History : Mar-Apr 2019
ublished in 1543, Copernicus’s life’s work preserves a key tenet of medieval cosmol- ogy: The universe is formed of spheres, each one nested within another. Starting with this underly- ing assumption, Copernicus constructed his theories based not only on mathematics but also on philosophy. Even heliocentricity was influenced by the belief that a central fire animated the whole universe, which was formulated by a follower of the sixth-century b.c. phi- losopher Pythagoras. The primacy of the sun and its centrality to classical thought is eloquently invoked by Copernicus. In Book I of his great work, he wrote: “Then in the middle of all stands the Sun. For who, in our most beautiful temple, could set this light in a better place than that from which it can illuminate the whole? Not unfittingly do some call it the light of the world, others the soul. Tremigistus calls it the visible God; Sophocles’ Electra, the All-seer. And in fact does the sun, seated on his royal throne, guide his family of planets as they circle round him.” CENTERED ON THE SUN SITTING AT THE CENTER, THE SUN ILLUMINATES EIGHT CELESTIAL SPHERES IN COPERNICUS’S MODEL OF THE UNIVERSE.