Geocentric model wasn't until Kepler demonstrated a physical observation that could show that the physical sun is directly involved in determining an orbit that a new model was required. The Ptolemaic order of spheres from Earth outward is: Ptolemy did not invent or work out this order, which aligns with the ancient Seven Heavens religious cosmology common to the major Eurasian religious traditions. It also follows the decreasing orbital periods of the moon, sun, planets and stars. Muslim astronomers generally accepted the Ptolemaic system and the geocentric model, but by the 10th century texts appeared regularly whose subject matter was doubts concerning
Trading Places He explains that this axiom asserts its importance not in the fact that "our time" sees an increased expectation of new operas being developed but, rather, in the fact that there is an increased expectation of "new productions of operas." Cavell draws a comparison of themes between "Trading Places" and the opera "The Marriage of Figaro", stating that "what "Trading Places" wants from its reference to "Figaro" is mostly the idea of resourceful and sociable young and poor overcoming with various disguises the conniving of the unsociable old and rich but with no sense that the old may be redeemed