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Medieval Predictive Astrology:  The Renaissance

The philosophical worldview taken by Regulus Astrology LLC primarily rests on teachings of the ninth century Arabic Astrologer Abū Ma’shar.   This style of astrology is a blend of Babylonian, Greek, Persian, and Islamic influences which reached its intellectual height during the Islamic Golden Age.  Beginning in the 12th century, a wave of translations helped bring the collected scientific knowledge of Arab Civilization to Western Europe in what many historians now define as the 12th Century Renaissance, a predecessor to the more well-known European Renaissance dating from the 14th to 17th centuries. 

Not unlike prior periods of intellectual renaissance, the modern era has witnessed a revival in older methods of astrology.  Approached from the perspective of the history of science, academics including Otto Neugebauer, E. S. Kennedy, and David Pingree led the first wave of translations in the second half of the 20th century.  Robert Zoller’s translation of Bonatti’s On Arabic Parts in the early 1980s helped open the door to this forgotten field for contemporary astrologers.  In 1993, Project Hindsight organized the first serious stab at translating Arab, Greek, and Hebrew texts for the practicing astrological community.  The co-founders of the project were Robert Schmidt, Robert Zoller, Ellen Black, and Robert Hand.  With a focus on the Hellenistic (Greco-Roman) tradition, the work of Project Hindsight continues today under the guidance of Robert Schmidt.    

The 2007 publication of Bonatti’s complete Book of Astronomy, translated by Zoller student Ben Dykes marked an accelerated unmasking of works from prior eras.  It is expected that within the next ten years the majority of surviving ancient astrological texts will be available in English translation. 

Regulus Astrology LLC:  Research Projects

Since 1980, most of the revival of Medieval Predictive Astrology has concerned itself with history, translation of texts, and transmission/impacts on culture.  As important to understanding the practice of astrology as these topics are, there is no guarantee that these ideas remain relevant and their stated methods actually work.  What is required is systematic testing of the assumptions and models behind Medieval Predictive Astrology.  To this goal Regulus Astrology LLC dedicates its research efforts.

Current Research Focus (updated April 2010)

Recently I have worked on physiognomy, temperament, and manners; all techniques used to construct a natal medical and psychological profile.  Currently I am spending most of my time with astrological physiognomy with the goal of fine tuning models for predicting physical appearance.  Since physiognomy and temperament have the same basis in humoural physiology, getting a better grip on physiognomy opens a backdoor to temperament theory whose models should theoretically use the same set of significators.

Research Findings

Click on + for research publications by topic.  Highlight and click on publication title for website and direct download links. 

Natal Astrology

I. Rectification

+A Rectification Manual: The American Presidency

A Rectification Manual: The American Presidency (December 17, 2007) is designed to provide concrete answers on the mechanics of medieval predictive methods:  how they can be systematically employed, taught, and practiced by contemporary astrologers viewed through the lens of natal chart rectification.  As the book’s introduction makes clear, there is no current consensus on rectification because the modern predictive toolbox is grossly under specified.  A three stage rectification method is proposed which incorporates the full gamut of medieval predictive techniques.  Their application is sequenced such that the robustness of each method is commensurate to the level of uncertainty encountered during each stage of the rectification process.  

Horoscope data files for American Presidents and First Ladies compatible with Solar Fire, Janus, Placidus, and Morinus software programs are available for free download in the member’s area.  Registration required.

II. Delineation


Whether a child will be stillborn, take nourishment, survive infancy, or survive to adulthood was considered the first delineation topic in natal astrology for medieval astrologers.  Chapter 4 “The Arcus Vitae” in A Rectification Manual proposed a model for computing the hīlāj (“root of life”) based on methods of Al-Qabīsī and Bonatti.  A discussion of the al-kadukhadāh (“giver of years”), the killing planet, and the arcus vitae follows.  Appendices C and D includes worked out examples of this methodology for thirty-nine American Presidents and forty-one First Ladies.


Defined as judging character from bodily features by the Greeks in the 4th Century BCE, physiognomy was first developed by a group of medical-philosophers operating outside the scope of astrology.  Beginning with Ptolemy, astrologers split judgments of physical appearance and character into two separate categories.  What is now referred to as astrological physiognomy is limited to physical appearance of the face and body.  For character, see the heading for ‘Manners’ below.

