Since the beginning of human civilization, people have tried to describe the way the world works, some fundamental truths that can explain why things are as they are. Many ancient worldviews have been suggested, such as Parmenides' which says that change is illusory or the Pythagoreans' numerical perfection. However, one view that persisted well into the middle ages was Aristotle's, whose empirical descriptions provided the conceptual framework for much of the later scientific development. Many …showed first 75 words of 1526 total…

…showed last 75 words of 1526 total…cosmos. Aristotle's spheres were composed of quintessence, a fifth element not found on earth whose properties did not change. This shows that although the methods and rationale behind Greek astronomy were different, the basic assumptions of uniform circular motion and saving the phenomena were consistent. References: Osler, University of Calgary, HTST 477.01 Class Lecture Notes, Fall 2003. Lindberg, D. C. 1992, The Beginnings of Western Science, The University of Chicago Press, United States of America, pages 46-68, 89-104.