Aristotle

One of the main problems for Aristotle’s view of an immobile earth is that of planetary retrogression. Within the ‘Two Sphere Universe’ view, the approximation is that the aether sphere is perfect in matter and in motion.

Aether is said to have a uniform movement and does not deviate from its natural motion. Aristotle’s other theories of violent and constrained motion (his rudimentary physics), rely on this view of aether being perfect. Historically, his view was widely held creditable by the astronomical community at the time. Within this aether substance, were stars that were fixed points of pure aether, and moving stars which we now know as the planets. In the centuries leading up to Aristotle’s time, Babylonian astronomers recorded observations of the Planets and there existed a pattern to which these wandering stars adhered to (Kuhn p47). This was also considered to be Uniform and perfect motion in Aristotle’s theory as they supposedly were in the aet...