Astrology consists of several pseudoscientific systems of divination based on the premise that there is a relationship between astronomical phenomena and events in the human world. Many cultures have attached importance to astronomical events, and the Indians, Chinese, and Mayans developed elaborate systems for predicting terrestrial events from celestial observations. In the West, astrology most often consists of a system of horoscopes purporting to explain aspects of a person's personality and predict future events in their life based on the positions of the sun, moon, and other celestial objects at the time of their birth. The majority of professional astrologers rely on such systems.
After the conquest of Alexandria in the 7th century, astrology was taken up by Islamic scholars, and Hellenistic texts were translated into Arabic and Persian. In the 12th century, Arabic texts were imported to Europe and translated into Latin, helping to initiate the European Renaissance, when major astronomers including Tycho Brahe, Johannes Kepler and Galileo practiced as court astrologers. Astrological references appear in literature in the works of poets such as Dante Alighieri and Geoffrey Chaucer, and of playwrights such as Christopher Marlowe and William Shakespeare.