Early Greek cosmology refers to beliefs about the structure (cosmography) and origins (cosmogony) of the cosmos (Greek kosmos) primarily from the 8th to 5th centuries BC before it was superseded by ancient Greek astronomy, which was demythologized and involved the systematic study of the world. The main features of early Greek cosmography are shared with those found in ancient near eastern cosmology. The basic elements of the cosmos include (a flat) earth, heaven, the sea, and the netherworld (Tartarus), the first three of which corresponded to the gods Gaia, Ouranos, and Oceanus (or Pontos).[1]
Some primary sources for early Greek cosmology include the poetry of Homer (the Iliad and the Odyssey), Hesiod (the Theogony and the Works and Days), and surviving fragments from Mimnermus.
In the 5th century BC, Greek thinkers began to add new features to this cosmology. One, advocated by figures including Xenophanes, Parmenides, and Empedocles advocated the view that the kosmos as a whole (and not the Earth in particular) was spherical. Empedocles and Anaxagoras advocated for a notion called "vortex", which describes a rotation of the cosmos that explains the visible rotation of the stars.[2] When the spherical model of the Earth was proposed, early Greek cosmology as a whole began to be replaced, although this was not immediate. Geographers like Ctesias and Ephorus rejected a spherical Earth in the 4th century BC. Among authors from the early Roman Empire, Strabo, Tacitus, and the Epicureans continued to accept a flat Earth. The last Greek author known to maintain this position was Cosmas Indicopleustes in the 6th century AD.[3]