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Unexpected hanging paradox

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Re: Unexpected hanging paradox

#31

Post by aekotra »

aekotra wrote: post #30

The prisoners reasoning is wrong. > if he hasn't been hanged by Thursday, there is only one day left - and so it won't be a surprise if he's hanged on Friday. This belief is FALSE. The moment of surprise for a Friday hanging takes place at 12pm on Thursday. Of course, this also happens to be the moment of surprise for a Thursday hanging. In other words, at 11:59am on Thursday he will not know if his hanging takes pla…

> Despite significant academic interest, there is no consensus on its precise nature and consequently a final correct resolution has not yet been established.

This is, frankly, embarrassing.

Re: Unexpected hanging paradox

#32

Post by [deleted] »

aekotra wrote: post #30

The prisoners reasoning is wrong. > if he hasn't been hanged by Thursday, there is only one day left - and so it won't be a surprise if he's hanged on Friday. This belief is FALSE. The moment of surprise for a Friday hanging takes place at 12pm on Thursday. Of course, this also happens to be the moment of surprise for a Thursday hanging. In other words, at 11:59am on Thursday he will not know if his hanging takes pla…

[deleted]

Re: Unexpected hanging paradox

#33

Post by incompatible »

aekotra wrote: post #30

The prisoners reasoning is wrong. > if he hasn't been hanged by Thursday, there is only one day left - and so it won't be a surprise if he's hanged on Friday. This belief is FALSE. The moment of surprise for a Friday hanging takes place at 12pm on Thursday. Of course, this also happens to be the moment of surprise for a Thursday hanging. In other words, at 11:59am on Thursday he will not know if his hanging takes pla…

"He will not know the day of the hanging until the executioner knocks on his cell door at noon that day."

The wording of the problem is everything.

Re: Unexpected hanging paradox

#34

Post by vignesh_m »

aekotra wrote: post #30

The prisoners reasoning is wrong. > if he hasn't been hanged by Thursday, there is only one day left - and so it won't be a surprise if he's hanged on Friday. This belief is FALSE. The moment of surprise for a Friday hanging takes place at 12pm on Thursday. Of course, this also happens to be the moment of surprise for a Thursday hanging. In other words, at 11:59am on Thursday he will not know if his hanging takes pla…

The main issue is the definition of surprise for perfectly rational entities. Your argument doesn't really add much as you can just fix that time of day when all executions occur, and you've just restated the paradox.

Re: Unexpected hanging paradox

#35

Post by aekotra »

vignesh_m wrote: post #34
aekotra wrote: post #30

The prisoners reasoning is wrong. > if he hasn't been hanged by Thursday, there is only one day left - and so it won't be a surprise if he's hanged on Friday. This belief is FALSE. The moment of surprise for a Friday hanging takes place at 12pm on Thursday. Of course, this also happens to be the moment of surprise for a Thursday hanging. In other words, at 11:59am on Thursday he will not know if his hanging takes pla…

The main issue is the definition of surprise for perfectly rational entities. Your argument doesn't really add much as you can just fix that time of day when all executions occur, and you've just restated the paradox.

The main issue is not the definition of surprise. The main issue is given to you plainly: the prisoner's reasoning is wrong.

I encourage you to give an example where the execution times are changed and I guarantee you it will suffer from the same assumptive traps as the original "paradox".

Re: Unexpected hanging paradox

#37

Post by everybodyknows »

jzwinck wrote: post #23

There is a surprise on Thursday (if not before). If the prisoner is alive on Thursday at noon he will either be surprised to find he is to be hanged on Thursday, or surprised to find it will be Friday. Before that he had 50% expectation for either, and there is bound to be a negative surprise with regard to one day and a positive surprise for the other.

Right, so if we suppose that the "punch-line" statement, describing the prisoner's state of mind, is true:

> the executioner knocks on the prisoner's door at noon on Wednesday — which, despite all the above, was an utter surprise to him.

Then it follows there are two false epistemological claims in the text. First by the judge:

>He will not know the day of the hanging until the executioner knocks on his cell door at noon that day.

This is false, as you correctly reason, since a knock on Friday would come as no surprise (at the time it occurred).

The second false claim, this time by the narrator, reinforces the first:

>Everything the judge said came true.

Not every claim the judge asserted was tested by the recounted physical events: There was no knock on Friday.

Re: Unexpected hanging paradox

#38

Post by p1esk »

aekotra wrote: post #31
aekotra wrote: post #30

The prisoners reasoning is wrong. > if he hasn't been hanged by Thursday, there is only one day left - and so it won't be a surprise if he's hanged on Friday. This belief is FALSE. The moment of surprise for a Friday hanging takes place at 12pm on Thursday. Of course, this also happens to be the moment of surprise for a Thursday hanging. In other words, at 11:59am on Thursday he will not know if his hanging takes pla…

> Despite significant academic interest, there is no consensus on its precise nature and consequently a final correct resolution has not yet been established. This is, frankly, embarrassing.

He will not know the day of the hanging until the executioner knocks on his cell door at noon

Did you miss that line?

Embarrassing indeed...

Re: Unexpected hanging paradox

#39

Post by robocat »

jzwinck wrote: post #23

There is a surprise on Thursday (if not before). If the prisoner is alive on Thursday at noon he will either be surprised to find he is to be hanged on Thursday, or surprised to find it will be Friday. Before that he had 50% expectation for either, and there is bound to be a negative surprise with regard to one day and a positive surprise for the other.

> 50% expectation for either

Incorrect. Not getting hanged is also a solution, which doesn't allow induction.

Re: Unexpected hanging paradox

#40

Post by aekotra »

p1esk wrote: post #38
aekotra wrote: post #31

Earlier quoted context omitted.

> Despite significant academic interest, there is no consensus on its precise nature and consequently a final correct resolution has not yet been established. This is, frankly, embarrassing.

He will not know the day of the hanging until the executioner knocks on his cell door at noon Did you miss that line? Embarrassing indeed...

I don't follow. Can you please explain? I am very aware of that line.
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