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Truth, lies and pot luck


Best Answer araver, 30 January 2013 - 09:39 PM

Spoiler for perhaps
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17 replies to this topic

#11 bonanova

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Posted 31 January 2013 - 11:41 AM

araver has it. Nice solve. No lie.


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
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#12 k-man

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Posted 31 January 2013 - 05:46 PM

Spoiler for perhaps

Spoiler for That's pretty clever, but it seems like cheating...


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#13 bonanova

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Posted 31 January 2013 - 05:57 PM

Spoiler for That's pretty clever, but it seems like cheating...

 
Spoiler for Not really how else is there a solution

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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#14 CaptainEd

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Posted 31 January 2013 - 06:02 PM

I see k-man's point: if the randomizer is really indifferent to whether his/her answer is true or false, then why would he/she be "forced by the paradox to evaluate the truth value..." Why not just flip the coin? There's no requirement that the randomizer actually knows the truth or falsity of his/her answer.

 

I'm reminded of an old Superboy episode (yes, way old...) where a special kind of Kryptonite made Superboy into Pinocchio--whenever he lied, his nose grew longer. Superboy used this to figure out where the bad guys were hiding, by uttering the words "the bad guys are North of Main Street". When his nose grew longer, he knew that the bad guys were actually South of Main Street. This was an odd theory of "lying"--saying something that doesn't happen to be true, even though you don't know it. But our randomizer could be this way.

 

(Actually, I generally interpret one of these "randomizers" as being more like Maxwell's daemon--he does something pathological, whatever will best thwart your intended theory)

 

Now Bonanova's answer has come in. OK, I can bear that interpretation--the randomizer makes an explicit choice between lying and telling the truth. Having made that choice, he/she figures out what IS the truth, and then tells the truth or lies. Humph.

 

Yes, having a unanimous crowd is very pleasing!


Edited by CaptainEd, 31 January 2013 - 06:07 PM.

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#15 bonanova

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Posted 31 January 2013 - 06:29 PM

Some solvers were discussing questions to which R could not respond.

What door would you choose in that case?

 

araver's approach is a solution, in that R can not respond erroneously. ;)


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- Bertrand Russell

#16 Prime

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Posted 31 January 2013 - 11:44 PM

Let me offer the following perspective:

Spoiler for Undecidable Proposition

 


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Past prime, actually.


#17 k-man

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Posted 01 February 2013 - 09:28 PM

Let me offer the following perspective:

Spoiler for Undecidable Proposition

 

Thanks, Prime. That's an interesting perspective...So, I've been mulling this over in my head trying to convince myself that everything is correct, so here is a slightly different perspective...

Spoiler for

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#18 Prime

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Posted 02 February 2013 - 12:35 AM

Let me offer the following perspective:

Spoiler for Undecidable Proposition

 

Thanks, Prime. That's an interesting perspective...So, I've been mulling this over in my head trying to convince myself that everything is correct, so here is a slightly different perspective...

Spoiler for

I see there is some ambiguity in my example - not deterministic enough.

Let me try again:

Spoiler for Disambiguation


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Past prime, actually.





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