Protasis (Omen)

PROT-uh-sis

Definition

The protasis is the "if" clause of a Mesopotamian omen — the part that records what was observed. It could be a celestial event, something on earth, a feature of a person's body, or a detail of ritual; a scribal scholar called an ummanu wrote it down and tied it to a predicted outcome, the apodosis. This two-part "if X, then Y" shape, sometimes called the "cased prediction," is the basic building block of Akkadian and Sumerian omen literature, including the great celestial-omen series Enūma Anu Enlil.

In Tradition

In Babylonian celestial divination, the protasis is the technical name for the observation half of the omen pair. Rochberg, Koch-Westenholz, and Hunger-Pingree all describe the protasis-apodosis structure as the standard form of Mesopotamian prediction. Protases ranged widely: some recorded things genuinely visible in the sky — eclipses, planetary risings — while others were unobservable cases that the compilers worked out on paper, simply to cover every possibility a sign could take.

In Practice

A Mesopotamian scholar used the protasis as an index. Working in one of the official omen series — Enūma Anu Enlil for sky signs, Šumma izbu for unusual births, Šumma ālu for signs on earth, Sa.gig for medical signs — he matched what he had just observed against the recorded "if" clauses, and the matching one led him to its outcome. The mukallimtu commentaries quoted protases alongside their outcomes, sometimes shortened, to add explanation and alternative readings. In the celestial-omen texts, a protasis describes exactly the configuration to look for — a halo around the Moon with a planet inside it, an eclipse of a particular colour and timing, a star rising earlier or later than its schedule. This "if-then" form later shaped the conditional reasoning of Hellenistic astrology.

Historical Origin

The protasis is attested across the second and first millennia BCE in Akkadian and Sumerian cuneiform omen compilations: Enūma Anu Enlil (from Old Babylonian precursors through its Neo-Assyrian canonical edition around 700 BCE), the Sargonid Letters and Reports to the Assyrian Kings (SAA 8, c. 700-650 BCE), Šumma izbu, Šumma ālu, Sa.gig, and the Diviner's Manual. Modern treatments include Rochberg (*The Heavenly Writing*, 2004), Koch-Westenholz (*Mesopotamian Astrology*, 1995), Hunger (SAA 8, 1992), and Hunger & Pingree (*Astral Sciences in Mesopotamia*, 1999).

Further Reading

  • Francesca Rochberg, The Heavenly Writing: Divination, Horoscopy, and Astronomy in Mesopotamian Culture
  • Ulla Koch-Westenholz, Mesopotamian Astrology
  • Hermann Hunger & David Pingree, Astral Sciences in Mesopotamia