Chaos. Chaos refers to the void state preceding the creation of the universe or cosmos in the Greek creation myths, or to the initial gap created by the original separation of heaven and earth. Greek means emptiness, vast void, chasm, abyss, from the verb, gape, be wide open, etc., from Proto-Indo-European, cognate to Old English geanian, to gape, whence English yawn. It may also mean space, the expanse of air, the nether abyss or infinite darkness. Pherecydes of Syros interprets chaos as water, like something formless which can be differentiated. Hesiod and the Pre-Socratics use the Greek term in the context of cosmogony. Hesiod's Chaos has been interpreted as eitherthe gaping void above the Earth created when Earth and Sky are separated from their primordial unity or the gaping space below the Earth on which Earth rests. In Hesiod's Theogony, Chaos was the first thing to exist: at first Chaos came to be but next came Gaia, Tartarus and Eros. Unambiguously born from Chaos were Erebus and Nyx. For Hesiod, Chaos, like Tartarus, though personified enough to have borne children, was also a place, far away, underground and gloomy, beyond which lived the Titans. And, like the earth, the ocean, and the upper air, it was also capable of being affected by Zeus' thunderbolts. Passages in Hesiod's Theogony suggest that Chaos was located below Earth but above Tartarus. Primal Chaos was sometimes said to be the true foundation of reality, particularly by philosophers such as Heraclitus. The notion of the temporal infinity was familiar to the Greek mind from remote antiquity in the religious conception of immortality. This idea of the divine as an origin influenced the first Greek philosophers. The main object of the first efforts to explain the world remained the description of its growth, from a beginning. They believed that the world arose out from a primal unity, and that this substance was the permanent base of all its being. Anaximander claims that the origin is apeiron, a divine and perpetual substance less definite than the common elements. Everything is generated from apeiron, and must return there according to necessity. A conception of the nature of the world was that the earth below its surface stretches down indefinitely and has its roots on or above Tartarus, the lower part of the underworld. In a phrase of Xenophanes, The upper limit of the earth borders on air, near our feet. The lower limit reaches down to the apeiron. The sources and limits of the earth, the sea, the sky, Tartarus, and all things are located in a great windy-gap, which seems to be infinite, and is a later specification of chaos. In Aristophanes's comedy Birds, first there was Chaos, Night, Erebus, and Tartarus, from Night came Eros, and from Eros and Chaos came the race of birds. At the beginning there was only Chaos, Night, dark Erebus, and deep Tartarus. Earth, the air and heaven had no existence. Firstly, blackwinged Night laid a germless egg in the bosom of the infinite deeps of Erebus, and from this, after the revolution of long ages, sprang the graceful Eros with his glittering golden wings, swift as the whirlwinds of the tempest. He mated in deep Tartarus with dark Chaos, winged like himself, and thus hatched forth our race, which was the first to see the light. That of the Immortals did not exist until Eros had brought together all the ingredients of the world, and from their marriage Heaven, Ocean, Earth and the imperishable race of blessed gods sprang into being. Thus our origin is very much older than that of the dwellers in Olympus. We are the offspring of Eros; there are a thousand proofs to show it. We have wings and we lend assistance to lovers. How many handsome youths, who had sworn to remain insensible, have opened their thighs because of our power and have yielded themselves to their lovers when almost at the end of their youth, being led away by the gift of a quail, a waterfowl, a goose, or a cock. For Ovid, in his Metamorphoses, Chaos was an unformed mass, where all the elements were jumbled up together in a shapeless heap. Ante mare et terras et quod tegit omnia caelum unus erat toto naturae vultus in orbe, quem dixere chaos: rudis indigestaque moles nec quicquam nisi pondus iners congestaque eodem non bene iunctarum discordia semina rerum. Before the ocean and the earth appeared, before the skies had overspread them all, the face of Nature in a vast expanse was naught but Chaos uniformly waste.