Definitely a repost, but it fits the season

  • CodexArcanum@lemmy.dbzer0.com
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    3 months ago

    That would be the symbol\operation called TRUE or TOP or “tautology” which is always true. They’re actually missing quite a few of the weirder ops, including implication and biconditional\iff\if-and-only-if. (Edit: Actually I think XNOR is also the biconditional. I guess pretend like I said “material implication” and “reverse implication”. Fricken booleans man!)

      • CodexArcanum@lemmy.dbzer0.com
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        3 months ago

        I truly have no idea and wish I did, haha. It looks like a shorthand for which operation is being followed, maybe like a group theory thing, but I really don’t know.

    • NeatNit@discuss.tchncs.de
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      3 months ago

      I never got why “implies” is called that. How does the phrase “A implies B” relate to the output’s truth table?

      I have my own “head canon” to remember it but I’ll share it later, want to hear someone else’s first.

      • Excel@beehaw.org
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        3 months ago

        “A implies B” means if A is true then B must be true; if A is false, then B can be anything. In other words, the only state not allowed is A being true and B being false. Therefore, the only “hole” is the part of A that doesn’t include B.

      • Speiser0@feddit.org
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        3 months ago

        “A → B” is true in any variable assignment where B is true if A is true.

        It has always been mostly obvious to me.