The flat-Earth myth and Columbus
Educated Europeans never forgot the Earth was round. The argument with Columbus was about its size, and he was wrong.
"Then we got stupid for hundreds of years"?
Partly true, but not about the shape of the Earth. After Eratosthenes, educated people in Europe and the Islamic world never lost the knowledge that the Earth is a sphere. Medieval scholars like the Venerable Bede (700s) and Thomas Aquinas took it for granted, and the standard medieval astronomy textbook was literally called On the Sphere (Sacrobosco, around 1230). Kings held an orb, a globe, as a symbol of their rule.
Columbus
The famous story that Columbus had to prove the world was round against people who thought he'd sail off the edge is a myth. It was popularized by Washington Irving's romantic 1828 biography of Columbus, and later spread in the 1800s.
The real argument in 1492 was about size. Columbus claimed Asia was only about 2,400 miles west of the Canary Islands. He did this by choosing the smallest available estimate of the Earth and the largest estimate of how far Asia stretched east. The experts, who knew Eratosthenes' figure, said the distance was far greater and no ship could carry enough food and water. They were right. Columbus survived only because an unknown continent was in the way. He died insisting he had reached Asia.
What did get worse
What medieval Europe did lose for centuries was a lot of Greek science in general, which was preserved and extended by scholars in the Islamic world and came back through Arabic translations. And on the question of whether the Earth moves, the Church's resistance was real. See Copernicus and Bruno and Galileo.
Key facts
- Educated medieval Europeans knew the Earth was round
- The Columbus flat-Earth story was popularized by Washington Irving, 1828
- The real 1492 dispute was the Earth's size; Columbus underestimated it and the experts were right