The intersection of medieval scholarship and modern astrological practice reveals a continuous thread of inquiry into the relationship between celestial bodies and human destiny. While the terminology and methodologies have evolved from the scholastic Latin of the 14th century to the digital predictions of the 21st century, the fundamental premise remains consistent: the heavens hold the keys to understanding earthly events. This exploration traces the lineage of astrological thought from the medical encyclopedias of Gerard de Solo to the monthly horoscopes of modern practitioners like Gerard Lenting. By examining historical manuscripts and contemporary forecasts, one can observe how the discipline has shifted from a medical necessity to a tool for personal guidance and life prediction.
The Medical Foundations of Medieval Astrology
In the Middle Ages, the boundary between medicine and astrology was non-existent. Medical texts were inextricably linked to astronomical calculations, a practice rooted in the belief that the position of celestial bodies directly influenced human health and fate. The manuscript Hs. 688, held within the special collections of the University of Utrecht, serves as a primary example of this synthesis. This manuscript contains not only medical excerpts and Salernitan tables but also detailed astronomical tables and horoscopes.
The text "Super Libro IX Almansoris" by Gerard de Solo (died 1360) represents a pinnacle of this medical-astronomical fusion. Gerard de Solo was a physician and lecturer at the University of Montpellier, an institution that held the title of the oldest medical faculty in the world still in operation. His work, completed around 1350, is a Latin commentary on "Al-Hawi Al-Kabir" (The Comprehensive Book), a massive medical encyclopedia by the Persian physician and philosopher Rasis (Rhazes, 854–925). The manuscript was likely copied by Symon Hoflant in 1346 in Montpellier. Given that Symon was in close proximity to the original author, it is highly probable that he copied the work directly from Gerard de Solo. This proximity suggests a direct transmission of knowledge, preserving the integrity of the original medical and astrological theories.
The integration of astrology into medicine was not merely symbolic; it was a practical tool. In the medieval context, an astrologer was often more critical during the birth of prominent individuals than a doctor or a priest. The precise time of birth was recorded to construct a natal chart, which would then dictate medical treatment, dietary plans, and surgical timing. The manuscript Hs. 688 contains astronomical tables specifically calculated for the years 1426 and 1448–1459, providing a chronological marker for the creation of the document.
Within the manuscript, astrological circles appear on folios 1r and 134v. These diagrams were functional instruments used to calculate the "aspectus" of planets. An aspectus refers to the angular relationship between planets, which could consist of three, four, or six signs. The circle on folio 1r depicts aspects of three and six, while the circle on folio 134r includes aspects of four. These calculations were essential for determining the influence of planets on the human body, a practice that permeated the medical texts found on folios 143v onwards, where horoscopes were listed for each zodiacal sign.
The Mechanics of the Zodiac and Planetary Aspects
The construction of a horoscope begins with the determination of the exact time and place of birth. The term "horoscope" itself is derived from the Greek words hora (hour) and skopeo (to see), literally meaning "to see the hour." The process involves mapping the sky at the precise moment of birth to determine the position of the celestial bodies relative to the zodiac.
Traditionally, the celestial sphere is divided into twelve equal parts, each named after an animal, forming the zodiac or "Dierenriem." The nine known planets traverse these signs. Historically, only six planets were recognized until the discoveries of Uranus in 1781, Neptune in 1846, and Pluto in 1930. These discoveries forced a complete recalibration of all previously established astrological calculations. A natal horoscope identifies the zodiac sign under which an individual was born and maps the mutual positions of the planets within that sign.
The concept of "aspectus" is central to this system. An aspect is the geometric angle between two planets as seen from the center of the Earth. In the medieval manuscripts, the aspectus could consist of specific angular relationships, often described by the number of zodiacal signs separating the planets. For instance, a trine aspect involves a separation of four signs (120 degrees), a square aspect involves three signs (90 degrees), and a sextile involves two signs (60 degrees). The manuscript circles mentioned earlier illustrate these relationships, showing how ancient scholars visualized the harmony or tension between celestial bodies.
In modern practice, the methodology remains similar but has been expanded. The zodiac remains the foundation, divided into the twelve signs: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius, and Pisces. Each sign is further divided into three decanates, adding layers of interpretation. The birth time determines the "ascendant" or rising sign, which indicates the physical body and the individual's outward personality.
The influence of planets is categorized by their nature: - Benefic planets (Jupiter, Venus) generally bring favorable outcomes. - Malefic planets (Mars, Saturn) are associated with challenges or restrictions. - The Sun and Moon hold special significance as the primary sources of light and life force.
