Idiothronos

Definition

A planet sits on its own throne — idiothronos (Greek ἰδιόθρονος, "private-throned") — when it holds at least two of its essential dignities in one place: any two of house, exaltation, triplicity, and bound. Holding a single dignity is not enough; the throne is the reinforced, enthroned state that comes from two or more stacking together.

In Tradition

Hephaistio's Book III preserves Ptolemy's definition from Tetrabiblos I.23: a planet must be in at least two of its dignities to be on its own throne. Hephaistio, perhaps recalling Ptolemy's treatment of phases, adds that a planet rising out of the Sun's rays may also count. The throne surfaces in the illness-electional doctrine. There, the throne-status of the star following the underground pivot decides the physician's origin. A star in its own triplicity or domicile points to a native physician; a star sitting in another planet's territory points to a foreigner.

In Practice

Check a planet against its four essential dignities in the place it occupies. If two or more line up — say it rules the sign and also the bound, or sits in its exaltation and its triplicity — it is on its throne. An enthroned planet reads as settled and well-supported, a ruler at home rather than a guest. One dignity alone does not earn the throne. Use it as a strength signal: an enthroned planet carries its significations with more steadiness and command than a merely dignified one.

Historical Origin

The definition is preserved in Hephaistio of Thebes, Apotelesmatics Book III (Appendix E, Fragment V.41; in Benjamin Dykes' edition, footnote 59 on p. 172, trans. Eduardo Gramaglia), which records Ptolemy's rule from Tetrabiblos I.23 that a planet needs at least two dignities for its throne, with Hephaistio's own phase-extension noted.

Etymology

Origin: Greek. Meaning: in one's own throne; private-throned.

Further Reading

• Hephaistio of Thebes, Apotelesmatics Book III
• Chris Brennan, Hellenistic Astrology