Hales of miletus (625-547bce: pre-socratic philosopher, attempted to explain natural phenomena without reference to mythology, using rational explanations, using unique physical causes for events in nature, thought water was the fundamental element. Anaximander: natures has impersonal laws (rather than g-ds revenge, thought universe was cyclical. Pythagoras (& followers: perceived relation between arithmetic ratios & harmonize intervals in music, numbers were the basis for all things, recognized that earth was a sphere, shadow of the earth on moon during eclipse is circular. Plato, aristotle: his teacher was socrates and his most famous student was aristotle, they laid the foundations of western philosophy and science, describes natural world and model of cosmos, (cid:862)o(cid:374) the hea(cid:448)e(cid:374)s(cid:863) + (cid:862)meteo(cid:396)olog(cid:455)(cid:863) Aristarchus: thought sun was center for the universe, was able to determine relative earth- moon / earth sun, when the moon half-full, angle of sun moon earth = 900. Ptolemy: saw a(cid:396)istotle(cid:859)s model for cosmos was flawed.