The logic behind triplicity rulers
Recently I’ve been thinking about triplicity rulers and wondering about the logic behind the different systems. I first learned triplicity rulers from William Lilly’s Christian Astrology (1647) and later learned the Dorothean system from Dorotheus’ 1st century work Carmen Astrologicum. The two systems have some similarities and some important differences.
As a refresher, here is the Dorothean system of triplicity rulers:
And here is Lilly’s more simplified version which he attributes to Ptolemy:
As you can see, Lilly assigns only two rulers to each triplicity (day and night rulers) whereas Dorotheus assigns three (day, night and participating rulers). Both authors use the classical seven visible planets. It appears that Lilly has greatly simplified the Dorthean system by eliminating the “participating” ruler of the triplicity. In addition, Lilly appears to have eliminated the day and night rulers of the water triplicity and used only the participating triplicity ruler, Mars. In doing so, Lilly almost certainly introduced an erroneous understanding of Ptolemy into the astrology of his time.
Here is a table I put together to illustrate the logic behind the triplicity rulers:
[image error]
William Lilly appears to have selected the domicile ruler of the fixed sign of each triplicity as its principal triplicity ruler by day.
For diurnal Fire (Aries, Leo, Sagittarius), Lilly’s day ruler is the Sun, which rules fixed Leo. This leaves Jupiter as the night ruler. Mars cannot be used because it is of the nocturnal sect and is quite malefic in a day chart.
For nocturnal Earth (Taurus, Virgo, Capricorn), Lilly’s day ruler is Venus because Taurus is a fixed sign. His night ruler is the Moon which is exalted in Taurus and is the leader of the sect.
For diurnal Air (Gemini, Libra, Aquarius), Lilly’s day ruler is Saturn because Aquarius is a fixed sign. Even though Saturn is a malefic, it is a member of the day sect, and its more positive attributes are likely to manifest in a day chart. Lilly’s night ruler is Mercury, which rules Gemini. Venus cannot be used because it is of the nocturnal sect.
For nocturnal Water (Cancer, Scorpio, Pisces), Lilly’s day ruler is Mars because Scorpio is a fixed sign. His night ruler is also Mars, but there is little logic in his position because both Venus and the Moon are available to be used as triplicity rulers of Water.
Dorotheus uses the domicile rulers of the fixed signs as well as the exaltations of the planets in his system of triplicity rulers. The sect of the planets is also of paramount importance.
For diurnal Fire (Aries, Leo, Sagittarius), Dorotheus uses as his day ruler the SUN which is exalted in Aries and also rules the fixed sign Leo. Jupiter becomes the night ruler. Mars cannot be used because it is of the nocturnal sect. Saturn, as the remaining member of the diurnal sect, becomes the participating ruler.
For nocturnal Earth (Taurus, Virgo, Capricorn), Dorotheus uses as his day ruler VENUS which rules the fixed sign Taurus, and as his night ruler the MOON which is exalted in Taurus. Mars, which is exalted in Capricorn, becomes the participating ruler. [It is notable that Mercury rules Virgo and is exalted there, but does not appear as a triplicity ruler of the Earth signs, probably because Mercury’s sect varies according to its position relative to the Sun. Pingree, however, in his translation of the Arabic version of the Carmen Astrologicum does have the phrase, “in Virgo there is also a participation of Mercury,” so it appears that either Dorotheus or his Arabic translators considered the idea of Mercury as a triplicity ruler of the earth signs. At least one modern practitioner of Hellenistic astrology, Rafael Gil Brand, uses Mercury in this way.]
For diurnal Air (Gemini, Libra, Aquarius), Dorotheus uses as his day ruler SATURN, which is both exalted in Libra and ruler of the fixed sign Aquarius. Mercury, as ruler of the air sign Gemini, becomes the night ruler. Jupiter, as the remaining member of the diurnal sect, becomes the participating ruler.
For nocturnal Water (Cancer, Scorpio, Pisces), Dorotheus uses as his day ruler VENUS which is exalted in Pisces, and as his night ruler MARS which rules the fixed sign Scorpio. Mars cannot be a day ruler because it belongs to the nocturnal sect and is quite malefic in a day chart. The Moon, which rules Cancer, becomes the participating ruler because it is neither exalted nor the domicile ruler of a fixed sign in the Water triplicity.
It seems to me that Dorotheus’ system has a tightly reasoned logic, whereas Lilly’s system makes little astrological sense, especially as regards the water triplicity. Why would an astrologer grant primary dignity to Mars as a day ruler of the water signs in a diurnal chart in which Mars is the malefic of the contrary sect and capable of such grand maleficence? Because Scorpio is a member of the water triplicity, Mars has some dignity as a participating triplicity ruler, and this does serve to mitigate its malevolence a bit in a day chart; but Mars remains the malefic of the contrary sect and an extremely problematic planet during daylight hours.
Anthony Louis's Blog
- Anthony Louis's profile
- 29 followers

