Neoporphyry House System & Frida Kahlo

The NeoPorphyry house system is a modern update to the older Porphyry.  Walter Pullen of Astrologica Software created it for his software.    Both are based on the quadrant system Ptolemy mentions in the Tetrabiblos, but the real appeal of Porphyry based systems is it easy to calculate without computers. 

Kent McClung of the Hyperion Symbols uses the Porphyry, as does Bruce Scofield.  The latter gives his reasons in this article on here.

 Our example chart  the NeoPorphyry and Porphyry systems is the Mexican folk artist, Frida Kahlo.



Major Notes:

  • Both  Porphyry systems have intercepted houses.
  • House  sizes are unequal.
  • The Midheaven is tied to the 10th house.
  • The Ascendant is tied to the first.

The original Porphyry

The major differences are the cusp calculations but even the aspects are the same.

The NeoPorphyry

Walter Pullen does not mention his rationale for the Neo’s creation, or perhaps we are not familiar enough with his documentation to find it.  Mr Scofield in his above cited essay, do not mention it.

                            The NeoPorphyry vs. Placidus


Frida Kahlo’s NeoPorphyry house format

A better comparison is the NeoPorphyry to the popular Placidus format.   We have the two here easier visual viewing.  The differences though are not remarkable: Jupiter now falls in the Neo’s 8th house, while in the Placidean it is the 9th of education and philosophical/religious beliefs.

Frida Kahlo’s Placidus house format                 Prior to computers almost all the table of houses and ephemerides were Placidean based, so to compare Frida Kahlo’s chart we use that.  The 20th century Koch house system updates the Placidean to alleviate some problems with higher latitudes, not applicable here with Frida’s Mexican birth,  and so the table of houses for Frida do not differ.  Morinus the house system we prefer,  puts both Jupiter and the North Node in the eighth house and leaves Mercury alone in the ninth. 





Campanus House System.

The mathematical brothers Johannes and Matthias Campanus,  born around 1250 AD, created this house method but it did not become popular until about 150 years after their death when Regiomontanus said his system was an improvement to theirs. 

What the Campani brothers do is divide the sky into twelve houses using the Prime Vertical instead of the celestial equator, a similar idea to our terrestrial equator . 

In both cases,  a great virtual circle intersects the celestial sphere and both hemispheres are equidistant from it.  The difference is in the terrestrial equator these equidistant poles are horizontal, while in the celestial side both halves are vertical.  This causes the equinox.

The table of houses, instead of recording the entire path of the line between houses, gives just the boundary of each house as a single positional line bounding a house across the Ecliptic.  As planets move along  Ecliptic,  unequal houses and interceptions occur.

French-American Dane Rudhyar made this house system popular using for archetypal psychological work; Australian astrologer Bernadette Brady, current president of the AFA,  uses it too for the same reasons.

Major Notes

  • The Ascendant is the first house cusp.
  • The Midheaven  or the Medium Coeli is the tenth house cusp.
  • The Campanus system allows interceptions. 
  • Houses are unequal & can vary from 15 to 32 degrees wide.

Regiomontanus & Bogey

For this comparison  we are using our good friend, the late Mike “Bogey” Boguslawski, best known for his Hartford Connecticut television show “On your side.”  

Neither system gives Mike any interceptions.  The cuspal house boundaries are different making in the Regiomontanus the Part of Fortune in the eighth, while with Campanus with the Arabian part is the seventh tying his career opportunities to other people: notably his sister Rita (in the fifth house for both).  Other than that, the charts are very similar.

His obit is here.

The Campanus House System and Bogey

The major differences between the two charts are:

  • The Part of Fortune in the Regiomontanus is in the 8th House (death & endings) while in the Campanus it is in the 7th (opportunities from others).
  • Mercury moves from the Regiomontanus’s 5th house (creative  to the Campanus’s 6th house (work & service).


Modern update:  Bogey and Koch

With the modern Koch method, Bogey’s chart changes more than one would think.  The Part of Fortune is now in work and service square religion and higher calling, showing the problem he had with higher radio executives who wanted him to change to a more marketable focus. 

Pluto in the eleventh highlights his investigative work as a consumer advocate, similar to fellow Nutmeger Ralph Nader.Bogey though worked on a local scale, even when he moved to L.A.

The Placidus House System

This is the most popular house system in astrology and it was formerly called the Ptolemaic House System, though it is doubtful that Ptolemy who wrote in 3 AD used it.  The “Ptolemaic” name was because Placidus de Titis,  an Italian Monk & mathematician, made this after carefully reading and re-reading the Tetrabiblos while marking up the then popular Regiomontanus system.  His changes were a break from his predecessors — he changed the emphasis from a space-oriented system to a time based emphasizing the how long it took for the ascendant to reach the meridian.

Part of its early success was that it kept popular features of the prior system — like the tenth house is always the Midheaven and it ties the ascendant to the first house, interceptions and unequal houses — while arguing for chart stability.  This latter facet is also the Placidean’s greatest fault — in northern latitudes, like London, some houses can span 40 degrees while others to offset that  shrink to eight.   The argument against that issue is the shrinkage is happening in empty houses.   Nonetheless, despite its handicaps  it was used by London astrologers and their publications because it was the first “modern” house system and not French (see Morinus).

