War Prisoner
Logic puzzles require you to think. You will have to be logical in your reasoning.
During the first world war, there was a prisoner who had been captured. When brought to the army headquarters, the prisoner was told that he had a choice to remain silent or say something. He was also told that if he did say something, he would be shot if he spoke the truth or hanged if he had lied. The war prisoner did in fact make a single statement; he said only a phrase and they had to let him go unscathed. What did the prisoner say to get out free?
Answer
The prisoner told them: "You will hang me."
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Comments
sackonto
Oct 11, 2002
 He could also make the statement, "I only tell lies." 
Rowsdower
Jan 10, 2004
 Coudn't the people at HQ just say, "Whoops. We messed up!" and shoot him anyway? Just kidding, and fun teaser. 
lallu_21
Mar 25, 2004
 he could also say "hi....how are you" 
rose_rox
Nov 01, 2005
 I've never fully understood the logic of these kinds of teasers. 
metallicman
Nov 14, 2005
 I agree rose rox. If he told the truth, he would be shot. If he lied, hanged. it is totally impossible to not tell the truth AND not tell a lie. 
MadDog72
Mar 19, 2006
 Here is an explanation:
He says 'I will be hanged'. If it is true, he will be shot, but that makes his statement false, as he is shot, not hanged. Since his statement is false, he cannot be shot; instead, he will be hanged. But if he is hanged, that makes his statement true, so he will be shot, not hanged. In other words, if the statement is true, then it is false; if it is false, then it is true. It is a paradox and is therefore neither true or false, so he is released.
A simpler version of this paradox, known as the 'Epimenides paradox', is 'This statement is false'. This statement cannot be true, for if it were true, it would state that it is false, and it cannot be both true and false. Similarly, if it were false, then its negation must be true, which states that it is true. But again, it cannot be both true and false.
Another interesting variation of this paradox is: ' "yields falsehood when preceded by its quotation" yields falsehood when preceded by its quotation.' This is interesting because it doesn't use selfreference.
This is also similar to the concept which Kurt Godel used to prove the famous Incompleteness Theorem, which shows that there are always unprovable statements in mathematics. The statement he used roughly translates to 'This statement cannot be proven'. 
jntrcs
Mar 29, 2006
 What about an opionionated statement? 
bradon182001
May 28, 2010
 I'm more confused with that explanation. LOL 
cwjakesteel
Jun 22, 2011
 I understand.
He could have said, "You will hang me"
or
"You will not shoot me"
Any action done by the jailors would be wrong by their own terms.
UNLESS, they shoot and hang him at the same time. 
kegbernal
Nov 16, 2011
 I get it 
kegbernal
Nov 16, 2011
 I get it 
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