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 Astrolabe.com here.
Our example chart the NeoPorphyry and Porphyry systems is the Mexican folk artist, Frida Kahlo.
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.
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.
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.
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.
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.
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.
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.
Based on the data from the New Yorker Magazine article, this is our presumptive guess for President Trump’s mother’s horoscope. The reason that she has so many intercepted houses is because she was born in a very northern latitude and Koch seems to do no better with them than Placidus except that the interceptions move.
Who is Mrs. Trump?
We rectified Mrs. Trump’s chart to 9:12 PM, giving her a 10 Sagittarius ascendant, which E.C. Chambers in his book, Degrees of the Zodiac Analyzed, says is “zeal”.
PM Winston Churchill has the same degree for his Sun. Her Temperament Type is a Bucket with a Jupiter Handle. Typically, Jupiter in the Twelfth House, particularly in its own Lord, would make the native a very religious person, but in Mrs. Trump’s case it is afflicted by Moon in the Third house, and so while she probably attended Sunday services, it was more out of duty than devout belief.
Also, Jupiter handles show up in people who are highly conventional and supportive of established societal values, but in an ostentatious manner and so do everything in a big and grand way (her son seems to have inherited that flair).
We know little about Mrs. Trump herself, other than tidbits reported like the New Yorker story aforementioned. The Map though does shed a little more light on the lady, confirming that she was born with some amount of wanderlust to leave her native Scotland and go aboard, full of optimistic conviction that things would turn out.
With Pluto in her seventh house, we wonder if the reason was not because as her 28 Pluto in Gemini suggests that she felt that the opportunity in her natives Lewes was “bankrupt” and as the keyword for this symbol suggests, she needed “deliverance” from a bleak and sterile environment. If so, going to New York City and not a much closer, London, was a rather fortuitous choice. Maybe the issue there was London was not far enough, or as a Scottish patriot, she did not want to become English.
Neptune and Mars in the Seventh house suggest that while she married a dynamic and energetic man, they were different and so his busy business schedule and her busy societal one worked out well after the initial attraction; Neptune suggests that they had little in common other than their children and the ambitious dreams of a New York “power couple.”
Mrs. Trump has no aspects for her Line of Vitality.The orb between the Sun and the Moon is too great to matter. Marc Edmund Jones writes that in that case, that she does not take physical control of her life, but relies much more on fate, rather à propos for a devout Presbyterian.
The only planetary pair that she has is the Line of Personality, that aspect between her Saturn and Jupiter. In Mrs. Trump’s case it is trine like the Swiss psychologist Carl Jung. This Dr. Jones writes, that she has a “natural momentum” with great sensitivity to her opportunities. It also agrees with her presidential son, that it belies her “surplus of mental energy” in handling anything thrown at her. It would seem that besides her golden hair, President Trump also inherited a few other attributes from his Mum.