At work we somehow landed on the topic of how many holes a human has, which then evolved into a heated discussion on the classic question of how many holes does a straw have.

I think it’s two, but some people are convinced that it’s one, which I just don’t understand. What are your thoughts?

  • ccunning@lemmy.world
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    1 year ago

    How many holes does a rubber band have? A donut?

    Topologically a rubber band, a donut, and a straw have the same number of holes. The hole at either end of the straw is just a continuation of the same one hole.

    • wanderingmagus@lemmy.world
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      1 year ago

      Take that cylinder and stretch it until it’s a cube with two square cutouts in it. Stretch in some of the inner walls. Now you have a house, with a door and a window. Now: does the house have two holes - a door and a window - or does it have one hole?

      • Th4tGuyII@kbin.social
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        1 year ago

        A straw’s “in” and “out” are completely arbitrary. You can flip a straw either way and it’d still work.

        Anything with a hole through it that isn’t perfectly 2D could have a “in” and “out” side. Your rubber band your doughnut only don’t have one because nobody ever thought to define one.