• Kogasa@programming.dev
    link
    fedilink
    English
    arrow-up
    3
    ·
    4 个月前

    Nobody is practically concerned with the “incompleteness” aspect of Gödel’s theorems. The unprovable statements are so pathological/contrived that it doesn’t appear to suggest any practical statement might be unprovable. Consistency is obviously more important. Sufficiently weak systems may also not be limited by the incompleteness theorems, i.e. they can be proved both complete and consistent.

    • bitfucker@programming.dev
      link
      fedilink
      English
      arrow-up
      2
      ·
      4 个月前

      Oh, what if the Riemann hypothesis is such a statement then? Or any other mathematical statement. We may not have any use for them now, but as with all things math, they are sometimes useful somewhere unexpected.

      • Kogasa@programming.dev
        link
        fedilink
        English
        arrow-up
        1
        ·
        4 个月前

        It’s extremely unlikely given the pathological nature of all known unprovable statements. And those are useless, even to mathematicians.

        • bitfucker@programming.dev
          link
          fedilink
          English
          arrow-up
          1
          ·
          4 个月前

          Math is also used to make a statement/model our universe. And we are still trying to find the theory to unify quantum mechanics and gravity. What if our math is simply inconsistent hence the theory of everything is not possible within the current mathematical framework?

          Sure when you are solving the problems it is useless to ponder about it, but it serves as a reminder to also search for other ideas and not outright dismiss any strange new concept for a mathematical system. Or more generally, any logical system that follows a set of axioms. Just look at the history of mathematics itself. How many years before people start to accept that yes imaginary numbers are a thing.

          • Kogasa@programming.dev
            link
            fedilink
            English
            arrow-up
            2
            ·
            4 个月前

            Dunno what you’re trying to say. Yes, if ZFC is inconsistent it would be an issue, but in the unlikely event this is discovered, it would be overwhelmingly probable that a similar set of axioms could be used in a way which is transparent to the vast majority of mathematics. Incompleteness is more likely and less of an issue.

    • weker01@feddit.de
      link
      fedilink
      English
      arrow-up
      2
      ·
      4 个月前

      I think the statement “this system is consistent” is a practical statement that is unprovable in a sufficiently powerful consistent system.

      Can you help me understand the tone of your text? To me it sounds kinda hostile as if what you said is some kind of gotcha.

      • Kogasa@programming.dev
        link
        fedilink
        English
        arrow-up
        1
        ·
        4 个月前

        Just explaining that the limitations of Gödel’s theorems are mostly formal in nature. If they are applicable, the more likely case of incompleteness (as opposed to inconsistency) is not really a problem.