Medieval Astrology and the Arab Renaissance

Mercury (Wednesday), Jupiter (Thursday), Venus (Friday), Saturn (Saturday), Sun (Sunday). The manuscripts in which lunar days were combined with the elaboration of the letters of the name were called Spheres of PetOsiris or sometimes Pythagorean prognostics. In reality, many explanations are provided by 11th-century astrologers to justify the Egyptian days. The association with the Egyptian plagues is attested, for example, by Bernard Gordon, but other authors provide other explanations such as the recurrence of bloody sacrifices by the Egyptians.

A legal case. In particular, three of these days in April, August, and December were considered extremely unlucky, and falling ill or taking a potion on one of these days would surely have meant a quick death. Being born on one of these days would have meant a bad and painful death. Finally, since these three days celebrated the anniversary of when the Egyptian people were poisoned with the Pharaoh, the very act of drinking water on these three days posed incredible danger: "If one drinks water on these three days, he will die in forty days." Although the circulation of a higher astrology generally referring to Firmicus Maternus is attested in certain cultural circles, nevertheless the astrology of the 9th, 10th, and 11th centuries before the diffusion of Arabic writings is still a tendentially fatalistic astrology, extremely simple in methods and poor in content. It could rightfully be called superstitious in the literal sense of the term if one refers to the survival of certain practices and techniques whose original content and meaning have been lost.

The Arab Renaissance

On July 30, 763, according to the rules of traditional electoral astrology, under the protection of Jupiter, lord of the horoscope, the new capital of the Abbasid caliphate was founded with the name Baghdad, meaning "God has given." Four gates surrounded the city in relation to the four cardinal points and the four powers that govern the universe. The Abbasids' goal was to found a new capital in the image of the world. To establish the birth of the future capital of the kingdom was Ma'shallah, who would become the most important astrologer of Caliph al-Mansur. The same year as Baghdad's foundation, al-Mansur's son Harun al-Rashid was born, who himself became caliph in 786, beginning one of the most prosperous periods of the caliphate. Under his reign, both arts and sciences developed significantly, and there was a notable strengthening of the political and military system. From this period are, for example, the friendly relations between Harun al-Rashid and Charlemagne reported in European chronicles as well for the curious diplomatic gifts that the caliph gave to the French king. Overall, Harun al-Rashid distinguished himself as a skilled politician and just king so much that he became the protagonist of numerous stories from the Arabian Nights.

Harun al-Rashid's political foresight made him understand the unique role that the Arab people possessed at that time. 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.

The House of Wisdom

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 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 date back, according to some Islamic chroniclers, to Barmak, chief priest of the fire cult according to Zoroastrian dictates 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 Caliph al-Mahdi's son, 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 completely obscure, al-Rashid had him imprisoned along with most members of the Barmakid family.

Raised under the influence of the Barmakids, Harun al-Rashid had from childhood a strong inclination toward the study of the Greeks and sympathy for the Persian cultural environment. The education he received thus led him to actively favor the study and translation of Greek and Persian authors, gathering a large number of scholars and translators capable of bringing together in one place the various manuscripts obtained from Byzantium and India. In this place, critical translations of the Siddhanta were thus begun, and subsequently of Ptolemy's Almagest as well as Euclid's Elements, just to mention a few. The Bayt al-Hikma rapidly became a cultural center of great importance, especially during the period of Caliph al-Mamoun's caliphate, son of Harun al-Rashid. Here the foundations for the Arab cultural-scientific revolution were established, starting from translations of Greek classics such as Galen, Hippocrates, Ptolemy, Euclid, Aristotle, Plato, Archimedes.