In a faraway mountain sits an old monastery where three monks protect the secret of a famous treasure. These monks are very wise understanding all languages, but they speak in their own strange language of two words: HAA and MAA.
Here’s what you’ve figured out:
- One word stands for “YES” and the other for “NO” (you don’t know which is which yet)
- One monk always tells the truth
- One monk always lies
- One monk can lie or tell the truth at random (you can’t predict them)
- You don’t know which monk behaves in which way
To reach the treasure, you need to solve two important puzzles, and the monks are the only ones who can help.
- Figure out their words – What word stands for “YES” and which one means “NO”?
- Spot the truth-teller – Who is the monk that never lies?
After solving both, you can ask the truthful monk to guide you to the treasure.
The Task
You get to ask the monks questions, but keep in mind:
- They reply with either “HAA” or “MAA”
- The liar always says the opposite of the truth
- The random monk might give any answer true or false, without a pattern
- Be sure of your findings before going after the treasure
Do you think you can come up with a plan to crack their language and uncover the honest monk?
What would you ask, and how would you decide the order of questions?
Hint
Try to come up with questions where you can guess how different kinds of monks would respond, no matter what the words mean.
View the answer
SOLUTION:
Step 1: Start With a Self-Referential Question
You need to frame a question that lets you figure out the truth even if you’re unsure about the meanings of the words.
Ask any monk: “If I were to ask you ‘Are you the truth-teller?’, would your response be HAA?”
Breaking down this layered question:
If HAA translates to YES:
- Truth-teller: Says HAA when asked “Are you the truth-teller?” because they always tell the truth.
- Liar: Lies about being the truth-teller answering NO but then flips their answer so they also say HAA.
- Unpredictable: Could respond with either HAA or MAA without any clear pattern.
If HAA translates to NO:
- Truth-teller: If asked “Are you the truth-teller?” they would say yes. Their response would be MAA so they answer MAA.
- Liar: If asked “Are you the truth-teller?” they would lie and say no. But since they also lie about their own answer, they still end up saying MAA.
- Unpredictable: They could answer either HAA or MAA without any consistent logic behind it.
The main idea here: Both the truth-teller and the liar give the exact same response to this kind of self-referential question. The unpredictable one however, might choose .
When you ask this question to the three monks, two of them will match in their answers (the truth-teller and the liar), while the unpredictable monk will provide a different answer. The matching answers will also help you figure out the language they are using:
- If the truth-teller and liar say HAA then HAA means YES.
- If they both say MAA then HAA stands for NO.
Step 2: Figure Out Who the Truth-Teller Is
Once you figure out the language, ask each monk a question where you already know the correct answer.
Here’s a good example: “Are you standing on the ground?” (or something else easy to verify on your own).
Breakdown:
- The truth-teller uses the word that means YES.
- The liar always uses the word that means NO.
- The unpredictable monk could say either one.
If a monk answers “YES,” that monk is either the truth-teller or the unpredictable monk. But a monk who says “NO” can be the liar.
Step 3: Find the Truth-Teller
To figure out if the suspected truth-teller is the truth-teller ask them another simple and clear question like: “Is the sky above us?”
If they answer “YES” again, they are the truth-teller. If their response is “NO,” then they were the unpredictable monk. At that point, you should ask the other monk, the one who said “YES” earlier, and test them instead.
Step 4: Ask for Treasure Directions
After figuring out who tells the truth, you can ask them where the treasure is. Use the language key you found earlier to understand their HAA/MAA responses.
A Smarter Shortcut:
You can solve this puzzle faster by asking each monk just one tricky question:
Ask them: “If I asked you ‘Does HAA mean YES?’ would you reply HAA?”
This question works as a clever double-negative, which means:
- The truth-teller always gives a steady response about what they would say.
- The liar lies about their own answer, which leads to a double-negative. This makes their reply match the truth-teller’s.
- The unpredictable monk answers randomly without any pattern.
The two monks who give matching answers are the liar and the truth-teller. The one with the different response is the random-answer monk. Their shared response also reveals the language being used. For example, if they say “HAA,” you know HAA means YES.
Next, ask a simple and obvious question to figure out which one of the consistent answerers is the truth-teller and which is the liar.