this post was submitted on 06 Oct 2024
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While I know this is supposed to be a joke, surely the angles of a shape must be on the inside of the shape.
Eh, going back when I was learning proofs in high school...
A square was 4 equal length sides arranged in two sets of parallel lines with four 90° right angles.
Two sets of parallel lines are necessary to make a rectangle, and a square is just a rectangle with equal sides.
Proofs are all about working the way through each step to getting to a distinct shape defined by those smaller steps. All squares are rectangles, but not all rectangles are squares. Technically if in remembering correctly, rectangles are also trapezoids, just with 90° right angles.
Parallelograms, not trapezoids. Kind of. Maybe. Or maybe trapeziums.
See… some define trapezoid as specifically one set of parallel sides (originally trapezium). Some as no parallel sides (originally trapezoid) Those two were swapped by some asshole, and then swapped back in England but not in America.
Though most now just say a trapezoid (or trapezium in England) is at least one set of parallel sides, which makes parallelograms a type of trapezoid. Which does make a rectangle a type of trapezoid.
They call only one pair of parallel sides a proper trapezoid instead.
I totally forgot that parallelograms were a thing in all that. And I never even considered naming differences over time.
Lol
I just read another comment here pointing out that square is a polygon, which requires having only straight lines.
I think this would be a stronger argument.
I'm not aware of any shape that is defined by the angles of its outsides.
I think what the previous poster is saying is that the image does not have four 90° angles, but instead it has two 90° and two 270° angles.
...I have no idea if that's an actual deal breaker, but the logic is sound.
I suspect these lines are straight on a sphere. What we're seeing is a square on a projected sphere.