A man is traveling to a town and comes to a fork in the road. If he goes left, he goes to the liars' village. If he goes right, he then goes to the village of truths - which is where he wants to go. However, he does not know which way is which.
He doesn't have time to go both routes, so he approaches a stranger who is standing in the middle of the fork. The stranger is from one of the villages, but what he doesn’t know about that stranger is that he either speaks the truth or lies. However, the man goes up to the stranger and asks him one question. He now knows which path leads to the village of truths after he answered.
Can you figure it out what the man asked the stranger?
The man asks the stranger to point the path back to his own village. If he is from the village of truths, he’ll be pointing at his own village which is where he wants to go. But if he is not, he’ll still be pointing at the same village because he wants to give a dishonest answer.
So, either way will work and he’ll just have to take the path where the stranger is pointing at.