The Zodiac Man and Celestial Regulations of Medical Practice in the Early Modern Period

EPOCH
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Georgia Wallace | Royal College of Surgeons

In the fifteenth and sixteenth centuries, the heavens were regarded as the arbiter of human health. The movements of the planets and the positions of the zodiac signs were believed to exert a direct influence on the soul, the inner body, and even the physical appearance of humans from birth and throughout their lives. It was therefore critically important that medical practitioners understood the impact of celestial movements on the human body to diagnose, prognosticate, and treat physical ailments. The relationship between the zodiac and the body was essential medico-astrological knowledge for physicians and lay people alike, and so the zodiac man – a diagram that visualised the connections between zodiac signs and the human body – was born. The zodiac man was contemporarily considered a model of precise science, and while a wide portion of society would recognise the figure from printed almanacs, it was primarily utilised by medical practitioners.

In the centre of a page is a woodcut print of a man, standing up straight with his arms to his side, showing his palms to the viewer. He is illustrated on a plain, empty background. His face shows a tired expression, and his naked body is covered with illustrations of the twelve zodiac signs. The zodiac signs of creatures are depicted as animals, with human-like expressions, and the others are human personifications. They climb up the man’s figure and interact with him, rather than being superimposed. — Zodiac man from an almanac published by Hans Schönsperger the Elder, 1484, page 26v. (Credit: the Met Museum).

Before examining the zodiac man in detail, it is important to contextualise the illustrations within the larger worldview of the sixteenth century. As a result of the antiquarian revival and Latin translations of Arabic texts, namely Abu Ma'shar al-Balkhi’s Kitāb al-madkhal al-kabīr (The Great Introduction to the Science of Astrology, c. 800), the Hippocratic theological concept of the microcosm-macrocosm became a popular method of structuring (understanding) the order of the universe.

In the centre of the cosmos is the human – forming a ‘little world’, a microcosm, constituted of the mind, body, and soul. The mind was governed by God and functioned independently to the body and the soul. The soul was somewhat of an autonomous and immortal substance, and whilst it transcended the corporeal body, it could be affected by the body. As determined by classical scholar Galen, the body was constituted by the ‘four humours’: blood (sanguine), yellow bile, black bile, and phlegm. The humours were free-flowing bodily fluids that circulated in the blood, with blood being the ‘carrier fluid’ of the other humours. Each had their own qualities - hot, cold, dry, and wet - temperaments, and were directly controlled by the positions of the zodiac, moon, and sun.

Perfect health could be achieved when the four humours were balanced, however this was a near impossible challenge. Everybody had a natural imbalance as predetermined by their natal chart – for example, those born when the sun was in Capricorn would always have a disproportion of black bile – and if this wasn’t hard enough to regulate through one’s life, the humours could also be altered by a myriad of other factors, from diet to the weather.

A printed illustration of a naked man, with legs and arms spread, in the center of 24 thin spheres on a background of dark clouds. The first eleven spheres are titled ‘Microcosmus’, and each has either the name of a humour, planetary, or zodiac symbol inside. The rest of the spheres are titled ‘Macrocosmus’ and again have each zodiac symbol inside. The last sphere has stars evenly placed around it. — A representation of the microcosm-macrocosm from Robert Fludd, *Utriusque cosmi maioris scilicet et minoris metaphysica*, 1621. Credit: The Royal College of Surgeons of England. (Credit: Author’s Image).

If humans were the microcosm, then everything else, from the Earth to God, was the

macrocosm. The structure of the macrocosm surrounded humans in concentric spheres, like Russian nesting dolls. From the centre moving outwards, the number of spheres was: one for the moon, seven for the planets that had been discovered up to this point, one for all the stars, nine for each order of the angels, and lastly the Empyrean, where God and the most blessed souls reside. These spheres were in constant motion, and different conjunctions of the planetary and celestial spheres could cause major problems for humankind, ranging from the aforementioned humoral imbalances to global disasters, such as widespread plague or ecological catastrophes.

The structure of the microcosm-macrocosm, the constant movements of the celestial sky, and how they influenced both the individual and society was a complex system. Whilst the layperson in the sixteenth century may have understood the basics of astrology, it wasn’t until the vernacularisation of medico-astrological knowledge in print later in the early modern period that more people, especially those who did not attend university, could understand astrological prognostication and apply it to healthcare. The zodiac man was a key component in this, as it allowed a wider section of society, ranging from non-university-trained medical practitioners to the non-literate, the opportunity to understand and apply astrological medical theory.

