The math nerds are having a field day! In topology, a "clopen" set is both closed AND open simultaneously - it's the mathematical equivalent of being bisexual but for sets! 🤓
The empty symbol (∅) represents a set that's both open and closed under any topology, making this the ultimate mathematical identity crisis. Poor medieval lady doesn't realize she's talking to a mathematical paradox that refuses to be put in a box!
Next time someone asks if you're this or that, just declare yourself a clopen set and watch their brain short-circuit faster than a calculator dividing by zero!