Astrology House Systems - Placidus, Porphyry, Campanus, Koch and many more - Which One To Use?

by Robert Wilkinson

I've been receiving a lot of mail about the different house systems and how they affect our charts, since which one we use can shift our planets from one house to another. This is important as it involves how we trisect the quadrants of our chart. I wrote this a while ago when I was told some people were flipping out over which system to use. Enjoy, since it's still very relevant and may help resolve any conundrum you may have about this rather obscure, but very important, subject.

This is my original post:

"House Systems - They're all in your point of view"

Well, imagine my surprise to find an email in one of my accounts saying that over at a well-known astrology chat room an entire comment stream had been bombed due to excessively abusive discourse. Wow.

Here's what I was mailed, with the name of the site deleted:

To all members, Within the context of intellectual exploration and learning, debate is an essential element. (This site) encourages productive discourse. When a post or thread sinks to the level of caustic and inimical personal confrontation all focus and value is lost, (this site) and its members denigrated. The “What House system do you use?” thread fell into that category. The thread has been deleted, all good content along with the counterproductive. Verbal abuse of life’s demigods and demons, according to your perspective, is acceptable. Abuse within the ___ community is unacceptable.

As I said, wow. I've seen people get heated about various things, but never about which house system an astrologer uses. Can't figure out how it happened, don't really want to jump in over there, and it seems that this uncivil discourse mirrors the general state of affairs in our world today.

So of course, it leads me to try to explain what some of this business of different house systems is about. Basically, only the horizon (ascendant-descendant) and meridian (midheaven-nadir) are fixed by what time one is born, and where. How you derive the boundaries (cusps) between houses is entirely based on whether you calculate on the basis of a space-based system, a time-based system, or a space-time based system.

Placidus houses are space-time, Equal houses are space-based, as is Porphyry. There are others, such as Campanus, Koch, Regiomontanus, Morinus, Alcabitian, Albategnian, and even those that divide the sphere into 8 sectors instead of 12 as well as those that eliminate all the houses. An extensive article on the merits and demerits of each of these would probably bore most of my readers, so we won't go there.

Though there is no consensus on which system is the best (and it seems that some fans of certain systems are ready to come to blows with each other!), I have always used several systems simultaneously in my work with satisfactory results. I found when I first started studying astrology that some of my planets change houses depending on which system is in use.

For example, I have Saturn in the 3rd house using the Placidus system, whereas it's in the 2nd using Porphyry and Equal. So which is it? Well, reading the texts, I realized it seemed as though both were correct. That led me to the conclusion that since none of these house "boundaries" are set in stone, perhaps I should regard the wheel in terms of zones of overlapping house boundaries, those being the areas where the affairs of the first house and the second house interact, or the second and third, or where the affairs of the 8th and 9th houses overlap, and so on.

Over the years this has worked very satisfactorily for everyone, and helps to explain how to resolve certain dilemmas in how different areas of our charts and lives affect each other. In my case, with Saturn in the overlapping zone between the second and third houses, it would seem that I need to use my Saturn function to understand how it affects the areas of values (2nd) and perception (3rd), and where these meet within me. At times I must deal with a natural Saturn in the 2nd influence; at other times, Saturn in the 3rd. At all times, how these areas meet and interact with each other as expressed through my Saturn filter.

I learn about Saturn from both areas of my life, and find Saturn's influence in both areas, regardless of which house system is in use. You will also find this true in your own charts. When you have a planet that bridges two houses, it is very important in your evolution to link those areas of your life through the planet involved.

Perhaps it would serve astrology (and bring some peace back to the realm!) if we could get over the idea that one system is right and the rest are wrong, since I believe that to be delusional thinking based in linear, exclusionary rationalizations. "Winner-take-all" arguments are the foundation of religious wars by whatever name you call them. I would certainly not want any of my readers to come to blows or insults over something as ridiculous as whether one house system is superior to the rest.

Perhaps this is the biggest advantage to the quadrant system, or the "no house" system. We do not need frets on a guitar neck to hit a note accurately. They are just guide points helping give a reference between points A and B. It's the same with the lines dividing the houses. Anything nearer the horizontal axis is more in the realm of self-not self. Anything near the vertical axis is more in the realm of private-public, or subjective-objective experience.

The relative position of a planet to the meridians is what's important, not whether a planet is "more truly" in one house or another when it's on the cusp. And the idea of insulting someone because they don't agree with a house system is absurd.

(Originally published 12 April 2005)

Comments

[TonI]

Wow, awesome article. Very enlightening. Thank you!

[Don]

Robert-
I played the cello for a while. In the beginning I used three temporary stips of tape on the neck. After a few years I played without the tape. The confidence I built up with practice eventually gave rise to pure enjoyment. This is also true for when I play the classical guitar (no frets), usually I'll practice a song over and over on my acoustic (with frets).

