Eratosthenes calculated the circumference of the Earth in ancient Greece using nothing but a stick, some shadows, and basic geometry, proving the planet was round thousands of years ago.

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Eratosthenes calculated the circumference of the Earth in ancient Greece using nothing but a stick, some shadows, and basic geometry, proving the planet was round thousands of years ago. While modern internet conspiracy theorists struggle to understand basic physics, this guy looked down a well in Syene, measured the angle of a shadow in Alexandria, and casually deduced the size of the globe with staggering accuracy. He basically hired a guy to walk the distance between the two cities just so he could do his math homework properly. The fact that an ancient librarian figured out planetary dimensions while wearing a toga makes the modern flat-earth movement look even more phenomenally embarrassing. He essentially dismantled a global conspiracy before it even existed using literal dirt and sunlight, making him the patron saint of aggressively outsmarting stupid people!