• yetAnotherUser@discuss.tchncs.de
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    9 hours ago

    Yes there is:

    Only men like nothing.

    Explanation:

    “Only XYZ like ABC” is equivalent to: “Everyone who likes ABC is also an XYZ.”

    Since everybody likes at least something, there is no one who likes nothing. The statement: “Everyone who likes nothing is also a man” is true because the “Everyone who likes nothing” part results in 0 people. And it’s true to say that everyone in a group of 0 people is a man. It’s also true that everyone in a group of 0 people is not a man.

    But other than vacuous truths, no sentence stating “Only man like XYZ” is true.

      • yetAnotherUser@discuss.tchncs.de
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        3 hours ago

        This woman likes set theory because she was involved in a set theory workshop:

        https://dmg.tuwien.ac.at/sandramueller/conferences/

        But you’re kind of right that it’s not great that math is still a strongly male dominated field. There is not a single woman’s name in the Wikipedia article for set theory, where I first tried to find a counterexample.

        Also, you don’t necessarily need set theory to arrive at vacuous truths. Logic is enough:

        FALSE => [statement]

        Still, I think vacuous truths are fun because they are meaningless. Especially because they have to be considered in math or else your carefully constructed proof becomes invalid.