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Re:The Point of the Banach-Tarski Theorem – not just a curio... by reagency on Sunday June 07, 2015 @02:20PM (#9675755)
The reason those things are strange is that uncountable sets have absolutely no bearing on computable objects (== enduring in math and science) but everyone mistakenly applies their countable intuition to uncountable set theory.
Re:The Point of the Banach-Tarski Theorem – not just a curio... by black_knight on Sunday June 07, 2015 @06:58PM (#9676635)
If one uses classical logic there are even many countable, even finite sets which are beyond computable distinction. The set of computable functions on say natural numbers is a countable set, but even distinguishing when two such are equal cannot be effectively done.

The solution is either to distinguish between countable and enumerable and decidable, or to use intuitionistic logic.