[andyfox]

Actually, flat earth is a good example, but in a different way: it is a myth that both intelligent and less intelligent people felt the earth was flat.

With extraordinarily few exceptions no educated person in the history of Western Civilization from the third century B.C. onward believed that the earth was flat.

A round earth appears at least as early as the sixth century BC with Pythagoras, who was followed by Aristotle, Euclid, and Aristarchus, among others in observing that the earth was a sphere. Although there were a few dissenters, by the time of Eratosthenes, followed by Strabo and Ptolemy, the sphericity of the earth was accepted by all educated Greeks and Romans.

Nor did this situation change with the advent of Christianity. A few early Christian fathers denied the sphericity of earth by taking passages from the Bible as geographical rather than metaphorical statements. On the other side tens of thousands of Christian theologians, poets, artists, and scientists took the spherical view throughout the early, medieval, and modern church. No educated person believed otherwise.

Historians of science have been proving this point for at least 70 years (most recently Edward Grant, David Lindberg, Daniel Woodward, and Robert S. Westman).