Why I Use Porphyry Houses*
  by Bruce Scofield

*(This article appeared in the Fall/Winter 1992/1993 issue of The Ascendant,  The journal of the Astrological Society of Connecticut)

For many years now I have been one of a handful of Western astrologers who use Porphyry house cusps in client work and in chart examples for books or in classes. Early in the late 60's I used Placidus, but mostly because everyone else did and the tables were readily available. In the early 70's I studied Uranian astrology and was introduced to the Meridian House system. I think it was in 1976 that Rob Hand held Master Class 0 at his house on the Cape. (This Master Class on spherical astronomy predated the Master Class on spherical astronomy, Master Class 1, held in 1980 in Onset.) During that week I was exposed to the wonders of "house cusp mental masturbation," an activity that has fascinated the best minds in astronomy and astrology for ages. Although I could, more or less, follow the arguments for each of nearly a dozen systems, I found it hard to believe that all of these methods could work. So I decided to do an experiment.

First I computed all the intermediate house cusps in my chart in the following systems: Placidus, Koch, Campanus, Regiomontanus, Meridian, Porphyry, and Alcabitius. I eliminated Equal houses because these cusps are really only aspects to the Ascendant. I then tracked the passage over these cusps by slow moving outer planets and progressions. I had decided that if any of these systems was worthwhile, then it should deliver the appropriate kinds of events when the house cusps were contacted. In other words, I decided that for a house system to work, its cusps must be sensitive points that react to transits or progressions and they must "produce" events falling within the appropriate symbolism. A few years later I made my choice and have stayed with it ever since.

Now, before looking at my results, consider that most people use Placidus for the same reason I used to -- everyone else does. How many really understand the abstract time/space equations that go into producing these cusps? Not many, and even worse, the explanation for the system in Dalton's Table of Houses, for decades the main table of houses for every astrologer, is wrong also. So astrologers have been using a system that they can't even understand and have let a faulty explanation go on getting reprinted.

Other house systems are quite complicated also. All sorts of lines are drawn through imaginary points and translated to the ecliptic. I kept thinking to myself, all the action in Western astrology happens on the ecliptic, why do we need to relate all this other stuff to it? After a few days of Master Class 0 it became apparent to me that most house systems were just plain complicated. The simple systems like Equal and Porphyry were barely touched on in the class because they offered no mental challenge. Both of these simply divide the ecliptic up. In Equal, perhaps the oldest house system, the ecliptic is divided into 12ths from the Ascendant. Every cusp is at the same degree in each of the signs. This is a very easy system to use but it doesn't put the Midheaven on the cusp of the 10th house. In some charts it could be in the 11th or 8th houses. Somehow this didn't resonate with my feeling that the Midheaven was too important to be in a house, it is one of the four directions that make up the horoscope. In my view, the first astrology is the four directions and this survives in modern astrology as the angles. They must then be the framework on which the houses hang.

Porphyry is a house system named for the a neo-Platonist of the 3rd Century AD who wrote on Pythagorus, Plotinus and Ptolemy. In his system the arcs between the angles are simply tri-sected. It's all very simple and it's all on the ecliptic and it keeps the Midheaven as the cusp of the tenth house. How basic. But does it work?

After a year or two of observations, I decided that some of the house systems were absolutely worthless and settled in on Placidus, Porphyry, Koch and Meridian. The spread between the cusps generated by these systems was wide enough to catch individual events using an orb of about 7' of arc. I watched the movement of Pluto over the cusp of the third house and recorded what happened. Here's some results.

Placidus: 3rd cusp is 13 Libra 56.
There were five transits to this cusp in a two year period. I was in a hospital for a week, I was busy, I moved into a house, my dog was born and I worked on my car.

Meridian: 3rd cusp is 15 Libra 39.
I changed engines in my VW, I started writing a book, and I took a remarkable backpacking trip in the Adirondacks.

Porphyry: 3rd cusp is 19 Libra 13.
I drove through deep snow to an important banquet. I sold a car. I had serious parking problems for a week, I paddled down the Delaware River in a canoe, and my car engine overheated.

Koch: 3rd cusp is 19 Libra 24.
I worked in a different place for a week, my dog ran away, I took a long hike and then a vacation in the mountains.

When Jupiter crossed over my fifth house cusp I noted the following:

Meridian: 5th cusp is 15 Sagittarius 39.
It took a trip in a limo to a clients office, picked travel times for a client and took photos of my friends who had a singing telegram business at the railroad station.

Porphyry: 5th cusp is 19 Sagittarius 13.
I spoke to the Rotary Club, went to an NCGR education committee meeting, visited my old Sagittarius girlfriend in NYC and took some photos of models.

Placidus: 5th cusp is 22 Sagittarius 14.
I sold a camera, met a Sagittarian at a library to discuss megalithic boulder alignments and played with my band at a party.

Koch: 5th cusp is 26 Sagittarius.
I did a lot of astrology readings, mostly for Sagittarians, saw Return of the Jedi and held auditions for a drummer.

One more sample of my experiment might be worth considering -- Saturn transited my 6th cusp recently.

Meridian: 6th cusp is 13 Capricorn 17.
I got a headache and chipped a tooth, my parents visited me and I had to wake up in the middle of the night to pick up a Capricorn friend coming in on the train.

Porphyry: 6th cusp is 21 Capricorn 35.

I was very busy working and then smashed my car into a concrete barrier after a long, slow side on ice. I ripped out my basement bathroom, and I got sick.

Placidus: 6th cusp is 25 Capricorn 15.
I heard Ram Dass speak, I gave a talk on astrology, I built a set of swings for the backyard and I hurt my knee.

Koch: 6th cusp is 26 Capricorn 30.
I had a relapse from a sickness that had been going on for weeks.

Well, the facts speak for themselves. All of the four systems that made the finals in my study seem to work, though Meridian and Porphyry might be a little more to the point. As I mentioned early in this article, I had been using Meridian since the early 70's and found it great to use on a 90 degree dial, but it doesn't keep the Ascendant as a house cusp and you already know that in my mind, the Midheaven and the Ascendant must be the framework of from houses. (You see, even I have caught the mind disease of house cusp creators -- an obsession with geometry and ideal form.) So it all came down to three. Ultimately, Porphyry won in part because it was much easier to calculate than the other two. When I chose Porphyry, there were no computers, only calculators, so it made good sense to use a house system that could (1) be cranked out fast and (2) definite ly worked, at least as well as a few others. I remember taking the AFA test on a broken calculator and having to do all the calculations three times. If I wasn't using Porphyry I might not have finished. One really great thing about this system is that only two intermediate cusps need be calculated. I just trisect the arc between the Midheaven and Ascendant and add this figure to the Midheaven to get the cusp of the 11th house. I then add this same figure to the 11th cusp to the 12th cusp. Because of the geometry of the circle, the cusps of the 2nd and 3rd are numerical reflections of the 12th and 11th. The numbers are the same, you just have to eyeball the sign that they should be in. No sweat.

I got to liking Porphyry houses. They have always worked for me and I still use them even though I do all my charts by computer. I like the simplicity of an all-ecliptic system. No imaginary lines creating more imaginary lines. One (the ecliptic) is enough for me, thanks. And besides this, Porphyry is the house system of choice among Indian astrologers. I guess I'm really not alone.