How to Use Zorn's Lemma (2008)

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28 points | by perihelions 6 days ago ago

4 comments

  • hopfenspergerj 2 days ago ago

    We might as well use the axiom that “you can make arbitrary choices at each stage of a transfinite induction”. It’s mostly pedagogical tradition to make students translate that into one of the classical forms of Choice in their proofs.

    • dullcrisp 2 days ago ago

      Does transfinite induction without the ability to make arbitrary choices make sense? Or is the axiom just that you can do transfinite induction?

    • seanhunter 2 days ago ago

      Zorn's lemma is specifically that there is a maximal element of an ordered set that is structured in a specific way. That seems a lot weaker to me than just being able to make a completely arbitrary choice. Am I wrong about that?

      • toodlemcnoodle a day ago ago

        You are correct that it SEEMS that way. They are, in fact, equivalent under traditional mathematical hypotheses about how sets work.