So i was solving exercises in propositional logic lately and stumbled upon a puzzle, that goes like this:
Each inhabitant of a remote village always tells the truth or always lies. A villager will only give a "Yes" or a "No" response to a question a tourist asks. Suppose you are a tourist visiting this area and come to a fork in the road. One branch leads to the ruins you want to visit; the other branch leads deep into the jungle. A villager is standing at the fork in the road. What one question can you ask the villager to determine which branch to take?
I intuitively guessed the answer is "If I asked you this path leads to the ruins, would you say yes?". So my questions are:
- What is the name and/or source of this logical riddle?
- How can i corroborate my answer with mathematical rigor?