De medicorum astrologia, 1483
Printed in Padua, where teachings in astrological medicine were particularly important, this tract, attributed to Hippocrates, includes chapters on the effects of the moon and each sign of the zodiac on the body. Particularly notable are the chapters on Aries and Taurus, with heavy use of astrological symbols throughout. Still recognized as constellations today, the zodiac—or, to astrologers, "houses"—includes Capricornus, Aquarius, Pisces, Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpius, and Sagittarius. Although the boundaries of the zodiacal constellations have changed over the years, their identification has deep antiquity. The Babylonians recognized them, implying that the naming of star patterns may extend far into the ancient past. Because the sun, moon, and planets appear to move against the background of stars represented by these constellations, the zodiac became imbued with mythical and mystical associations and power over human affairs. For horoscope casting, zodiacal houses are important, not the specific astronomical constellations. Astrologers have not been consistent historically in their recognition of the zodiacal constellations or in the significance of planetary configurations. For instance, some astrologers substitute a system of lunar mansions in lieu of the zodiac, depending on the location of the moon at any moment. Medically-related horoscopes were cast not only throughout the Greco-Roman classical world, but in Muslim lands as well.