When the facts change, I change my mind. What do you do, sir?
—John Maynard Keynes
Arguably the most famous mistake in the history of science, geocentrism – the belief that the earth is the center of the universe – held sway in the West from ancient Greece until the late 16th century. This erroneous conviction was supported by basic but misleading sensory observations (to the human eye, the sun appears to revolve around the earth, while the ground beneath us feels stationary), as well as by many religious traditions, including Judeo-Christianity. It took the combined work of the astronomers Copernicus, Galileo, and Kepler – plus about a century and a half of sluggish belief change – for the correct, heliocentric model of the solar system to become broadly accepted.