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        riddles >> easy >> Life and death
        
(Message started by: DeMark on Sep 26^th, 2004, 10:46am)

Title: Life and death
Post by DeMark on Sep 26^th, 2004, 10:46am

There was a medieval court where 2 pieces of paper would be given to the defendant: "Life" is written on the first one, and "Death" on the second. You could choose.
Well, there was a man who knew that the judge hates him, and he found out that the word "death" will be written on the both notes.
The next day, he wasn't executed. Knowing what is written on the notes, what did he do to save himself?

Title: Re: Life and death
Post by rmsgrey on Sep 26^th, 2004, 11:14am

Picks one note and ::[hide]turns over the other[/hide]::

Title: Re: Life and death
Post by towr on Sep 26^th, 2004, 11:16am

Just like the evil mayor and the farmer(?)'s girl

Title: Re: Life and death
Post by mathunter on Oct 6^th, 2004, 4:11am

eat that paper ;D

Title: Re: Life and death
Post by John_Gaughan on Oct 6^th, 2004, 6:51am

on 09/26/04 at 11:16:32, towr wrote:

Just like the evil mayor and the farmer(?)'s girl

I think it was the miller's daughter. Anyway, I looked up the thread after reading this the first time, and never did find a definitive answer to the riddle. This one confuses me too. How does rmsgrey's answer work?

Title: Re: Life and death
Post by towr on Oct 6^th, 2004, 10:38am

inference.

If the one I didn't pick shows "Death", I must have picked the one with "Life". Unless neither show "Life", but then it would be clear someone cheated.

Title: Re: Life and death
Post by John_Gaughan on Oct 6^th, 2004, 1:30pm

What if the one you don't pick shows "Life"? Then you die, right?

Title: Re: Life and death
Post by rmsgrey on Oct 6^th, 2004, 1:49pm

It's stated in the riddle that both pieces of paper are known (by the prisoner) to have "death" on them. Since the rules of the court require the two words to each appear on one piece of paper, revealing that the paper he didn't choose had"death" leaves the cheating judge with a choice between revealing himself as a cheat (since he would only object if he knew the papers were wrong) or letting the man go free. Of course, the man could also demand that both pieces of paper be examined by an impatial witness but that doesn't let him go free.

Title: Re: Life and death
Post by John_Gaughan on Oct 6^th, 2004, 10:17pm

Ah, I was also thinking of the evil mayor and the miller's daughter. In that riddle, the daughter did not know if the mayor was cheating or not. In this case the judge is. towr made it sound like the same reasoning works for this riddle as well, and I am not sure that it does. Maybe I am missing something, I don't know.

Title: Re: Life and death
Post by towr on Oct 6^th, 2004, 11:10pm

In the other riddle the girl tries to make it more fair, and the same reasoning works there.
Either the mayor didn't cheat, and showing the token you did not pick doesn't change the probability of either outcome. Or he did cheat and you reversed the outcome on him.

Title: Re: Life and death
Post by John_Gaughan on Oct 7^th, 2004, 6:04am

I see, the same method works, but not to the same ends (proving the judge cheating, making the mayor's contest more fair). For some reason this did not make sense at first, but it does now. The riddles are more about spectators' perceptions than anything -- showing people whether or not the contest is rigged, forcing the judge/mayor to play fair.