Astrological Physiognomy: History and Sources (April 20, 2010).  A comprehensive literature review of astrological physiognomy from the Greco-Roman period to the present day.  Includes works canonical to the non-astrological physiognomy tradition beginning with the pseudo-Aristotelian Physiognomica (3rd Cent BCE). 71 pages.

Astrological Physiognomy: Empirical Tests of the Leo Rising Decan (April 16, 2010).  A test of methods for predicting the shape of the face based facial models of John Willner (1991) and the rising decan (Hindu decans).  Majority of examples support the Sun’s sign and not the Sun’s season as the contributor to physiognomy.  Study raises questions on inclusion of Sun’s season in temperament models as recommended by Ptolemy. Thirty-six examples.  Horoscopes sourced from Astrodatabank; no rectified charts used.  57 pages.


The four primitive qualities, the four elements, the four humours, and the four temperaments are concepts created by Greek medical-philosophers between the 5th and 3rd centuries BCE.  Labels for the four classical temperaments - sanguine, choleric, melancholic, phlegmatic - were in common use during Medieval and Renaissance periods.  Initially meant to define an individual’s humoural balance for medical applications, descriptors for the classical temperaments were later expanded to include personality and were used to great effect by writers (Chaucer) and playwrights (Shakespeare) for stock character development.  As used by modern 21st century psychologists, the concept of temperament is exclusively oriented to personality.

Temperament and Manners: A Medieval Astrological Profile of Abraham Lincoln (February 16, 2009).  A preliminary paper using temperament models of Greenbaum and Frawley predicted a primary phlegmatic temperament which is at odds with Lincoln’s well-known and documented primary melancholic temperament.  Lincoln’s known depressive episodes are compared with dates computed by directing Saturn (significator of melancholy) to the Ascendant, Moon, and Sun.  24 pages.

I plan on revising this paper after I have concluded additional research on physiognomy.  One missing feature of astrological temperament models appears to be modification of temperament by chronic disease delineated by the 6th – 12th house axis.  For Lincoln, the Venus/Aries – Mars/Libra opposition ruling the 6th – 12th house axis appears consistent with John Sotos’ diagnosis of multiple endocrine neoplasia type 2b (MEN2B), a genetic cancer which most often forms in the thyroid and adrenals glands.  Sotos (The Physical Lincoln, CreateSpace, 2008, ISBN 978-1440420146) correlates MEN2B with Lincoln’s physical features associated with the melancholy temperament.  With Venus ruling the thyroid and Mars ruling the adrenals (and both afflicted in Lincoln’s horoscope), Sotos’ thesis is consistent with a chronic disease of the 6th -12th house axis which fundamentally modified Lincoln’s physical appearance and temperament.  24 pages.


Judgment of manners (or “soul”) differs from temperament by including the Moon and Mercury and their rulers as significators.  Prediction of either good or evil behavior is derived from this delineation exercise.  It is the medieval equivalent to what modern psychologists would label as personality. 

American Spree Killers: Delineating Evil in the Natal Horoscope (in preparation).  Considers four models for evil as a predictor for mass murder:  Moon’s configurations (a/c Maternus), Ruler of the Chart (a/c Ibn Ezra), Manners (rulers of Ascendant, Moon, and Mercury), Fixed Stars (when configured with one or more significators of manners), and Temperament (a/c Ribiero).  First compiled as individual posts in the members area in the summer of 2009, I am currently editing entries to for presentation in a single document. 


Central to the list of significators for wealth is the lot of fortune, the most well-known lot of approximately one hundred.  Lots are computed zodiac positions based three horoscopic inputs.  The lot of fortune (for diurnal figures) is computed by projecting the distance taken from the Sun to the Moon from the Ascendant.  For nocturnal figures, the computation is reversed, e.g., the distance from the Moon to the Sun is projected from the Ascendant.  There exists some ambiguity in the literature for nocturnal figures whether or not the computation should be reversed.  Using data for twenty-two American Presidents, “Appendix B: Tests of Sect Influence: Part of Fortune/Fidaria” in A Rectification Manual confirms the validity of the reversed formula for nocturnal figures. 

Lot Calculator.  An Excel spreadsheet model for computation of all lots is available for download from the member’s bulletin board.  Registration required.

