• CanadaPlus@lemmy.sdf.org
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    21 days ago

    Yeah, OP seems to be assuming a continuous mapping. It still works if you don’t, but the standard way to prove it is the more abstract “diagonal argument”.

    • jsomae@lemmy.ml
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      2 days ago

      But then a simple comeback would be, “well perhaps there is a non-continuous mapping.” (There isn’t one, of course.)

      “It still works if you don’t” – how does red’s argument work if you don’t? Red is not using cantor’s diagonal proof.