In America, its popularity grew because of Dalton’s Table of Houses while overseas in Britain, all of their 19th Century astrologers, Alan Leo,  Sepharial, Charubel, the Golden Dawn &  Aleister Crowley are among its fans.  As Leo had a very popular magazine and put out his 1001 Nativities using it for reference, the Placidus format continued its stronghold into the 20th Century with Elbert Benjamine and the Church of Light, Marc Edmund Jones and his Sabian Assembly and Vivian Robson using that manual for their published works.

We take our example chart from the AFA archives.  Harold was born in Baltimore, Maryland, but if we move his birthplace to different locations around the world always using the Placidus format, we can see the different mappings of his chart.  This may not be problematic for everyone, but it is amusing.

Meridian House System

There is little information on the Meridian House System. Australian astrologer, David Cope, who worked under the magical name of Zariel, created it in the early 1900s in an attempt to fix the older Morinus method — he changed the emphasis from the ecliptic to the meridians. It does have many similarities to the older method  but the major difference is that its cusps are on the meridians and not equatorial.   

This effect will be noticed if you have have a lot of “cusp” planets, and from our observations, the planet now goes to the previous house. 

Alfred Witte and the Hamburg school used the Meridian system before abandoning the house system entirely and going to his 90 Degree Uranian Dial.   Other fans were Astrometeorologist Carl Payne Tobey & Sydney Omarr  were also fans.



Major Notes:


  • The Meridian like the Morinus aims to minimise intercepted houses and keep the houses as close to 30 degrees as possible.
  • Cusps are based on the Meridians which lend a certain amount of stability to the chart because of their North-South axis, so  interceptions are few though they will still appear in extreme northern latitudes.
  • This University of Illinois site explains the phenomena well. 
  • The Midheaven is not tied to the 10th house.
  • The Ascendant is not tied to the 1st house.

Meridian example

Writer cum explorer Jack London’s natal chart in Meridian (Zariel in Janus 5) format.

Our example chart here is writer adventurer Jack London.  Neither chart links the ascendant to the first house cusp, a notable feature of the predecessor formats.  Pluto in the Meridian is in the 12th house; while in the Morinus it is in the first.

Typically in both systems, the houses are 28-32 degrees wide something that rarely happens in the Placidean where they can shrink as far as 8 degrees wide to as large as 40 but that was their aim — house stability.

Morinus example

Writer-explorer Jack London’s chart in Morinus format.

As the cuspal houses are calculated along different lines, they differ.   This is noticeable  in the London chart above with Uranus at 19 Leo 00 in the 3rd house in the Meridian, and safely 5 degrees away from the cusp,  but in Morinus is right on the cusp.  

Another noticeable difference is in the Meridian London’s Saturn is 24 Aquarius 22 and in the tenth house; in the Morinus, while located at the same degree , now  conjunct the Midheaven in the ninth house.

And since we are discussing Midheavens, in the Meridian, London’s Venus is one degree away from the Midheaven. 22 Aquarius 33.

Equal House System

The Equal House house is often confused with the whole House system, both are astrology’s oldest division of the zodiac The Ecliptic, the imaginary sphere  that encircles the celestial spere, and some astrologers call it the Ecliptic system.  The difference between the Whole and Equal systems is the equal house starts all houses with the ascendant’s degree; the whole resets this to zero.

Download Havelock-Ellis here.

Dr. Ellis was an English essayist and physician who studied human sexual behavior.  He challenged 19th-century Victorian taboos against public discussion of the subject very similar to the much later American Masters & Johnson studies. 

Many of his books, including his best, The Task of Social Hygiene, can be found here on; we have used some of his case studies for this project.

Major Notes


  1. All the houses are equally spaced —  each house is exactly thirty degrees wide, so it very easy to  construct manually.
  2. All the houses start with the degree of the ascendant, so any degree before is in the previous house.
  3. There are not any  intercepted houses, as each sign gets its own house, i.e. the map has twelve equal parts.
  4. As the ascendant is the start of each house, the tenth house cusp does not coincide with the Midheaven.
  5. The late Lois Rodden loved the Equal house.

Equal House

I have drawn an arrow to show the tenth house which is now Scorpio and semi-sextile his Venus in the eleventh.  This aspect ties his public health studies closely to his sex studies, also his most well-known work.  

The twelfth house shows the luminaries in a close conjunction, highlighting how he worked on a taboo topic like sex with great fascination (opposition to Saturn).



In the Placidus format, Venus is in the tenth house of dreams and aspirations and the twelfth house the same.  The interceptions in the first and seventh house hint that his motives may not be as pure and scientific as he stated, adding some titillation to the observations.

The Equal fourth house planets of Jupiter and Uranus are now in the third house emphasizing his writings on previously socially unaccepted topics.

The Whole House System

Despite Havelock Ellis’s ascendant being late, the whole house differs greatly from the Equal because it rests it to be the prior zero, thus all the houses are off by one.