III. Prediction


Fidaria is a time lord technique believed to be of Persian origin created during the Sassinid Empire.  Fidaria entered the Medieval Arabic tradition during the translation wave initiated by the Abbasid Caliphate beginning 750 CE.  What is controversial is an alternate sequence of planetary time lords for nocturnal figures.  Insertion of the North Node and South Node Fidaria period following the major Mars period for nocturnal figures is recommended by Robert Zoller and confirmed by analysis for twenty-two American Presidents.  See “Appendix B: Tests of Sect Influence: Part of Fortune/Fidaria” in A Rectification Manual for details.

+Primary Directions

As practiced by Medieval astrologers, primary directions occupied a central, if not the highest position, within the predictive hierarchy.  Long abandoned for their mathematical complexity in favor of the easier to calculate secondary progressions, primary directions have been revived within the last ten years by traditional astrologers. 

Primary Directions Notation: Towards a Uniform Presentation Standard (April 21, 2010) is an adapted excerpt from the User’s Guide to my second book America is Born.  Suggested is a uniform method for primary directions notation for citations in articles and books.

Primary Direction Sequence.  In using primary directions as one predictive tool for natal chart rectification, I made an important discovery named the ‘Primary Direction Sequence’ which proposes a different solution to treatment of latitude for directing aspects.  The Primary Direction Sequence is explained in both of my books and the following book review of Martin Gansten’s 2009 book on primary directions. 

Directing through the Bounds (a.k.a. “circumambulations”).  A more specialized application of primary directions is named Directing through the Bounds which is a sophisticated Hellenistic time lord technique best described in Abū Ma’shar’s book on solar returns.  My second book America is Born features a comprehensive example of the Directing through the Bounds technique. 

Book Review: Primary Directions: Astrology’s Old Master Technique
by Martin Gansten (October 6, 2009)
.  The bulk of the review debates the limits of primary directions theory.  An unabashed supporter of the Ptolemaic semi-arc proportional method of directing, Gansten disputes many later permutations of primary directions on theoretical grounds.  A case in point is a dispute over directions computed for George Washington presented in A Rectification Manual: The American Presidency.  Submitting Washington’s rectification to another round of empirical tests, I consider a total of twenty-nine primary directions of Jupiter to the angles for the Revolutionary War Era (1768-1783).  66% these directions corresponded with life events which matched the direction’s delineation within 1 week or less; 97% did so within 1 month or less.  In addition to shedding light on the validity of additional permutations of primary directions, this empirical study outlines a six-step approach for delineating the promise of a given primary direction.  Results continue to support the validity of Egyptian bounds and the ability of the Primary Direction Sequence to generate a series of events within a discrete time period based on both zero and full latitude assignment to planets and their aspects. 

Primary Directions: The Practice Manual (201X).  I have committed to writing a book on the technique of primary directions.  Like all of my publications, the style will be empirical and supported by worked out examples of financiers, politicians, and religious figures.  Its publication date is not in the immediate future.

Mundane Astrology

+The Regulus USA National Horoscope

Ever since Ebenezer Sibly first introduced his proposed horoscope for the Declaration of Independence in his 1780 book “The Celestial Science of Astrology”, agreement on the correct USA National Horoscope has proven elusive with over a dozen different horoscope variations proposed.  America is Born:  Introducing the Regulus USA National Horoscope (November 25, 2008) is unique for its application of medieval astrological techniques to the question of modern National Horoscopes.  Included as a special application of primary directions is the largest empirical study of Directing through the Bounds ever attempted or presented.  Results that the directed Ascendant times shifts in the national consciousness represent a significant contribution to the history of American social movements.

Available for download in the member’s area is a complete set of primary directions presented in Excel spreadsheets, annual profections for all significators, Fidaria, and rectification details of the thirty-eight individuals included in Appendex C.  Registration required.

+2008 United States Presidential Election

2008 USA Presidential Election; Birth Chart Rectification: Candidates and Contenders (November 20, 2007).  Provides complete rectifications for Michael Bloomberg, Hillary Clinton, John Edwards, Al Gore, Rudy Giuliani, Mike Huckabee, John McCain, Barack Obama, Mitt Romney, and Fred Thompson. 

The Birth Time of Barack Obama: Out-of-Sample Tests (December 30, 2008).  This article documents procedures for confirming a rectified birth time which may vary from a reported birth time.  In statistics, this procedure is labeled an ‘out-of-sample test.’  Testing continues to support the proposed rectified birth time of 7:54:28 PM despite the official birth certificate time reported as 7:24 PM. 


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