There is a wise money-giver who knows the answer to every question in the infinite set of possible questions except for one. If you ask him any question he knows the answer to, he will tell you. If you prove to him that you are able to ask him the unanswerable question¹ he will produce \$1,000,000 and give it to you. If, however, you ask him a question he does know the answer to but you then amass more than $1,000,000 without that money coming from him you die in exactly 5 minutes.

What can you ask him to gain $1,000,000 and live a normal life span?

¹ The wording "unanswerable question" is not a hint.

  • 2
    $\begingroup$ Wait until you are less than five minutes from death... $\endgroup$
    – Dr Xorile
    Mar 19, 2017 at 16:47

3 Answers 3


It seems like

What is the question whose answer you don't know?

will do the trick.

Either that is itself the "unanswerable question", in which case you get the money as soon as you ask him; or it isn't, in which case he will answer it and then you can ask him the question he tells you and get the money.

But it also seems like

this answer is far from unique. For instance, you could ask "How can I get $1M from you without dying prematurely?" and then do what he says. (He might tell you the "unanswerable question" in response to that -- or maybe he might tell you some other way of persuading him to give you money.)

  • $\begingroup$ Wow, the people here are good. Also, regarding the other smile questions: I am considering them to be different wordings of the same question. $\endgroup$
    – john01dav
    Mar 18, 2017 at 1:53
  • $\begingroup$ The problem with this strategy is that if you are only allowed one guess, you are not guaranteed to get the money. What if the question the money-giver doesn't know the answer to happens to be "What is 2+2?" He might know the question (and reveal it to you) but not know its answer. If you're only allowed one guess, you're out of luck. $\endgroup$
    – DyingIsFun
    Mar 18, 2017 at 2:01
  • $\begingroup$ @Silenus The question makes it clear (I think) that you are allowed more than one guess. $\endgroup$
    – Gareth McCaughan
    Mar 18, 2017 at 11:15
  • $\begingroup$ Even if you are allowed to ask more than one question, another reason to favor a single question strategy is to avoid potentially taking on the risk of 5-minute dying, should you ever amass a million dollars on your own. $\endgroup$
    – DyingIsFun
    Mar 18, 2017 at 12:05

If you want an easy buck, you can ask the wise money-giver:

What is the answer to the question that you do not know?

After all,

there's nothing in the rules against referring to this question or its answer in the question itself. Plus—by definition—the money-lender won't know the answer to it. You are guaranteed to get the money asking this single question.


My question would be:

What's the answer to the unanswerable question?

Or, if referring to it doesn't do it,

Is this statement is false true?

Why it works?

The "What is the answer to the unanswerable question" will epsilon-reduce to "What is the answer to "What is the answer to ..."" with ω times the question repeated


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