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Unanswerable multiple choice question

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11–20 of 59 posts

Re: Unanswerable multiple choice question

#11
post #7
post #6

Earlier quoted context omitted.

But then you're implying that you'll get a correct answer 1/2 of the time, which means that the answer is B, but then the answer is correct only 1/4 of the time, and you've got yourself in an infinite loop.

[deleted]

[deleted]

Re: Unanswerable multiple choice question

#13

Appears to be a clever case of the first incompleteness theorum.

Gödel's first incompleteness theorem states that any effectively generated theory capable of expressing elementary arithmetic cannot be both consistent and complete. In particular, for any consistent, effectively generated formal theory that proves certain basic arithmetic truths, there is an arithmetical statement that is true, but not provable in the theory (Kleene 1967, p. 250) per http://en.wikipedia.org/wiki/Gödels_incompleteness_theorems

Just because you title something an "Unanswerable question" doesn't mean it actually is, and certainly doesn't mean the first incompleteness theorem is relevant.

Re: Unanswerable multiple choice question

#14
post #7
post #6

Earlier quoted context omitted.

But then you're implying that you'll get a correct answer 1/2 of the time, which means that the answer is B, but then the answer is correct only 1/4 of the time, and you've got yourself in an infinite loop.

[deleted]

If the correct answer is 50% then there needs to be 2 possible answers of 50%, otherwise picking randomly will only result in that answer being selected 25% of the time, rendering the "correct" answer false.

Re: Unanswerable multiple choice question

#15
post #7
post #6

Earlier quoted context omitted.

But then you're implying that you'll get a correct answer 1/2 of the time, which means that the answer is B, but then the answer is correct only 1/4 of the time, and you've got yourself in an infinite loop.

[deleted]

"... then in the long run half of the time you will hit on the right answer"

So the right answer would be B, but you only have 25% chance of choosing that ... infinite loop.

Re: Unanswerable multiple choice question

#18

Appears to be a clever case of the first incompleteness theorum.

Gödel's first incompleteness theorem states that any effectively generated theory capable of expressing elementary arithmetic cannot be both consistent and complete. In particular, for any consistent, effectively generated formal theory that proves certain basic arithmetic truths, there is an arithmetical statement that is true, but not provable in the theory (Kleene 1967, p. 250) per http://en.wikipedia.org/wiki/Göd…

Is "The above question has no solution", which is choice C, not a Godel sentence?

Re: Unanswerable multiple choice question

#20
post #15
post #7

Earlier quoted context omitted.

[deleted]

"... then in the long run half of the time you will hit on the right answer" So the right answer would be B, but you only have 25% chance of choosing that ... infinite loop.

...an infinite loop, so no chance of answering correctly - C.
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