Published October 4, 2023. Read time: 30 minutes.
This paper evaluates the accuracy of Ibn Ezra’s compound scoring model for identifying the Victor of the Horoscope, a medieval astrological concept derived from the Hellenistic Kurios or Lord of the Nativity. The Victor is understood as the single most important planet in the birth chart—one that reflects the soul’s pre-incarnate choice and life purpose, often expressed in vocation or destiny. The study tests twelve different permutations of Ibn Ezra’s model across a hand-rectified sample of 330 horoscopes, including U.S. presidents, public figures from James Hillman's The Soul’s Code, spree killers, and others.
The model versions combine variations in house system (whole sign vs. Alchabitius), decan system (Chaldean vs. triplicity), and use of triplicity rulers (in-sect vs. all). The results are sobering: none of the twelve versions surpassed a 40% match rate between the model’s calculated Victor and the author’s independently chosen “empirical” Victor based on biographical and predictive techniques (e.g., Firdaria, Zodiacal Releasing, primary directions). Most models scored between 34–38%, a rate only modestly better than chance.
While some permutations slightly outperformed others—such as using in-sect triplicity rulers instead of all three, or whole sign houses over quadrant systems—the differences were small and not statistically significant. The author suggests that biases inherent in essential dignity scoring systems (e.g., unequal bound and triplicity distributions) make it difficult to assume an even 20% probability across the five planetary candidates. A future Monte Carlo simulation could better define the true random odds.
Ultimately, the paper concludes that Ibn Ezra’s scoring model, while popular among traditional astrologers for its apparent objectivity, fails to deliver the reliability expected of a predictive tool. Its poor performance casts doubt on compound Victor systems in general, and the paper echoes Benjamin Dykes’s earlier critique that lumping essential dignity with house strength in compound victor scoring models lacks theoretical justification.