[left] In the centre of a page is a woodcut print of a naked, anatomised man, standing up straight with his arm out, standing on a grassy landscape. Either side of him are six square boxes, each with illustrations representing a zodiac sign. The zodiac signs of creatures are depicted as animals, such as the ram, crab, and lion, and the others are human personifications. Each sign is labelled to the corresponding body part with a thin black line.

[right] In the centre of a page is a woodcut print of a naked man, standing up straight with his arms to his side, showing his palms to the viewer. He stands on a rocky landscape. Across his body are illustrations of the twelve zodiac signs, beginning with Aries on the head and Pisces on the feet. The zodiac signs of creatures are depicted as animals, such as the ram, crab, and lion, and the others are human personifications. Next to each zodiac is a short description of the sign. — Left: Zodiac man from an almanac published by Johann Prüss, c.1483, page 20v. (Credit: Universitätsbibliothek Gießen in the Public Domain). Right: Zodiac man from Johannes de Ketham, Fasciculus Medicinae, 1495. (Credit: The Royal College of Surgeons of England (author's own image) under CC-BY).

Let’s then look at how people ‘read’ the zodiac man, and how the information it provided was put into practice. Johann Prüss’s diagram, above on the left, has the figure anatomised and relies on purely illustrative, ordered representations of the zodiac signs, and labels them against their corresponding body parts. Published a decade later and stylistically different from Prüss, Ketham’s on the right has the zodiac signs interact with the body, similarly to the earlier Hans Schönsperger example. Ketham’s includes text labels that describe each sign, its corresponding month or planet, and the body part it correlates with. Prüss’ almanac, a calendar which contained astrological charts for the year, would have been targeted at the general book-buying public, whereas Fasciculus Medicinae was specifically made for the learned man who studied the ‘science of the stars’ at university.

As illustrated by these zodiac men, the relationships between sign and body are as follows:

Table listing zodiac signs alongside associated body parts, qualities and temperament, and modality. It uses black text on a white background with four columns labelled Zodiac, Associated body part, Qualities and temperament, and Modality, detailing elements like Aries linked to head and face with a fire temperament and cardinal modality.

With knowledge of the celestial-body relationships, we can now transport ourselves to the sixteenth century to see how astrological medicine was applied in common medical practice, including diagnosis, prognosis, and treatment.

A local physician receives correspondence from a patient experiencing head pain, giddiness (dizziness), and eye strain. Like today, healthcare began in the home, so the patient would have tried a variety of homemade painkilling and humour-balancing treatments before requesting professional help. The physician calls on the patient, carrying with him a medical chest or bag containing pre-made tinctures, a casebook, and an almanac. After checking the patient’s head for any physical or noticeable injuries, the physician reviews the symptoms and asks an important question: when did the pain begin? His almanac would allow him to access general astrological prognostications of the local area or specific social groups, however for a more precise diagnosis and prognosis, the physician would have to create a ‘decumbiture chart’.

A woodcut illustration of a diagram. In the centre is a square, surrounded by another, larger square turned 45 degrees, surrounded by another, larger square. This creates a series of twelve to the surrounding the larger square, each with text of what astrological house the number triangle corresponds to. — A decumbiture chart from Joseph Blagrave, *Blagraves astrological practice of physick* (London: 1671), page 30. (Credit: Wellcome Collection, Public Domain).

A decumbiture chart recorded the ‘time of decumbiture’, i.e. the time that a patient became bed-bound with their medical affliction. The physician-astrologer would use the time of decumbiture to determine the position of celestial bodies when the illness struck by using a volvelle - an astrolabe made from paper - and then would plot the findings onto the chart. Each of the twelve triangles represents an astrological house: imaginary segments of the celestial sphere that are defined by an observer at a given place and time. Each house has a distinct influence on a person, and, for the purpose of this article, we will be focusing on the sixth house: ‘his sickness and servants’ (as seen on the bottom right-hand corner of Blagrave’s chart above).

It was probable that the physician would find the sign of the afflicted body part, in this case Aries, in or on the cusp of the sixth house. The position of the fiery, cardinal zodiac in the house that governed sickness had caused yellow bile - the humour influenced by Aries – to flow to the head and become concentrated in that area. It was this excess of yellow bile that caused the physical pain of the malady. The other consideration would be the position of the moon on the decumbiture chart. If it also happened to be in the sixth house or close to a malefic planet, such as Mars or Saturn, the prognosis was unlikely to be positive. The sun or moon next to Jupiter, the “greater benefic”, however, could suggest that relief was near.

A rare and remarkable series of case notes by sixteenth-century physicians Simon Forman (1552-1611) and Richard Napier (1559-1634) survives at Cambridge University and has been meticulously analysed, itemised, and digitised by Lauren Kassell and her colleagues. Decumbiture charts from these casebooks put the knowledge from the zodiac man into practice.

