Full and Empty Degrees

Definition

Full and empty degrees are a Hellenistic-medieval degree-doctrine, set out by Firmicus Maternus in Mathesis IV.22. It splits each sign's 30 degrees into two kinds: 'full' degrees, which hold the stars of the 36 decanal star-groups, and 'empty' degrees, where no decan-star falls. A planet or angle in a full degree delivers what it signifies at full strength; one in an empty degree loses force and tends toward weak or unhappy outcomes. Holden traces this idea forward as the source of the later Arabic 'bright' and 'dark' degree lists.

In Tradition

The idea here is that the zodiac is not active in equal measure all the way round — the decan-stars sit on particular degrees, and the rest is treated as inert. Greenbaum reads this as Firmicus's way of explaining how the decan's spirit-charge flows into chart placements, and notes its weight in astrological medicine. The doctrine grades a placement before aspect or dignity is even considered: where a planet sits decides whether it has substance to give.

In Practice

Astrologers use full-and-empty-degrees as a rough high/low filter on placements, at decan-level resolution. You check the degree of each important point — Sun, Moon, Ascendant, dispositors, Lot of Fortune — against a given sign's list of full degrees: planets in full degrees are read as able to do their job, while planets in empty degrees are read as diminished, and Firmicus's cookbook readings shade toward 'unhappy' or 'mediocre' outcomes for them. Greenbaum stresses the doctrine's force in astrological medicine, where Firmicus follows Nechepso's logic of predicting illness from the decans: an empty-degree natal Ascendant or Moon points to a weaker constitution. Holden notes that the same scheme passes into the Arabic tradition as the bright (luminous) and dark (obscure) degrees of Bonatti and Lilly, where the original decan-star reasoning survives as practical degree-categories used in horary and natal judgment. The list of full degrees is specific to each sign and tabulated in Firmicus IV.22; modern editions reprint the table.

Historical Origin

The doctrine comes from Firmicus Maternus, Mathesis IV.22 (4th century CE), where the full and empty degrees of each sign are tabulated outright. Greenbaum, in The Daimon in Hellenistic Astrology (2016), treats it as Firmicus's decan-charge apparatus; Holden, in A History of Horoscopic Astrology (2006), traces its survival into the Arabic 'bright/dark degrees' tradition of Bonatti and Lilly. Bram's 1975 translation and the Project Hindsight Hellenistic editions are the standard modern access points.

Etymology

Origin: Greek-Latin. Meaning: Full (occupied by decan-star) vs empty (unoccupied) zodiacal degrees.

Further Reading

• Firmicus Maternus, Mathesis
• Dorian Gieseler Greenbaum, The Daimon in Hellenistic Astrology
• James H. Holden, A History of Horoscopic Astrology