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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 something. If I think your statement is true, I will strangle you to death. If I think your statement is false, I will chop off your head."

A few minutes later, the young man walks over the bridge, while the larger man stands pondering.

What did he say?

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closed as too broad by Rand al'Thor, xnor, Len, Gamow, Haobin Feb 20 '15 at 14:32

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

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    $\begingroup$ I'm voting to close as "too broad". There are way too many workable answers. $\endgroup$ – Rand al'Thor Feb 19 '15 at 23:39
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    $\begingroup$ Please put your answer into an answer rather than in the body of the question. $\endgroup$ – Josh Caswell Feb 20 '15 at 3:55
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    $\begingroup$ Maybe you should ammend it to: You must tell me a statement which I can evaluate to true or false. - Otherwise you can just ask him a question, or tell him "Beagles!" - are Beagles true or false??? - The statement should at least be required to be a true/false statement... $\endgroup$ – Falco Feb 20 '15 at 11:34
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    $\begingroup$ Flippant answer: the man with the axe is under no obligation to ensure his statement is true and he is obviously a very disturbed individual. Clearly the correct thing to do is to give him a philosophical lecture on the nature and value of life asking him to consider his life choices in just murdering people who want to cross a bridge. You need to convince him to not be a murderer... $\endgroup$ – Chris Feb 20 '15 at 14:44
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    $\begingroup$ So why isn't the answer "I have a bomb on a deadman's switch"? $\endgroup$ – Joshua Jun 11 '15 at 20:37
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The canonical answer:

You will chop off my head.

But this doesn't really work because

he can simply strangle you and then behead your corpse.

So perhaps

You will kill me by chopping off my head.

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    $\begingroup$ You got it in the last guess. I'll explain. $\endgroup$ – bgmCoder Feb 19 '15 at 23:34
  • $\begingroup$ What if you live after he chops off your head? $\endgroup$ – Abraham Zhang Feb 20 '15 at 6:28
  • $\begingroup$ @EpicGuy You can still bite him... $\endgroup$ – Lyrion Feb 20 '15 at 8:48
  • $\begingroup$ Haha! "C'mon then! I'll bite ye to death!" $\endgroup$ – bgmCoder Jun 14 '15 at 0:29
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    $\begingroup$ He can just kill you by splitting your skull and then chop off your head after you are dead - your statement was false and he chopped off your head, so no contradiction $\endgroup$ – Falco Apr 13 '16 at 12:22
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How about the classic paradoxical statement:

This statement is false.

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  • $\begingroup$ This is what I thought when first reading the puzzle. $\endgroup$ – Robert Columbia May 30 '18 at 1:55
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How about:

"Snaaaaaa!"

Which is a statement in my made up language...

He can ponder all day if it is false or true and will never know ^^

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He said:

if you were me what would you say?

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Answer:

The young man said, "My head will be chopped off."

Explanation:

If the axeman claimed the statement was false, the young man's head would be chopped off, making the statement true.

But if..

But if the axeman claimed the statement was true, the young man would be strangled to death, which would make the statement false.

Summary:

In the end, the axeman came to a bridge he could not cross. He couldn't say the young man's statement was true OR false without invalidating his question.

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