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by avz 3964 days ago
> One of the consequences of this axiom is that every subset of the real numbers has a least element according to some ordering.

An even weirder consequence of AC is the Banach-Tarski paradox [1].

Other examples of how mathematicians come up with alternative perspectives are non-Euclidean geometries that replace the parallel postulate of the common Euclidean geometry, e.g. Lobachevskian [2] and Riemannian geometry [3].

[1] https://en.wikipedia.org/wiki/Banach%E2%80%93Tarski_paradox

[2] https://en.wikipedia.org/wiki/Hyperbolic_geometry

[3] https://en.wikipedia.org/wiki/Elliptic_geometry