Manilius and the Three Opinions on Sign Sect
In this installment of this series, I want to just briefly touch on an indication that there was diversity in opinion regarding the classifications of signs into diurnal or day signs and nocturnal or night signs, also known as the classification of the signs by sect. Interestingly, Marcus Manilius, one of the earliest astrologers of the tradition who composed his Astronomica in the 1st Century CE, noted (in Book II, lines 203-222) a diversity of opinion regarding the sect of the signs and he himself favored a sect classification that is no longer used by traditional astrologers.
Fail not to perceive and from true rule deduce what signs are nocturnal, and what diurnal: they are not those that perform their function in darkness or daylight (the name would apply to all alike, since at regular intervals they shine at every house, and now the nocturnal ones accompany the day, and now the nocturnal ones accompany the night), but those one which nature, mighty parent of the universe, bestowed sacred portions of time in a permanent location. The signs of the Archer and the fierce Lion, he who looks round on the golden fleece of his back [Aries], then the Fishes and the Crab and the Scorpion of stinging lash, signs either adjacent or spaced at equal intervals, are all under like estate termed diurnal. The others, identical in number and in the pattern of their spacing, for they are inserted into as many places, are called nocturnal [i.e. there is six of them opposite the six diurnal signs and with the same pattern]. Some have also asserted that the diurnal stations [signs] belong to the six consecutive stars [signs] which begin with the Ram and that the six from the Balance [Libra] count as nocturnal. There are those that fancy that the masculine signs are diurnal and that the feminine class rejoices in the safe cover of darkness. (Goold trans., 1977, p. 99-101; bracketed notes added by me)
We find that by the first century CE, already there were three different means of classifying the signs as diurnal or nocturnal, and Manilius appeared to favor the one that didn’t survive at all. His favored classification is by triplicity, with two triplicities as diurnal (those we associate with Fire and Water, though Manilius does not associate elements with triplicities), and the other two as nocturnal (those we associate Earth and Air). The pattern for this scheme which Manilius favors is two adjacent diurnal signs, then two adjacent nocturnal signs, and so forth; an alternation in pairs, from a Pisces-Aries diurnal pair, to a Taurus-Gemini nocturnal pair, and so on.
Sex of the Signs
The sect classification of the signs that came to dominate in Hellenistic astrology and through later strands of the tradition, is that which Manilius mentioned last, in which the masculine signs are diurnal and the feminine signs are nocturnal. All ancient astrologers appear to agree that the masculine and feminine signs alternate through the zodiac; Aries masculine, Taurus feminine, Gemini masculine, and so forth. A convenient way to remember which signs are masculine and which are feminine, is to know that the Fire and Air triplicities are masculine, as fire and air have a propensity to stir and rise, while the Water and Earth triplicities are feminine, as water and earth have a propensity to fall and settle.
It is most common for ancient astrologers to simply conflate sect and sex. However, this does create some odd conflicts. For instance, it was considered beneficial for a planet to be in a sign of the same sex or sect as itself, but Mars being a masculine planet of the nocturnal sect would not have one of its domicile of both its same sex and sect as the other planets do. However, in the sect arrangement favored by Manilius, the same situation holds for Mars, as both Aries and Scorpio become diurnal signs, but Mars is a nocturnal planet (Corrected 11/21/2011: previously the sentence said that Mars was in sect and sex in Aries, which is not the case, as Aries is diurnal in this arrangement).
Still, I favor the third sect arrangement given by Manilius, in which sect and sex are conflated. Perhaps Mars is so agitated all the time because he simply cannot achieve full comfort in either of his houses. My own approach to astrology is not strongly influenced by Manilius, being more influenced by other Hellenistic astrologers and the Persians. Manilius put a particular emphasis on the signs and actual fixed stars and constellations in his methods, making extensive use of extra-zodiacal constellations, parans, and so forth. Stargazing traditionalists may want to explore his methods in more depth, as there is much material not found elsewhere.
Northern and Southern Signs
The second classification which Manilius gives has the signs from Aries through Virgo as diurnal and those from Libra through Pisces as nocturnal. This is logical from the perspective of the tropical zodiac in the northern hemisphere as Aries begins with the Spring Equinox, a moment where the quantity of day increases over the quantity of night, while Libra begins with the Autumnal Equinox, a moment where the quantity of night increases over the quantity of day. In other words, in this classification, the Sun is in diurnal signs when the length of the day exceeds that of the night, while the opposite is true when the Sun is in nocturnal signs (at least in the northern hemisphere, with the opposite holding in the southern hemisphere).
In Persian medieval astrology this classification is noted, but is referred to as the classification of the signs as Northern or Southern (c.f. al-Qabisi, Dykes trans., 2010, p. 59). This is because the passing of the Sun into Aries, is also the point when the Sun passes north of the equator of the Earth (i.e. the north pole is inclined toward the Sun), while when the Sun passes into Libra, the Sun goes south of the equator (i.e. the north pole is incline away from the Sun). Some may not realize that this apparent passing of the Sun north and south of the equator, due to the tilt of the poles relative to the Sun, is what creates the seasons, not an orbital closeness to the Sun. The Earth is actually closest to the Sun (i.e. at perihelion) around January of each year, during winter in the northern hemisphere.
In conclusion, there were 3 methods of classifying the sect of a sign, and while the method favored by Manilius has all but disappeared, the common method of conflating sign and sex was at least present in some of the earliest strains of the tradition.