common Signes

latin: signa communia · greek: δίσωμα (disōma, 'two-bodied'); bicorporeal

Definition

'Common signs' (Latin signa communia) is the medieval terminology — used by Bonatti, Lilly, and the older traditional English literature — for what modern astrology calls the mutable signs: Gemini, Virgo, Sagittarius, and Pisces. The label captures Bonatti's seasonal-disposition reasoning: when the Sun enters one of these signs, the air's quality 'partakes of both' the preceding and following seasons rather than fixing in one mode. Hand's editor footnote in the Project Hindsight edition explicitly records that 'common is the modern mutable.'

In Tradition

In Hellenistic, Arabic, and traditional Western practice the common signs occupy the third position in the threefold modal classification (moveable / fixed / common, or cardinal / fixed / mutable in modern terms). Bonatti's rationale rests on the seasonal-transition pattern: moveable signs initiate a season, fixed signs sustain it, and common signs straddle the change from one season to the next.

In Practice

In horary work the common signs traditionally indicate multiple parties, mixed outcomes, indirect routes, or medium timeframes — Lilly assigns them medium-distance places and 'watery places with rushes and ditches.' A querent's significator in a common sign is read as fluctuating, ambivalent, or open to renegotiation. In natal practice the common-sign tally feeds the modal balance reading: heavy common-sign emphasis suggests an adaptive, plural temperament that thrives on transition. The doctrine also informs Bonatti's per-house relative-time-of-effect judgments — common signs giving mixed-tempo effects between the quick moveable and the enduring fixed.

Historical Origin

Bonatti's Liber Astronomiae Tractate II Ch. XII (early 13th c.) uses signa communia as a fixed-vs-mobile-vs-common technical triad transmitted from Hellenistic and Arabic sources. The Project Hindsight translation by Robert Zoller preserves the medieval Latin terminology and notes the modern equivalence. Lilly carries 'common signs' into early modern English in Christian Astrology Vol 2. The Hellenistic Greek term is bicorporeal (disōma, 'two-bodied'), attested in Ptolemy's Tetrabiblos I.11.

Etymology

Origin: Latin. Meaning: From communia ('shared, common'), referring to signs that share or partake of two seasons rather than fixing in one..

Further Reading