A young man walks through the forest. He comes to a bridge. In front of the bridge is a large man carrying an axe.
The man says, “If you want to cross this bridge, you must tell me a statement. If I think the statement is true, you will be strangled to death. If I say the statement is false, your head will be chopped off.”
A few minutes later, the young man walked over the bridge, while the larger man stood pondering. What was the statement the young man had given?
Answer
The man said, “My head will be chopped off.”
If the man said the statement was false, the young man’s head would be chopped off, making the statement true.
If the man said the statement was true, the young man would be strangled to death, thus making it false.