Rhys Chatham explains how the major house division systems are calculated in a way that does not require any math.
Rather than advocate the use of one house system over another, we will simply compare them and look at the various celestial circles they are based on, reflecting upon the symbolic implications of each of them and how they might impact on chart interpretation. We’ll discuss what distinguishes one house system from another, allowing you to make informed choices on which ones to use, for what, and when.
In this talk we will cover the ecliptic-based (whole sign, equal and Porphyry), space-based (Meridian, Regiomontanus, Campanus), and time-based houses (Alcabitius, Koch and Placidus).
It’s free! If you would like to attend, click on the site (below) to register and get your ticket and Zoom codes.
House division systems are based on different celestial circles. After a quick review of the astronomy, we’ll discuss those differences and look at how they might affect chart delineation on both symbolic and practical levels.
This article on ecliptic-based house division is Part 3 of a three part series. To start at the beginning , click here.
Porphyry is a quadrant house system. In quadrant house systems, the ascendant defines the first house cusp, and the MC defines the tenth house cusp. This creates four sectors or zones within the circle of the ecliptic, otherwise known as quadrants.
Named after the third century Neo-Platonist philosopher and astrologer, Porphyry, this system was used from the earliest days of horoscopic astrology and was described by Vettius Valens in Book 1 of Anthology, his astrological textbook.
In the Porphyry system, the span of the ecliptic between the horizon and midheaven is trisected to produce three houses. This makes the houses very easy to calculate, you can practically do it in your head! Because the number of degrees between the ascendant and MC vary according to location, time of day and season, the quadrants are rarely of equal size.
The advantage of Porphyry houses is that the first house cusp starts at the degree of the Ascendant, and the degree of the MC defines the 10th house cusp, thus underlining the importance of angularity in horoscopic astrology. In doing this, Porphyry anchors houses to the earth in that it is the local horizon that defines the start of the first house, and the local meridian that defines the 10th house cusp and MC.
One reason astrologers use quadrant house systems is for the same reason that they use the tropical zodiac: because they are tied to what’s going on in the sublunar world. Just as the tropical zodiac is tied to the earth’s seasons, quadrant houses are tied in profound ways to the physical earth itself. The idea behind using quadrant houses is that they better reflect what is happening in the terrestrial world as opposed to the sidereal world.
Furthermore, with Porphyry, we distinguish and underline the difference between a planet being domiciled in a sign and a planet being in an astrological house.
An astrological house represents things that are linked to the Earth that we live on, the domiciles are in the heavens. For example, we could have two planets domiciled in Aquarius, with Mercury in Aquarius in the 12th House and Saturn in Aquarius in the 1st House (see chart below).
We lose this symbolism in Whole Sign houses (see chart above), but we get it back in quadrant systems and in systems where the 1st House starts with the Ascendant, which is one reason why ancient astrologers used quadrant house systems in addition to WSH cusps.
Granted that the Porphyry system is more anchored to the earth and that it is a quadrant system, it is still based primarily on the ecliptic. So, after a time, astrologers began entertaining the idea of basing the houses on celestial circles other than the ecliptic, perhaps ones that were more linked to the earth, such as the celestial equator and/or the prime vertical. This would bring us to a discussion of the space-based houses, which we will save for a future blog. For now, let’s move on to our conclusions of what we’ve covered so far…
We’ve been discussing the ecliptic-based house systems: Whole Sign Houses (WSH), Equal and Quadrant Houses. Which house system should we use?
Which one to use depends on what system of astrological praxis one is following. If you’re following Project Hindsight (Robert Schmidt, Robert Hand) and its followers, you’ll probably want to use mainly WSH, using equal and perhaps quadrant houses for planetary strength and length-of-life. However, later scholars who reviewed the same material as Project Hindsight have recently arrived at alternative interpretations regarding Hellenistic house doctrine. Some seem to think that degree-based quadrant houses were used by the ancients for topics, in addition to planet-strength and length of life. These scholars conclude that the ancients (Dorotheus, Ptolemy, Valens, et. al) used quadrant houses for more precise readings, when the exact birth time was available. Exact birth times often were not easily come by in ancient Greece, in which case WSH were used.
This undoubtedly was most often the case (no exact birth-time) resulting in a highly developed Hellenistic technique of using sign-based aspects and houses for delineating a chart. Also, it made casting a chart less time consuming (no computers in ancient times), so it makes sense that degree-based houses and aspects were used only when a birth time was available and when a high degree of accuracy was called for.
However the ancient Greek astrologers may have calculated their house cusps, my policy with respect to these new scholastic findings is to keep an open mind and not fall into the trap of turning previous interpretations of the ancient Greek authors into dogma. On a practical level, my personal choice is to use both WSH and quadrant houses for topics in the context of natal readings.
Modern astrologers, of course, feel free to pick and choose whatever techniques work for them. If you fall into this category, I would highly recommend basing your choice on the celestial circles that we have been discussing. Keep in mind their symbolism, and use whichever house system corresponds best to the goals of your astrological tradition (ancient, classical, humanistic, psychological, evolutionary, etc.)
