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WM was thinking very hard :
They are erroneously called countable, but they are not countable.Only finite sets are countable.Wrong, it is countable if there is a bijection.
It does not make it wrong, but it unmasks it at imprecise. That's why I don't like it. We can do better.But all "countably" infinite sets have the same size, which according to the different numbers of elements is a very unsharp measure.That you don't like cardinal arithmetic, doesn't make cardinal arithmetic wrong.
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