Message #107985

[Bianca]

It is important to remember that one of the important reasons for studying astrology in the Latin West was medicine: parts of medical prognosis and treatment were determined by astrological information.

For instance, whether a disease 'turned' (on 'critical days') better or worse depended on the state of the patient's body and whether it was an astrologically favourable moment.

Bloodletting, a medical treatment intended to rectify the imbalance of bodily humours, was regulated
by the position of the moon, which was considered to exert greatest influence over the human body.

For instance, every sign of the zodiac was considered to rule a part of the human body:
the Saggitarius ruled the thighs, Pisces the feet, and so on.

When the moon was in the zodiac ruling a particular part of the body, bloodletting from that part was to be avoided, since the attraction of the moon might cause excessive bleeding. Numerous medical manuscripts and almanacs include the figure of the 'zodiac man' as a reminder of the specific influence of the moon. In addition, the power of the moon's pulling power varied by its phases, and thus almanacs usually showed the phases of the moon.

Thus, students of medicine at Bologna, for instance, learnt astrology for four years, including grounding in Euclid's geometry and Ptolemy's Almagest.

In addition, they learnt how to use instruments such as the astrolabe and the quadrant, and were taught how to use the Alfonsine Tables along with their canons.

The instruction to use astronomical tables indicates that students, or future practitioners of medicine were not expected to calculate afresh planetary positions each time they needed to make a prognosis or conduct blood-letting.

Several manuscripts for physicians contain short-cut tables or volvelles (paper discs) in order to establishing planetary positions and phases of the moon. More frequently, practitioners relied on calendars which listed the necessary astrological information.

Thus mathematics professors at Bologna were required to compile the official prognostication in order
to ensure the dissemination of proper and accurate astrological knowledge. The need for some mastery in astrology for the study of medicine explains why so many teachers of mathematics or astronomy had medical degrees or went on to become physicians, including the most famous astrologer of the Early Modern period, Nostrodamus.

The works of Copernicus and Regiomontanus, and contemporary expectations and reactions to them, also needs to be understood in this light: developments in astronomy were inextricably linked with, and were believed to have, implications for astrology. Astronomical developments did not necessarily mean the demise of astrology.