Byzantium inherited the rich astrological tradition of Late Antiquity, especially that of Alexandria, where even in the 6th century A.D., astrology was taught in philosophical schools. The great number of Byzantine astrolgical MSS, which preserve works of famous authors and many anonymous treatises, shows the survival and continuity of astrology in Byzantium. Through medical astrology pysicians can better understand the temperament of an individual man and find out about his bodily constitution and psychic faculties, his inclination to chronic and acute diseases, the possibilities of curable or incurable cases, and finally the periods of lmajor danger for his health. They can conjecture about the evolution of a disease, choose a favourable time for an operation, or initiate a cure.