As we have seen, each house system is based on a different set of celestial circles, which render varying house cusps and sometimes put planets in different houses. Let’s say that this happens when using whole sign houses and Porphyry on the same natal chart (see example above).
Saturn jumped from the 12th House to the 1st House, oh dear! What do we do?!?! Which chart do we use? Which one is “right”?
The answer to this question is that both charts are right; the only thing that is happening is that we are seeing the same native from different perspectives! It is not a question of choosing between one or the other. Both must be interpreted.
So, when looking at a natal chart, I have found it is always best to try putting it in more than one house system to see if any of the planets change houses. When they do, I look at the changes with interest and delineate both.
Working simultaneously with two house systems often yields interesting information. For example, if I’m using WSH and Porphyry or some other quadrant system, when I see a planet move from one house to another, I interpret both and see what resonates with the client. With clients who are past their second Saturn return, I have found that both usually resonate, representing different aspects or periods of their lives. For younger clients this is not always the case, because it may be that the symbolism represented in one of the charts has simply not happened yet.
Another thing to keep in mind is which house system we use depends on what we are attempting to do.
For example, if we are focused on prediction, we might use one house system, in horary we might favor another, in natal analysis another. Ideally, the house systems we use would be based on which celestial circles are used to determine the house cusps, and how the symbolism of those circles relates to what we’re trying to accomplish. For example, what is prediction? It is a form of fate. Where does fate come from? One way of putting it is that it is in the hands of the universe. It might make sense to use whole signs in that case, since the house cusps in whole signs are based in the heavens, rather than where we live on the planet Earth. On the other hand, if we are looking for a lost object, we might want to use a space-based system like Regiomontanus. We’ll talk about space-based systems in another article.
Moving on, in conclusion, I’d like to say that all the symbolism I’ve mentioned up to now are just ideas to get the conversation going amoung present day astrologers: traditional and modern. Rather than arguing in favor of one house system over another, it might make more sense to focus our research on which house system is best for which astrological technique based on the celestial circles that come into play.
The article is Part 2 of a three-part series on ecliptic-based astrological house division. If you haven’t read Part 1, click here.
Part 2: Ecliptic-based House Division:
The Equal-House system is a variation of the whole sign house system. The difference is that the degree of the ascendant defines the start of the first house and becomes the starting degree of each of the remaining eleven houses. The MC floats and does not define the cusp of the tenth house.
Since Hellenistic times and before, astrologers have been concerned with the motion of the planets rising over the horizon, culminating at the MC, and finally disappearing into the darkness at the descendant. This is called primary motion, it is concerned with the rotation of the earth on its axis and with the motion of the stars, luminaries, and planets above us as they move during the course of the day.
The Acendant is the point where the ecliptic meets the local horizon. With the equal house system, we start to anchor the houses to the rotation of the earth by linking the ecliptic with the local horizon of the native or event. As we have noted in a previous post, the ecliptic is extra lunar, it is not of this earth. However, the local horizon is sublunar. So, with equal houses, ancient astrologers found an initial way to ground the ecliptic to events on earth.
The personal point of the degree of the Ascendant is emphasized in this system. The symbolism becomes a bit more grounded in that the eastern horizon takes on an elevated importance.
In the entire range of traditional natal astrology, the first house represents YOU, it represents the native. The rest of the houses represent everybody and everything else! Echoing the degree of the Ascendant in each of the subsequent houses underlines that this house system symbolizes YOUR money (2nd house), YOUR siblings (3rd house), YOUR home (4th house), and so on.
To compare equal houses with whole sign, in WSH there is no difference between a planet being domiciled in a sign and a planet being in a house. In whole sign houses, we don’t really have houses, what we have are signs. Can signs alone be used to define house cusps? Of course they can! The WSH system was probably used extensively in Hellenistic times and is one of the major approaches in Vedic astrology. However, when we use this method we lose the connection of astrological houses moving clockwise by primary or diurnal motion. In WSH, secondary motion along the ecliptic is emphasized, that is, planets and other objects in space moving in a counterclockwise direction along the ecliptic.
In WSH, signs are houses. A planet domiciled in a sign in WSH exactly corresponds to it being in an astrological house, so we lose the symbolism that we get when we separate domiciliation (Jupiter and Neptune in Pisces) from the symbolism of houses (Jupiter in Pisces in the 1st House, Neptune in Pisces in the 2nd House).
In Equal Houses, we start to get this symbolism back (see chart above). We put the signs back in the heavens, as the first manifestation of the Primum Mobile, and we begin to ground the houses back to the geocentric earth, where, after all, we live!
By defining the Ascendant as the start of the first house, we regain the demarcation between a planet being domiciled in a sign (Jupiter and Neptune in Pisces) and planets being in an astrological house (Jupiter in Pisces in the 1st House, Neptune in Pisces in the 2nd House).
However, the work of the ancient astrologer was by no means finished! The equal house system was still a non-quadrant house system in that the MC is floating. To further ground the houses to the sub-lunar realm of the earth, the ancients developed other house systems, which anchored the local meridian or latitude of the native to the cusp of the culminating tenth house.
In my next post, we’ll look at the quadrant house system that is most often referenced by scholars to the Hellenistic period. Today, it is known as the Porphyry house system.