In the medieval period, these calculations were not just for personal fortune-telling but were integral to medical diagnosis. The position of the Moon was considered critical for the timing of bleeding, surgery, and the administration of herbs. The manuscript Hs. 688 reflects this deep integration, showing how the "medical astrology" of the Middle Ages treated the stars as diagnostic tools.
Modern Interpretation: The Monthly Forecast
While the medieval scholars focused on the birth chart as a static map of life, modern astrology has evolved to include dynamic, time-based predictions. This shift is evident in the "Weegschaal" (Libra) monthly forecasts. A specific example is the prediction for the month of April 2026, which covers the period from Wednesday, April 1, to Thursday, April 30, 2026.
The target audience for these forecasts includes individuals born under the sign of Libra, which spans from September 24 to October 23. The forecast for April 2026 is characterized as a "very positive month." This type of prediction relies on the transits of planets over the fixed zodiacal signs. As planets move through the zodiac, their angles relative to an individual's birth chart create specific periods of opportunity or challenge.
The modern application of astrology has expanded beyond personal horoscopes to include other areas of life. For instance, in England, it has become customary to draw up horoscopes for racehorses based on their birth data to calculate their chances against competitors. This reflects a broader cultural acceptance of astrology as a tool for decision-making and prediction.
The individual named Gerardus Martinus Arnoldus Lenting, born on May 29, 1944, in The Hague, Netherlands, represents the modern practitioner. Born under the sign of Gemini, Lenting has dedicated his work to the study of paranormal events and divination. His methodology includes the use of the "Chevalier" cards and the "Marie-Anne Adelaine LeNormand" oracle cards to gain insight into diverse events. He refers to his work as "The Book of Life" and offers monthly predictions, such as the Libra forecast mentioned above.
Lenting's approach combines traditional astrological principles with cartomancy (card reading). He describes being driven by various visions to specialize in paranormal phenomena. His website serves as a hub for these services, offering daily and monthly predictions. The "Weegschaal" (Libra) section on his site specifically targets those born between September 24 and October 23, providing a tailored outlook for the coming month.
Historical Lineage and the Transmission of Knowledge
The connection between the medieval scholar Gerard de Solo and the modern practitioner Gerard Lenting illustrates the enduring nature of astrological inquiry. While separated by centuries, both figures represent the pursuit of understanding the relationship between the cosmos and human experience.
Gerard de Solo's work, "Super Libro IX Almansoris," was a commentary on Rhazes' medical encyclopedia. This text was copied by Symon Hoflant in 1346 in Montpellier. The proximity of the scribe to the original author suggests a direct transmission of knowledge. The University of Montpellier, where Gerard de Solo lectured, was the center of medical science in the Middle Ages. This institution's legacy as the oldest medical faculty still in operation underscores the authority of the medical-astrological tradition.
The manuscript Hs. 688 contains not only medical texts but also astronomical tables and horoscopes for every zodiac sign. These tables, calculated for specific years (1426 and 1448–1459), indicate the time of creation and the specific astronomical context of the manuscript. The presence of astrological circles on folios 1r and 134v demonstrates the technical sophistication of medieval astrologers. These circles were used to calculate planetary aspects, which were considered vital for medical treatments.
In contrast, the modern practice of Gerard Lenting focuses on personal guidance and prediction. Born in 1944 under the sign of Gemini, Lenting utilizes a combination of astrological forecasting and cartomancy. His "Book of Life" and the "Weegschaal" (Libra) forecasts represent a continuation of the desire to predict the future, albeit in a different cultural context. While medieval astrology was deeply embedded in medicine, modern astrology has become more focused on personal well-being and life planning.
The transition from the medieval to the modern era is marked by a shift in focus. In the Middle Ages, the astrologer was essential for determining the health outcomes of prominent individuals. Today, the focus has shifted to monthly forecasts for the general public, such as the prediction that April 2026 will be a "very positive month" for Librans. This shift reflects the changing role of astrology in society, moving from a medical imperative to a tool for personal empowerment.
