Terms (Bounds)

Definition

The terms — also called bounds — are five uneven segments inside each zodiac sign, each one handed to one of the five non-luminary planets (Mercury, Venus, Mars, Jupiter, Saturn). Their widths add up to 30 degrees per sign, but the split varies from sign to sign. Two main tables were in use: the Egyptian terms (also called Dorothean) and the Ptolemaic terms. The Egyptian table was the standard across the Hellenistic world; Ptolemy put forward his own table, saying he based it on an unnamed manuscript.

In Tradition

In the Babylonian-Hellenistic transmission, the terms work as a fine-grained layer of essential dignity — a planet's baseline strength in a sign. A planet that falls in the bound of one of the five non-luminary planets takes that planet as a sub-ruler. The Egyptian terms appear as canonical in Vettius Valens, Dorotheus, and the *Liber Hermetis* tradition. In *Tetrabiblos* I, Ptolemy argues for a different table he credits to an old manuscript — but the Egyptian table stayed more common across the Greco-Roman and medieval Latin worlds.

In Practice

When you assess a planet's essential dignity, the bound-ruler is the third level — after domicile (sign rulership) and exaltation, and before triplicity in some authors. You note the planet's bound-ruler and weigh whether that bound-lord is friendly to it. In horary, a planet in its own bound has a witness of its own and can act on its own behalf even without any higher dignity. In primary directions and time-lord techniques — zodiacal releasing, profections — the bound-ruler can serve as the time-lord of a sub-period; Valens uses bound-rulership for fine-grained timing inside longer stretches.

Historical Origin

The Egyptian (Dorothean) terms are attested in Dorotheus of Sidon's *Carmen Astrologicum* I (1st c. CE), Vettius Valens' *Anthologiae* I (c. 145-175 CE), and the *Liber Hermetis* (a 4th-c. Latin redaction; Zoller's 2002 translation, Ch. XXIII, Egyptian Terms). Ptolemy presents his alternative in *Tetrabiblos* I.21. The Egyptian table passes through the Arabic transmission (Abu Mashar) into medieval Latin (Bonatti) and survives in Lilly's *Christian Astrology* (1647).

Further Reading

  • Claudius Ptolemy, Tetrabiblos
  • Dorotheus of Sidon, Carmen Astrologicum
  • Robert Zoller, The Liber Hermetis Translation