[left] A hand-drawn diagram of a square with a cross drawn through it. In the middle of the square is another square at a 45-degree angle. This creates a series of twelve triangles. Inside and on the lines of the triangles are astrological symbols and numbers.

[right] A hand-drawn diagram of a square with a cross drawn through it. In the middle of the square is another square at a 45-degree angle. This creates a series of twelve triangles. Inside and on the lines of the triangles are astrological symbols and numbers. — Left: Decumbiture chart of Agnys Vaile of Stonystratfrod, 31 May 1600, detail of CASE10738. (Courtesy of Casebooks digital edition CASE10738). Right: Decumbiture chart of Ralfe Vines, 16 September 1598, detail of CASE11692. (Courtesy of Casebooks digital edition CASE11692). (Both under CC BY-NC 3.0).

The chart on the left shows the decumbiture chart of Agnys Vaile, who complained of a ‘head megrim syde’; Aries sits on the cusp of the sixth house at 13 degrees. The degree of the zodiac relates to the position of the sign in the house - 1 being the start and 30 the end – however, each zodiac group also had ‘critical degrees’, moments when the sign’s energy is concentrated, and their influence is expressed with heightened intensity. Unfortunately for Agnys, 13 degrees was a critical degree for Aries, and thus exacerbated the pain of the fiery migraine.

The chart on the right shows a similar case of Ralfe Vines, a 13-year-old boy complaining of giddiness in his head, pain in the eyes, and drowsiness. Alike Agnys, Aries is present in the house of sickness, likely causing the onset of the pain. There is another indication on their charts, however, that the outlook was grim. On the middle left is the first house, also known as the ‘ascendant house’, the ‘house of self’, and the marking of initiative. What was positioned in the first house would indicate the prognosis of the ailment. Positioned in both first houses are Scorpio and Mars; whilst Scorpio was generally considered a positive sign of regeneration, Mars was associated with all things perilous, from raging fevers to disastrous pestilence. The sun, positioned next to Mars in Ralfe’s chart, exacerbated the malefic planet’s influence, and sadly, Richard Napier records that he died soon after.

Let’s return to our physician. He has drawn up a decumbiture chart for the patient experiencing head pain and found similar results to the Napier examples; Aries is present in the sixth house, close to the moon, and Mars ascends in the first house. The patient is in near-mortal peril, and whilst purgatives and cool/wet remedies would be prescribed, a more extreme treatment was necessary: a visit from the barber-surgeon.

It was the job of the barber-surgeon to make incisions into the body to 'let blood’ and release the excess humours, one of the most popular medical treatments of the medieval and early modern periods. Despite their non-academic training, astrological knowledge was necessary to a barber-surgeon's profession, as the success of a blood-letting procedure depended on the position of celestial bodies. Ideally, the incision should be as close to the site of pain as possible but not be made in the month of the ailment’s zodiac or when the moon is too close to the sign. If blood was let near the head of our patient in any of these circumstances, the strength of the celestial influence would cause either a further imbalance or, worse, fatality, from excessive blood loss. An example of an acceptable time to let blood near the head can be seen in the case of John Coleman, who was ‘crazed in his brayne’ and treated with ‘bleeding from the head vein’; Aries is far away from both the sixth house (it is positioned in the eleventh) and the moon. The practitioner, Mr Robert Wallis, does not record the outcome.

A hand drawn diagram of a square, surrounded by another, larger square turned 45 degrees, surrounded by another, larger square. This creates a series of twelve to the surrounding the larger square. In the centre of the square ‘frantick’ is written, and inside and on the lines of the triangles are astrological symbols and numbers. — Decumbiture chart of John Coleman of Little Brickhill, 14 March 1620, CASE50379. (Credit: Casebooks digital CASE50379 under CC BY-NC 3.0).

Our example patient represents many early modern contemporaries, who were part of a society deeply conscious of their health and physical wellbeing. The zodiac man and decumbiture charts illustrate how astrology was inextricably linked to medicine in this period, especially by physicians, who considered themselves the premier healthcare regulators. Whilst this may seem archaic or even mystical today, the understanding of celestial movements, astrological prognostication, and humoral theory was grounded in centuries of practice and regarded as the pinnacle of medical theory for all social strata, from the learned man to the tradesman barber-surgeon. The numerous examples of the zodiac man in printed medical texts and almanacs attest to its wide social acceptance and understanding by the general public, which would remain until the rise of empirical science in the mid-eighteenth century.