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Pythia was an ancient oracle, believed to have been one of the writers of the Sacred Scrolls, some 3,600 years prior to the events of the Miniseries and the destruction of the Twelve Colonies of Kobol.
Pythia's writings are both obscure and yet well-known: obscure, in that her entire writings are not widely studied among modern Colonials, but well-known in that extracts are widely quoted, often out of context, such as the following:
Key to Pythia's writings are two passages, relating to the exile and rebirth of the human race:
President Laura Roslin, while giving a press briefing 36 days into the flight of the surviving Colonials, had a hallucination that her podium showed two snakes crawling on it, and then a dozen (The Hand of God). Additionally, Pythia wrote that the anointed leader had a "wasting illness" and would not live to enter the new land; Roslin is dying of cancer at the time.
In the second passage, Pythia foretells of an initial battle in which the Colonials are "led by serpents two and ten" and are victorious over their foes. During their flight from the Cylons, the Colonials are forced to attack a Cylon base in order to obtain fuel. The attack is led by twelve Vipers (The Hand of God). However, Pythia's writings on the battle foretell it leading to a larger confrontation, this time "at the home of the Gods." (The Hand of God)
The writings of Pythia appear to have particular interest to the Cylons. Leoben Conoy used quotes from Pythia during his interrogation, and goes on to point out to Kara Thrace that while her people kneel before idols, "You don't realize your destiny has already been written" — another reference to Pythia's foretelling of the exile (Flesh and Bone).
It is unclear, particularly in the context of "all this has happened before" if Pythia is writing history which repeats, or prophecy or both. Her writings are always in the past tense, and some phrases clearly refer to past events (the journey to Earth) while in other instances it is said she has "foretold" events. However, text from the book of Pythia is used to help locate the Tomb of Athena which is alleged to be constructed during the great exodus 1,600 years after her writing. (Home, Part II)
The Pythia was a Sibyl, the Oracle of Delphi. While the temple at Delphi was closely identified with Gaia, the mother of Earth (and responsible for laying the foundations for the Olympian gods), Delphi itself had a close association with Apollo.
The Sibylline Books or Sibyllae were a collection of oracular utterances, set out in Greek hexameters, purchased from a sibylla, meaning prophetess in Greek, by the last king of Rome, Tarquinius Superbus. These books were consulted at momentous crises through the history of Rome and only fragments have survived, the rest being lost or deliberately destroyed.
The Sibylline Books should not be confused with the so-called Sibylline Oracles, twelve books of prophesies thought to be of Judaeo-Christian origin.
Pythia talks of a flood which destroyed most of humanity, and left it rejuvenated (The Hub). A deluge of this nature is present in many mythologies with western audiences likely to be most familiar with the biblical story of Noah's Ark.