Playing the music is beautiful either way- and I enjoy many different guitars ie classical, accoustic, electric, and I love to occasionally practice on a 3,000 dollar fender at the music store (and I never pretend that I'm going to buy it, I simply ask the music store guy to play the clear-as-bells beauty).

I thought this real life experience my be analogous to the article. I'm not sure where "what fits where" but I see, in one instance, the way I learned cello as similar to my experience with learning astrology thus far.

My Natal Chart reads Geocentric/Tropical/Porphyry/True Node. Now my progressed moon at 26 leo in the seventh. Upon my luner return, my moon returns and refines itself at 0 Virgo in the eigth. I know what the 7th represents and I know what the 8th represents at this stage- if I had learned by equal house or "no house" perhaps my understanding would be different.

The way I see it? My moon in Leo- understanding my personal talents and creative inclinations. My moon in Virgo- recieving an instrument. From 7th to 8th house- learning, practicing, and playing through my Virgo stellium. Now my metaphor may "still just not be quite right" but, that is the beauty of this place, I get to learn and practice with people that are learning and practicing as well!

So for people to argue about what system works the best- I just assume say "wow" too, but wait so what are we wowing about? lol.

See ya guys,
Don.

[Tim]

Wow, that's interesting there would be such a heated discussion about house systems--Mercury must have been square Mars when that thread started...

I've always slightly preferred the Koch system, and I guess that's because the first chart someone calculated for me some twenty years ago used the Koch. Over the years I have come to see how the Placidus system also makes sense, though I stil prefer the Koch. In my case there is an exact Mars-Pluto conjunction (exact to 14 arc minutes) at the last degree of Leo. In Koch this falls at the very end of the 5th house and in Placidus at the beginning of the 6th. This has always been something of a puzzle for me and thus I was eager to read your comments. You said that Placidus is space-time based. Could you explain what the Koch system is based upon? Thanks.

[Don]

Hey all-

Hey Tim what is an "arc minute" time measure that is part of the Koch system? Or is that like a...an aftermarket enhancement, so to speak? I see geocentric as the basic V8, it is what I began learning with.

Well guys "out of the blue" I'm moving into my "third house" this week, making it my second big move and third living space in nine months.

Call me an "oddball" but I have fun moving. At these times I feel like I'm more "in my element." I love the opportunity that comes out of difficulty. The difficulty of having know idea where I am going to go, do, live, gives rise to some of life's most amazing experiences. I like not knowing, since I vibrate to the not knowing, right Robert?

I'm going to miss you guys for a week or two but I will return to these front pages when I have landed. Wish me luck!

Robert, my friends and life-traveling companions, have my blessings and happy holidays!

Wha-whooo....!
Don.

[Robert]

Hi Toni - You're most welcome. Thanks for coming by.

Hi Don - We'd all like clear dividing lines between the compartments of our lives, but keep finding out we need to be able to slide through the notes rather than keep them all stiffly divided. And some notes are so closely related to others that it's the perfect analogy for astrology houses. The sectors still have the meaning they have, just like the length of a string and the equivalent note. But as we get further from one axis and approach another, we move from one life area to another.

Hi Tim - Something was square something, that's for sure! Koch is a "time based system." I prefer "ecliptic based systems," with my main system Porphyry, said to be the second oldest system in use behind Equal House.

Hi Don - "arc minutes" is how far the horizon moves in a minute. You're confusing House systems with Geocentric versus Heliocentric ways of calculating planetary positions. Best of luck landing wherever you need to! And of course to all please have the most Happy Holidays any of us could experience!

[Christine]

Hi Robert,

I was born with Pluto transiting my 2nd house, but when reading about my early years it seems that Pluto could have been transiting the 3rd. So I find the above very interesting.

I'm also intrigued by this:

"Anything nearer the horizontal axis is more in the realm of self-not self. Anything near the vertical axis is more in the realm of private-public, or subjective-objective experience."

I'm aware of the influences from the upper or lower part of the chart... but can each influence go either way? - the self-not self, for example. When I read my chart, I'm often struck by how I really needed certain influences at the time... but I'm not sure I really exalted in them.

[Robert]

Hi Christine - Well, I don't think "the self" can conceive of itself without a "non-self" to confirm it. Sort of like the "I-Thou." Asc exteriorizes through Dsc, and vise-versa. MC and IC hold the same relationship, as do all signs. Leo exteriorizes through Aquarius, and Aquarius exteriorizes through Leo. With Pluto where it is, purify your thoughts about things. See what aggregates motivate your perceptions.

