In Greek mythology, Chaos (Greek: Χάος), according to Hesiod, Chaos ("Chasm") was the first thing to exist: "at first Chaos came to be" (or was) "but next" (possibly out of Chaos) came Gaia, Tartarus, and Eros (elsewhere the son of Aphrodite). Unambiguously born "from Chaos" were Erebus (Darkness) and Nyx (Night).
The Greek word "chaos" (χάος), a neuter noun, means "yawning" or "gap", but what, if anything, was located on either side of this chasm is unclear. For Hesiod, Chaos, like Tartarus, though personified enough to have born 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.
For the Roman poet Ovid, Chaos was an unformed mass, where all the elements were jumbled up together in a "shapeless heap".
According to Hyginus: "From Mist (Caligine) came Chaos. From Chaos and Mist, came Night (Nox), Day (Dies), Darkness (Erebus), and Ether (Aether)." An Orphic tradition apparently had Chaos as the son of Chronus and Ananke.
- Hesiod, Theogony 116–122.
- West, p. 192 line 116 Χάος, "best translated Chasm"; Most, p. 13, translates Χάος as "Chasm", and notes: (n. 7): "Usually translated as 'Chaos'; but that suggests to us, misleadingly, a jumble of disordered matter, whereas Hesiod's term indicates instead a gap or opening".
- Gantz, p. 3, says "the Greek will allow both".
- According to Gantz, p. 4: "With regard to all three of these figures—Gaia, Tartaros, and Eros—we should note that Hesiod does not say they arose from (as opposed to after) Chaos, although this is often assumed." For example, Morford, p. 57, makes these three descendants of Chaos saying they came "presumably out of Chaos, just as Hesiod actually states that 'from Chaos' came Erebus and dark Night". Tripp, p. 159, says simply that Gaia, Tartarus and Eros came "out of Chaos, or together with it". Caldwell, p. 33 n. 116–122, however interprets Hesiod as saying that Chaos, Gaia, Tartarus, and Eros all "are spontaneously generated without source or cause". Later writers commonly make Eros the son of Aphrodite and Ares, though several other parentages are also given, Gantz, pp. 4–5.
- Gantz, p. 4; Hesiod, Theogony 123.
- Gantz, p. 3; West, pp. 192–193 line 116 Χάος. West, p. 193 notes that 'although grammatically neuter, Chaos is treated as female". As discussed by both West and Gantz, some have argued that Chaos represented the gap between heaven and earth.
- Hesiod, Theogony 814: "And beyond, away from all the gods, live the Titans, beyond gloomy Chaos".
- Hesiod, Theogony 700.
- Ovid, Metamorphoses 1.5 ff..
- Hyginus, Fabulae Preface 1, translated by Smith and Trzaskoma, p. 95. According to Bremmer, p. 5, who translates Caligine as "Darkness": "Hyginus ... started his Fabulae with a strange hodgepodge of Greek and Roman cosmogonies and early genealogies. It begins as follows: Ex Caligine Chaos. Ex Chao et Caligine Nox Dies Erebus Aether (Praefatio 1). His genealogy looks like a derivation from Hesiod, but it starts with the un-Hesiodic and un-Roman Caligo, ‘Darkness’. Darkness probably did occur in a cosmogonic poem of Alcman, but it seems only fair to say that it was not prominent in Greek cosmogonies."
- Ogden, pp. 36–37.
- Aristophanes, Birds 693–699; Morford, pp 57–58. Caldwell, p. 2, describes this avian theogony as "comedic parody".
- Aristophanes, Birds in The Complete Greek Drama, vol. 2. Eugene O'Neill, Jr. New York. Random House. 1938. Online version at the Perseus Digital Library.
- Bremmer, Jan N. (2008). Greek Religion and Culture, the Bible and the Ancient Near East. Jerusalem Studies in Religion and Culture. Brill. ISBN 9789004164734. LCCN 2008005742.
- Caldwell, Richard, Hesiod's Theogony, Focus Publishing/R. Pullins Company (June 1, 1987). ISBN 978-0-941051-00-2.
- Gantz, Timothy, Early Greek Myth: A Guide to Literary and Artistic Sources, Johns Hopkins University Press, 1996, Two volumes: ISBN 978-0-8018-5360-9 (Vol. 1), ISBN 978-0-8018-5362-3 (Vol. 2).
- Hesiod, Theogony, in The Homeric Hymns and Homerica with an English Translation by Hugh G. Evelyn-White, Cambridge, MA.,Harvard University Press; London, William Heinemann Ltd. 1914.
- Morford, Mark P. O., Robert J. Lenardon, Classical Mythology, Eighth Edition, Oxford University Press, 2007. ISBN 978-0-19-530805-1.
- Most, G. W., Hesiod: Theogony, Works and Days, Testimonia, Loeb Classical Library, No. 57, Cambridge, MA, 2006 ISBN 978-0-674-99622-9. Online version at Harvard University Press.
- Ogden, Daniel, Dragons, Serpents, and Slayers in the Classical and early Christian Worlds: A sourcebook, Oxford University Press. ISBN 978-0-19-992509-4.
- Ovid, Metamorphoses, Brookes More. Boston. Cornhill Publishing Co. 1922. Online version at the Perseus Digital Library.
- Smith, Scott R., Stephen M. Trzaskoma, Apollodorus' Library and Hyginus' Fabulae: Two Handbooks of Greek Mythology, Hackett Publishing Company, Inc. Indianapolis/Cambridge 2007. ISBN 978-0-87220-821-6.
- Smith, William; Dictionary of Greek and Roman Biography and Mythology, London (1873). "Chaos"
- Tripp, Edward, Crowell's Handbook of Classical Mythology, Ty Crowell Co; First edition (June 1970). ISBN 069022608X
- West, M. L. (1966), Hesiod: Theogony, Oxford University Press. ISBN 0-19-814169-6.