Geocentrism

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Geocentrism


In geocentric worldviews, the earth is the center of the universe. The ancient Greek philosopher Aristotle (384322 b.c.e.) thought of celestial bodies as beautiful and pure, travelling on the surface of perfect spheres, and of the earth as an imperfect place that had fallen to the center of the universe. In the second century b.c.e., Ptolemy adjusted the geocentric theory with epicycles (orbits imposed on the orbits of the planets) and eccentrics (orbits that were centered to the side of the universe) so that the theory was better able to predict the orbits of the sun, moon, and stars. The geocentric view of the universe was replaced by the heliocentric (suncentered) view that was pioneered by Nicolaus Copernicus (14731543), adopted and defended by Galileo Galilei (15641642), and much refined by Johannes Kepler (15711630), who discovered the elliptical nature of planetary orbits.


See also Anthropocentism; Cosmology, Physical Aspects; Galileo Galilei

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