers, how do you know who is telling the truth and who is lying? Both guards are identical and both gates are identical.

Remember the only thing you do know is that the guard at the gate to Heaven always tells the truth.. and the guard at the gate to Hell always tells lies. You only have one question you can ask.

Let’s say you asked.. “Will I go to Heaven?”

The first guard outside Heaven truthfully answers, “Yes you will, come through..”

The second guard outside Hell lies and says, “Yes you will, come through..”

Or you asked the question, “Are you telling the Truth?”..

The first guard outside Heaven truthfully answers, “Yes I am, come through..”

The second guard outside Hell lies and says, “Yes I am, come through..”

and so on…

Can you think of a question to ask, that will provide you with the answer to proceed through the correct gate into Heaven?

The answer to this riddle would be to ask,

“If I was to ask the other guard what gate they were guarding.. what would they say?”

The guard outside Heaven always tells the truth.. he knows that the guard outside Hell would LIE and say ‘Heaven’.. so Heaven’s guard truthfully answers “HEAVEN”

The guard outside Hell always lies.. he knows that the guard outside Heaven would tell the Truth and say ‘Heaven’.. so Hell’s guard lies and replies “HELL”

Asking this question reveals the correct gate to which each guard is guarding..

Tags: conundrum, gates, heaven, hell, pearly, puzzle, question, riddle