Since the first Egyptian farmers discovered the annual reappearance of Sirius just before dawn a few days before the yearly rising of the Nile, ancient civilizations around the Mediterranean have sought to explain the movements of the heavens as a sort of calendar to help guide them conduct earthly activities. Counting phases of the moon or observing the annual variations of day length could, after many years' collection of observations, serve as vital indicators for planting and harvesting times, safe or stormy season for sailing, or time to bring the flocks from winter to summer pastures. With our millennia of such observation behind us, we sometimes forget that seeing and recording anything less obvious than the rough position of sun or nightly change of moon phase requires inventing both accurate observation tools (a stone circle, a gnomon used to indicate the sun's shadow, a means to measure the position of stars in the sky) and a system of recording that could be understood by others. The ancient Greeks struggled with these problems too, using both native technology and inquiry, and drawing upon the large body of observations and theories gradually gleaned from their older neighbors across the sea, Egypt and Babylonia. Gradually moving from a system of gods and divine powers ordering the world to a system of elements, mathematics, and physical laws, the Greeks slowly adapted old ideas to fit into a less supernatural, hyper-rational universe. As ancient peoples began to realize that sun, moon and stars follow certain rhythms in step with the seasons, they began to hypothesize that some conscious set of rules must be dictating these movements and seasonal changes that, for agrarian or pastoral societies, were a matter of life or starvation. So, to explain the natural phenomena a complicated system of gods' interactions with men was born.There are hints of the Greek conception of the universe in Homer, who mentions many subjects ...
