• emergencyfood@sh.itjust.works
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    1 day ago

    you cannot prove a system using the system.

    Doesn’t that only apply for sufficiently complicated systems? Very simple systems could be provably self-consistent.

    • Shelena@feddit.nl
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      1 day ago

      It applies to systems that are complex enough to formulate the Godel sentence, i.e. “I am unprovable”. Gödel did this using basic arithmetic. So, any system containing basic arithmetic is either incomplete or inconsistent. I believe it is still an open question in what other systems you could express the Gödel sentence.

    • Björn@swg-empire.de
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      1 day ago

      I think it’s true for any system. And I’d say mathematics or just logic are simple enough. Every system stems from unprovable core assumptions.