Medieval Astrology and the Arabic Renaissance: From Egyptian Days to the House of Wisdom

Donato in a 12th-century manuscript includes instructions on how to calculate a person's birth zodiac sign from the difference between their name and their mother's name. If the difference in letters equals four, then they were born in the fourth sign, five in the fifth, and so on. To this fatalistic barbarization of medieval astrology are added the Egyptian days, which were a deformation of an Egyptian doctrine of electoral astrology in which zodiacal degrees were indicated as favorable or unfavorable in relation to the practices intended to be performed. In the medieval context, however, only two extremely unfortunate days per month are remembered, which are indicated as Egyptian days, heirs of the days of the Egyptian plagues, and called the days "that God brought into the world without mercy." On these Egyptian days it was forbidden to perform bloodletting on men or beasts, just as it was inadvisable to undertake a journey, pick plants, or undertake a legal case. In particular, three of these days in April, August, and December were considered extremely ominous, and getting sick or taking a potion on one of these days would surely mean a rapid death. Being born on one of these days would mean a bad and painful death. Finally, since these three days celebrated the anniversary when the Egyptian people were poisoned with the Pharaoh, the very act of drinking water constituted an incredible danger on these three days: "If one drinks water on these three days, they will die in forty days." Although the circulation of a higher astrology generally referring to Firmicus Maternus is attested in certain cultural environments, the astrology of the 9th, 10th, and 11th centuries before the spread of Arabic writings is therefore a fatalistic astrology extremely simple in methods and poor in content. It is essentially superstitious in the sense that it consists in the barbarization and survival of some practices of which all original content and meaning has been lost. While Astrological Europe was prey to superstitious fatalism, in Arabia the foundations for technical and scientific renaissance were being prepared. With a coup d'état, Abu al-Abbas had managed to seize the caliphate by driving out the previous caliph to Spain, giving rise to the caliphate of al-Andalus. With the new caliphate, a new capital became necessary to become the center of the kingdom. Al-Mansur founded the new capital. On July 30, 763, according to the rules of traditional electoral astrology, the new capital of the Abbasid caliphate was founded with the name Baghdad, meaning "God has given." Four gates surround the city in relation to the four cardinal points and the four powers that rule the universe. The purpose of the Abbasids was to found a new capital in the image of the world. To place the birth of the future capital of the kingdom under the protection of Jupiter, lord of the horoscope, was Ma'shallah, who would become the most important astrologer of Caliph al-Mansur. The same year as the foundation of Baghdad, al-Mansur's son was born, Harun al-Rashid, who in turn became caliph in 786, beginning one of the most prosperous periods of the caliphate. Under his reign, both arts and sciences flourished significantly along with a notable strengthening of the political and military system. From this period are the friendly relations between Harun al-Rashid and Charlemagne reported by European chronicles for the curious diplomatic gifts that the caliph made to the French king. Overall, Harun al-Rashid distinguished himself as a skilled politician and just king, so much so that he became the protagonist of numerous stories from the Thousand and One Nights. The political foresight of Harun al-Rashid made him understand the unique role that the Arab people possessed at that moment, finding themselves as a meeting point and crossroads of numerous cultures and on the threshold of the collapse of numerous traditions whose heritage they could collect, becoming the cultural, political, and economic center of the Mediterranean. With this in mind, Harun al-Rashid founded the Bayt al-Hikma, or House of Wisdom, a library destined to become the undisputed cultural and scientific center of the 9th and 10th centuries. During his caliphate, Harun al-Rashid decided, under the advice of his vizier Yahya ibn Khalid of the Barmakid family, to found a vast personal library oriented toward collecting the writings of the Greek and Persian tradition. The Barmakid family had an important role in this cultural context that is not entirely clear. The origins of the family trace back, according to some Islamic chroniclers, to Barmak, high priest of the fire cult according to Zoroastrian precepts in the Nowbahar area, probably heir to a tradition of Buddhist character. Subsequently, with Khalid ibn Barmak, the family united its destiny with the Abbasid caliphate, occupying prominent positions in the political and economic government of the empire. Khalid's son, Yahya, then became the tutor of the son of Caliph al-Mahdi, namely Harun al-Rashid, who rewarded him with unlimited powers over his empire until 803 - that is, 6 years before his own death - when, for reasons still unclear...