“Medieval people thought the Earth was flat”

The idea that medieval Europeans largely believed the Earth was flat is a persistent misconception, but it is indeed a myth. This erroneous notion gained significant traction in the 17th century, largely propagated by Protestants seeking to discredit Catholic teachings by portraying the Middle (Review) Ages as a period of scientific ignorance. It was further cemented in popular culture during the 19th century by influential authors such as Washington Irving, whose fictionalized biography of Christopher Columbus depicted him as challenging church authorities over the Earth's shape. In reality, the debate surrounding Columbus's voyage was not about whether the Earth was round, but rather its circumference and the feasibility of reaching Asia by sailing west.

In truth, the knowledge of Earth's spherical shape was well-established among educated individuals long before the medieval period. Ancient Greek scholars, including Pythagoras in the 6th century BC and Aristotle around 330 BC, provided compelling evidence for a round Earth through observations like ships disappearing hull-first over the horizon and the Earth's curved shadow during lunar eclipses. Furthermore, Eratosthenes famously calculated the Earth's circumference with remarkable accuracy around 240 BC. This understanding was not lost during the Middle Ages; prominent medieval scholars like the Venerable Bede and Thomas Aquinas explicitly affirmed the Earth's sphericity, and this knowledge was widely taught in universities across Europe.

The enduring belief in this myth stems from a combination of factors. The dramatic narrative of a lone explorer defying ignorant religious dogma is more engaging than the historical reality. Moreover, the 19th-century polemical histories that popularized the myth served to frame a perceived conflict between science and religion, contributing to the idea that the "Dark Ages" were devoid of scientific inquiry. This convenient historical distortion continues to be a common, yet inaccurate, shorthand for a supposedly unenlightened past.