Questions tagged [paradox]
A puzzle in which a seemingly impossible situation is presented, or any sort of construction that results in a logical contradiction.
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Sleeping Beauty's evaporating certainty
I thought of a little puzzle while contemplating the Sleeping Beauty problem.
The puzzle: create a variant of the Sleeping Beauty experiment (which involves one fair coin toss) where there is a ...
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Roulette Paradox
I have not seen the following simple paradox anywhere. Maybe most people are so smart that for them it isn't a paradox at all, but I think it is worth identifying.
Is it a "puzzle"? Well, is ...
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Help-paradox: an infinite chess puzzle
In this chess puzzle, the ruleset involves a now-obsolete version of the 3rep draw rule, in which draw is declared upon three consecutive instances of the same series of moves. More precisely, if ...
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Football Pass Rate Paradox [closed]
There are 2 teams - Team A and Team B. Both teams play 2 matches. In both matches, Team A has a higher pass rate than Team B. Can the overall combined pass rate for Team B be higher than that of Team ...
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Explain this incorrect proof that 3=0
Consider the quadratic equation $x^2+x+1=0$.
$x=0$ is not a solution to this equation, so it is safe to divide both sides by $x$.
$x+1+\frac{1}{x}=0$
Rearrange:
$x+1=-\frac{1}{x}$
And substitute into ...
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Is this a solution to the unexpected hanging paradox?
I once wrote an answer to Unexpected hanging paradox that went something like this
"In the context of the unexpected hanging paradox, being hung by surprise is defined to mean he couldn't deduce ...
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a simple paradox [closed]
This is probably the simplest paradox out there and it still confuses me, here it is.
The sentence below is true.
The sentence above is false.
I've known about this one for a few years and it has ...
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Is the unexpected hanging paradox really a paradox? [duplicate]
The unexpected hanging is described in the Wikipedia article Unexpected hanging paradox.
A hanging is said to be a surprise of on the morning that the prisoner is hanged, he cannot deduce that he ...
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Omnipotence Paradox [closed]
God has limitless power. So can he/she create a stone so heavy the no one lift it ? If yes, then god himself/herself can not lift it, so limited power. If no, then there's a limit to what god can ...
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Death cause Paradox [closed]
In the sentence:
"Two guys killing themselves by jumping out of a roof"
What is the actual death cause? the roof or themselves?
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The faster you walk
The faster you walk, the quicker you'll get there, it's true. But be warned, it's not without a price, for the faster you go, the further you'll have to walk before you arrive.
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Average of a Series [closed]
The "average" of a series is x. A new data point comes in with the value x + 1.
But the new average is less than ...
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I exist, but I do not. I change, but I do not
I am a tool but I do not really exist
I am always used, even when I am not
The people that truly benefit from me are those that have trouble using me
I am found everywhere, but I haven't always ...
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How many tries to roll a 6?
Suppose you roll a (fair, 6-sided, perfectly ordinary) die repeatedly until you roll a 6. As is well known, the expected (i.e., long-term average over many trials) number of rolls required is 6.
Now ...