Methodological Comparisons: Medieval vs. Modern Practice
The evolution of astrological practice can be clearly seen when comparing the methodologies of the medieval period with those of the modern era. The table below highlights the key differences and similarities between the two approaches.
| Feature | Medieval Practice (Gerard de Solo) | Modern Practice (Gerard Lenting) |
|---|---|---|
| Primary Context | Medical diagnosis and treatment timing | Personal guidance and monthly forecasting |
| Key Text | Super Libro IX Almansoris (Commentary on Rhazes) | Het Boek des Levens (The Book of Life) |
| Tools Used | Astrological circles (fol. 1r, 134v), Salernitan tables | Tarot-like cards (Chevalier, LeNormand) |
| Focus of Prediction | Health, surgery timing, birth charts | Monthly horoscopes, general life events |
| Data Source | Manuscript Hs. 688 (copied 1346) | Birth data (May 29, 1944) and digital platforms |
| Zodiacal Scope | 12 signs, focus on planetary aspects (3, 4, 6 signs) | 12 signs, specific monthly forecasts (e.g., Libra) |
| Institutional Base | University of Montpellier | Independent practitioner (Lenting) |
The medieval approach was rigorous and mathematically precise, relying on complex calculations of planetary aspects. The manuscript Hs. 688 shows that the astrological circles contained specific aspect calculations, such as the "aspectus van drie en zes" (aspects of three and six signs). This precision was necessary for the medical applications of the time. The text Super Libro IX Almansoris was a commentary on a medical encyclopedia, indicating that astrology was a subset of medical science.
In contrast, the modern approach, as exemplified by Gerard Lenting, incorporates additional divination tools. Lenting's use of "Chevalier" and "Marie-Anne Adelaine LeNormand" cards suggests a broadening of the astrological toolkit. His predictions, such as the "very positive month" for Librans in April 2026, are accessible and aimed at a general audience seeking guidance rather than medical intervention.
The Cultural Impact of Astrology
The persistence of astrology from the 14th century to the present day speaks to its deep cultural resonance. In the Middle Ages, the astrologer was a figure of immense importance, often consulted before a doctor or priest for the births of prominent figures. The exact time of birth was recorded meticulously to generate a horoscope that would guide medical decisions.
This tradition of "medical astrology" is evident in the manuscript Hs. 688, which contains astronomical tables calculated for specific years. The presence of these tables indicates a sophisticated understanding of celestial mechanics and their perceived influence on human affairs. The University of Montpellier, where Gerard de Solo taught, was the epicenter of this knowledge, preserving and transmitting these complex theories.
In the modern era, astrology has transformed into a form of personal guidance. The "Weegschaal" (Libra) forecast for April 2026 is a prime example of this shift. It offers a specific prediction for individuals born under that sign, suggesting a positive outlook for the month. This type of content is now widely available through digital platforms, making astrology accessible to a broad audience.
Gerard Lenting's work illustrates the contemporary landscape. Born under the sign of Gemini, he combines astrological forecasting with cartomancy to provide insights into "paranormale gebeurtenissen" (paranormal events). His "Book of Life" and the "Gerard's Vraagbaak" (Gerard's Question Desk) serve as resources for those seeking answers. The integration of these practices reflects a modern interpretation of the ancient belief that the stars hold the key to understanding life's trajectory.
The evolution of astrology also reflects changes in how society views the cosmos. The discovery of new planets (Uranus, Neptune, Pluto) in the 18th, 19th, and 20th centuries necessitated a complete overhaul of astrological calculations. This historical fact underscores the dynamic nature of the discipline, which adapts to new astronomical discoveries while maintaining its core principles.
Conclusion
The journey from the medieval manuscripts of Gerard de Solo to the digital forecasts of Gerard Lenting demonstrates the enduring nature of astrological inquiry. The manuscript Hs. 688, with its medical texts and astronomical tables, showcases the rigorous, mathematical foundation of medieval astrology. The work of Gerard de Solo, centered at the University of Montpellier, established a tradition where the stars were integral to medical science.
In the modern era, this tradition has evolved. While the core mechanics of the zodiac and planetary aspects remain, the application has shifted from medical necessity to personal guidance. The "Weegschaal" (Libra) forecast for April 2026, predicting a "very positive month," exemplifies the contemporary use of astrology. Gerard Lenting, a modern practitioner born under the sign of Gemini, integrates traditional astrological methods with cartomancy to offer insights into life events.
The continuity between these two eras lies in the fundamental belief that the celestial sphere influences human affairs. Whether through the precise calculations of 14th-century scholars or the monthly horoscopes of 21st-century practitioners, astrology remains a tool for navigating the complexities of life. The transition from the medical focus of the Middle Ages to the personal guidance of the present day reflects the changing needs of society, yet the underlying quest to understand the connection between the heavens and the earth remains unbroken.
The historical record, preserved in manuscripts like Hs. 688, and the modern practices found on digital platforms together paint a complete picture of a discipline that has survived and adapted over centuries. From the medical tables of Montpellier to the monthly predictions for Librans, the story of astrology is one of enduring curiosity about the relationship between the cosmos and human destiny.