[Karen M]

Thanks for this, Robert! Ironically, deciding on a house system may be one of the major factors that has kept me from doing more serious work with astrology. I know, it sounds silly... but in groups I have attended, and in talking to other astrologers, it always seemed one had to make such a commitment. As far as I could tell, though, everyone seemed to adopt what they had first been taught, and that didn't make sense, either.

When I heard Robert Blaschke talk about why he began using Porphyry most of the time (pre-computers)-- because he could do the calculations without tables of houses, e.., if he was traveling, it made a lot of sense. So, mostly that's what I use, except I still use a computer.

After reading your post, though, I can imagine someone doing interpretations that concentrate on those planets, degrees, etc. that fall in the overlapping spaces.

So, maybe there could be a system called "Overlapping Houses" for those INFPs among us who are just too "P" to choose? ;~)

[Robert]

Hi Karen - I fell into using Porphyry for the same reasons. When I (and we all!) were computing charts by hand, using the STAR method, I could quickly compute the MC and Asc. From there trisecting the quadrants was quick and easy, and I'd note the approximate degree of the Placidus system and impose the Equal house degrees. That gave me a working zone of overlap that allowed me quickly to see what was up. (As an aside, I don't know how anyone could calculate an Asc or MC without a TOH). I had a traveling Raphael's I used to use. Yes, I believe overlapping houses may have more of an influence than most astrologers are willing to grant. And also, yes, of course I would think that, Aries that I am!

[Mike]

Hey all- A 'no man's land' at the cusps, with 3 to 4 degrees on each side, where planets may slip into past conditioning (previous house), or are in the process of setting the stage for a new cycle in the next house. I see it much like a lunation cycle, except each house represents a cycle within itself.

[Robert]

Hi Mike - Yes, in the "in-betweens" we can as easily slip into past as future modes. And you're right, in that each house is a cycle in itself, as well as a phase in a larger reality.

[Jon]

Hi,im fairly new to all this and i picked up my chart, done in porphyry by Jonathan Cainer it is bang on to say the least. so i did my own with a Russel Grant kit. comparing it was similar but the houses on the Porphyry where different sizes, can someone explain this please, Cheers

Jon

[Robert]

Hi Jon - Welcome to the site. I also use Porphyry house division system. There are at least a dozen or so house division systems. Each house system computes the space in the quadrants differently. Unless you were born at the equator, your houses will be of unequal length depending on whether you use a time division system, a space division system, or a space-time division system of houses.

[Jacques]

Hi Robert,

Would you comment on impact of or/and using of various house systems if sun (helio)-centered is used?

Thanks,

[Robert]

Hi Jacques - Well, I don't use that system, so I have no direct experience in how it might be different. I've always believed that since we are Earth created, Earth bound physical beings, that I should use Geocentric charts. None of us actually live on the Sun! ;-) I would think that house systems, being how we measure the zodiac from what we see on Earth, would be similar in how they manifest. They're all systems based on division of the zodiac by space, time, or space-time. This shouldn't manifest differently if we are Sun centered rather than Earth centered. And of course, the Earth in our birthchart is opposite the Sun. Sun in Virgo yields Earth in Pisces, Sun in Aries yields Earth in Libra and so forth.

[Jacques]

Hi Robert,

Thanks. I have seen several mentions about trading commodities futures dealing with helio-centered system data but can't make sense out of them.

I guess that with two view points, we can see the depth of something more from single view point, which can only identify that it is. More like human eye-sight, maybe?

From what I gathered, Helio-centered view doesn't use moon since earth and moon always are together and all the retrograding motions of the planets don't exist, either. Maybe all the House systems disappear, too.

I am just starting to read about it and hope to find some usefulness out of it.

Back on Earth/Geo now ;-)

Thanks,

[Robert]

Hi Jacques - There are many systems and many who tout them, just like handicapping a horse race. I wouldn't think house systems would disappear, since they are a convenience to divide space so we can know which phase things are at relative to the perceiver's point of view. They are the fields once called "constellations" beyond the Solar system. RX is a function of perception relative to a larger whole, in this case our closed Solar system, so it's normal that these would no longer be factors if seen from a Solar perspective. But division of perceptual space into sectors of behavior and involvement? A requirement if we are to measure anything at all. A bass player may not need frets to play the bass, but they do need a neck or there will be no notes to play.

[Jacques]

Hi Robert,

Yes. They won't go away soon and anyone is entitled to have his/her own liking (free will) on the selection of House systems.

Yes, there are no house systems on the helio-centered view, nor mercury, nor moon, and neither even sun itself. I don't think it matters too much as far as spiritual pursuit is concerned when a grand cross appeared in Oct 1987.

Sometimes we find understandings or more clues under a different light - be it Infrared, UV, or something else.

"Truth is sometimes stranger than a Fiction." Unrelated things are somehow connected for no reason at all.

[Robin]

Thank you very much for your very helpful article.:)