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Topic: Maximisation problem
Replies: 10   Last Post: Jul 27, 2013 6:16 AM

 Messages: [ Previous | Next ]
 Paul Posts: 780 Registered: 7/12/10
Re: Maximisation problem
Posted: Jul 27, 2013 6:11 AM

On Saturday, July 27, 2013 10:57:11 AM UTC+1, Peter Percival wrote:
> pepstein5@gmail.com wrote:
>

> > On Saturday, July 27, 2013 12:36:32 AM UTC+1, Peter Percival wrote:
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> >> Paul wrote:
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> >>
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> >>> Let n be a fixed integer > 1. n logicians walk into a bar. The
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> >>
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> >>> barwoman says "Do all of you want a beer?" The first logician says
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> >>
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> >>> "I don't know." The second logician says "I don't know." ... The
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> >>
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> >>> n-1st logician says "I don't know." The nth logician says "Yes
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> >>
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> >>
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> >>
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> >> That doesn't answer the question correctly.
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> > ...
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> >
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> > Please could you state your objection? Everyone is narrowly focusing on the yes/no question: "Do all of the n logicians want a beer?" Everyone saying "I don't know" clearly wants a beer because, if they didn't want a beer, they would know that not everyone wants a beer and would answer "no" instead of "I don't know."
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> > The nth logician follows the above reasoning and also wants to drink beer, so says "yes".
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> >
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> It isn't clear to me that "I don't know" actually means "I do, but I
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> cannot peak for my fellows." It may be that "I don't know" is short for
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> "I don't know, I'm still thinking about it." Or it may be that "I don't
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> know" is short for "I do but Robinson is in our party and he always
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> takes 10 minutes to make his mind up."

quasi eloquently addressed precisely this style of objection. It my also be the case that none of the logicians want to buy beer at all. Perhaps they had all intended to go to a shoe shop, but they have a terrible sense of direction. They also can't hear very well either. So when the barwoman said "Do all of you want a beer?", they thought she said "Do you all want to be here?" The first two said "I don't know". Originally, they had thought they were in a shoe shop, but now they are becoming unsure. Maybe it's a shoe shop disguised as a bar, or maybe it actually is a bar and they're in the wrong place. The final logician is wrongly convinced it is a shoe shop, so gives an affirmative answer.

Paul Epstein

Date Subject Author
7/26/13 Paul
7/26/13 Richard Tobin
7/26/13 Peter Percival
7/27/13 Paul
7/26/13 Peter Percival
7/27/13 Paul
7/27/13 quasi
7/27/13 Paul
7/27/13 quasi
7/27/13 Peter Percival
7/27/13 Paul