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Re:Arrow's Theorem (2014) by Iv on Saturday November 11, 2017 @03:40AM (#15675528)
So, if some of you have felt despair at the idea that this may indicate that true democracy is impossible, fear not: it hinges on the fact that some preferences can be cyclic: A wins over B who wins over C, who wins over A.

These situations are possible but rare and in such a case, it is arguable that all potential winners are legitimate.

Re:Arrow's Theorem (2014) by fny on Saturday November 11, 2017 @04:29PM (#15678286)
Arrows theorem is misleading because it only applies to rank order systems.

Range voting (i.e. 0-5 rating system) satisfies all the criteria. [0] So yes, democracy is theoretically possible.

[0]: https://youtu.be/e3GFG0sXIig

Re:Arrow's Theorem (2014) by macawfish on Sunday November 12, 2017 @01:58AM (#15680008)
Good video, thanks for sharing that!
Re:Arrow's Theorem (2014) by Judgmentality on Saturday November 11, 2017 @04:23AM (#15675611)
Yep, this is when you have non transitive properties. A really cool embodiment of this same concept is non transitive dice.

https://en.wikipedia.org/wiki/Nontransitive_dice

Re:Arrow's Theorem (2014) by baddox on Saturday November 11, 2017 @06:19AM (#15675893)
Indeed, a non-transitive election like that means that there is no Condorcet winner. Some voting methods (including first past the post) are guaranteed to select a Condorcet winner if one exists, but when one doesn’t exist (if A>B>C>A), various voting methods will result in various winners.

I love reading about the theory behind voting methods, but one common criticism is that these edge cases are rare and thus a pure theoretical approach isn’t sufficient for getting a “desirable” (however you define that) outcome.

https://en.wikipedia.org/wiki/Condorcet_method