Originally Posted by bungalowbill357
You could ask the guard who always tells the truth
"Which door will the other guard tell me is rigged with explosives?"
The truthful guard will tell you the one he is guarding, knowing that the other guard would lie.
Oh yes, I typed that out wrong! You walk through the one he says the other one says is rigged with explosives.
BungalowBill was right, I got it the wrong way around. You ask which one the other guard would say is rigged with explosives and either way, the door which you are told will be the one without explosive. That's because you're either being told a lie truthfully, or being lied to about an honest answer (makes sense?)