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A comment on Seven Puzzles You Think You Must Not Have Heard Correctly (2006) [pdf]. Parent comment

Re:Seven Puzzles You Think You Must Not Have Heard Correctly... by tiglionabbit on Monday August 29, 2016 @05:01PM (#12385277)
If two people have blue eyes, "Somebody has blue eyes" is not new information, because everyone has already seen that someone has blue eyes.
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Re:Seven Puzzles You Think You Must Not Have Heard Correctly... by fenomas on Tuesday August 30, 2016 @08:09AM (#12389266)
It's not new information to either person individually. But while both people already knew it, they didn't know that the other one knew it. That's the new information.
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Re:Seven Puzzles You Think You Must Not Have Heard Correctly... by x1798DE on Monday August 29, 2016 @05:34PM (#12385552)
> If two people have blue eyes, "Somebody has blue eyes" is not new information, because everyone has already seen that someone has blue eyes.

The new information in that scenario is that the other guy with blue eyes knows that someone has blue eyes.

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Re:Seven Puzzles You Think You Must Not Have Heard Correctly... by tiglionabbit on Monday August 29, 2016 @10:10PM (#12386958)
If they have seen someone with blue eyes they would already know that.
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Re:Seven Puzzles You Think You Must Not Have Heard Correctly... by JoeAltmaier on Tuesday August 30, 2016 @10:34PM (#12395583)
They know that you know that. That's the new info.
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