Medieval Arabic astrology represents a vital missing link in the history of the western tradition. With the collapse of the Roman Empire in AD 476, Europe entered its ‘dark ages’ when knowledge of classical science and philosophy was lost to the west for several centuries. The Christian church eventually established the monastic system as a means of promoting learning, but even then the philosophers of Pagan times were viewed with suspicion by the church fathers. Astrology, having been denounced by Saint Augustine, was regarded as the work of the Devil. Yet amongst the Muslim enemies of Christendom – the Saracens, Moors and Turks – the philosophers of the ancient world were revered as wise men from a golden age of enlightenment and learning. At its most exalted level, astrology was seen as a precious remnant from a time when people had lived in conscious harmony with their celestial origins.
The expansion of the Islamic Empire began in AD 622 with the flight of the Prophet Mohammed from Mecca. Within a century, the Islamic Empire dominated the whole of the Middle East and extended eastwards across northern India to the borders of China, and westwards across Asia Minor, north Africa, and – with the Arabic conquest of Spain and Sicily – into Europe itself. When the period of military conquest was over, Islamic scholars became enthusiastic admirers of the intellectual and cultural achievements of the great civilisations of the past.
Astrology entered the Islamic tradition from three directions: Persia, India and Greece. The first major astrological text to be translated into Arabic came from India. This was the Siddhanda, translated in Baghdad around 770 and known to the Arabians as the Sindhind. Even so, the Greek contribution to Arabic astrology was by far the most important. The conquests of Alexander the Great had spread Greek civilisation right across the ancient world; consequently Greek ideas had powerfully influenced the indigenous astrology of Persia and India. The great cultural centre of Alexandria in Egypt – the ‘hub of the world’ in Hellenistic times – fell to the Arabs in 642 and the thousands of manuscripts preserved in its famous library opened up the intellectual legacy of Greece to Islamic scholars. In the early ninth century, al-Ma’mun, the Caliph of Baghdad, founded an academy called the House of Wisdom which became the centre of an ambitious project to translate all the surviving texts of antiquity into Arabic. Aristotle’s physics, the astronomy of Hipparchus and Ptolemy’s astrology revolutionised Islamic science.
The Arabs had always been interested in astronomy. The stars were used for navigation in the desert, and the Moon still regulates the Islamic calendar. The discovery of the theories of Ptolemy and Hipparchus, however, brought a new scientific rigour to the study. This was further stimulated by contact with India and the advanced techniques of Indian mathematics. The numeric symbols 1, 2, 3, 4, etc., and the decimal system of notation based on the symbol zero – which was unknown to the Greeks and Romans – came originally from India, as did algebra and the sine function in trigonometry (the other five trig functions were Arabic inventions). These innovations brought unprecedented accuracy to Arabic astronomy. The first great Islamic observatory was founded in 829 by Caliph al-Ma’mun at Baghdad and equipped with observing instruments modelled on those described by Ptolemy and Hipparchus. Gradually designs were improved until eventually the precision of Arabic astronomy surpassed anything achieved by the Greeks.
The philosophical foundation to Arabic astrology was laid down by al-Kindi (d.866), tutor and physician to al-Ma’mun and regarded as one of the most learned men of his time. Drawing upon classical ideas, al-Kindi evolved a philosophy of ‘cosmic sympathy’ linking the macrocosm and microcosm. Correspondences between celestial configurations and events on Earth demonstrated the wholeness of Creation, while the theories of Aristotle and Ptolemy provided a respectable scientific framework. The fatalism implicit in astrology was broadly compatible with the teachings of Islam, which means ‘submission’ to the Will of Allah. Astrological symbolism became an important element in the esoteric doctrines of the Sufi mystics, though more orthodox Islamic theologians argued that since Allah was all-powerful, astrology was irrelevant at best; at worst it was a dangerous delusion bordering on the magical and demonic. Similar objections were raised by Christian theologians when astrology began to filter into medieval Europe through the Islamic universities of Moorish Spain.
Around AD 1000 the Mathesis of Firmicus Maternus became the first classical text to be translated from Arabic into Latin. It was followed by a flood of astrological, scientific and philosophical works over the next two centuries that revitalised all aspects of European learning. Original Arabic texts mixed in with the classical authors gave a distinctly Arabic flavour to medieval astrology that can be traced down to the 17th century. Albumazar (abu-Ma’shar), Alfraganas (al-Farghani) and Alkindus (al-Kindi) are among the Arabic astrologers whose rules and aphorisms are quoted in Lilly’s Christian Astrology. With the historical enmity between Islam and Christianity, however, it was fashionable amongst all European astrologers to regard any dubious methods as Arabic distortions of classical doctrines. As an extreme example, the high-minded and progressive Kepler dismissed horary and most other traditional practices as ‘Arabic sorcery’, though horary and even the much-maligned ‘Arabian parts’ were well-known in classical astrology.
Virtually all the Arabic texts that influenced medieval astrology remain in Latin translation, making them inaccessible to most astrologers today. A rare exception is al-Biruni’s Book of Instruction in the Elements of the Art of Astrology written at Ghaznah, Afghanistan in 1029. It was not among the texts that surfaced in medieval Europe, and we owe our present knowledge of it to R. Ramsey Wright’s 1934 translation from Persian and Arabic sources. While al-Biruni was not a direct influence upon European astrology, he was highly regarded throughout the Islamic world for his encyclopaedic writings. His textbook of astrology gave a concise account of contemporary Arabic methods set against a wider background of 11th century Islamic science and culture.
The Life of Al-Biruni (973-1048 AD)
Abu Rayhan Muhammed ibn Ahmad al-Biruni was born just before sunrise on 4 September 973. His birthplace was the city of Kath (modern day Khiva) situated on the River Oxus in what was then the Principality of Khwarizm and is now Uzbekistan. Not much is known about his early life, though it is said that he knew little of his grandfather and nothing at all of his father. Whatever his family circumstances it must have been apparent from an early age that al-Biruni was an outstanding scholar and scientist. He seems to have been interested in every branch of learning, excelling particularly in astronomy, mathematics, physics, history and medicine. He was also fluent in a number of languages, including Turkish, Persian, Sanskrit, Hebrew and Syriac, as well as Arabic. By the age of 20, al-Biruni had written several acclaimed scientific papers and is known to have conversed and corresponded with his younger contemporary ibn Sina (Avicenna), whose writings were to become widely known in Europe.
While al-Biruni was still in his early twenties, the ruling dynasty of Khwarizm was overthrown by Emir Ma’mun ibn Muhammad of neighbouring Gurganj. Al-Biruni sought refuge at the court of Sultan Nuh ibn Mansur, the overlord of all the bickering princes of the region. There he met Emir Qabas al-Ma’ali who had been temporarily ousted from his own principality. In 998 the Sultan restored Qabas to power and al-Biruni went with him to Gurgan on the Caspian Sea where he remained for several years. During this period he completed his first major work, The Chronology of Ancient Nations.
By 1009 al-Biruni had returned to Khwarizm where he occupied an honourable position as a councillor and court official to the successors of Ma’mun the usurper. In 1017, Ma’mun’s second son was murdered by rebellious subjects and his brother-in-law, Mahmud of Ghazna, invaded Khwarizm to wreak vengeance. Surviving members of the court of Khwarizm were carried off involuntarily to Mahmud’s stronghold at Ghazna in Afghanistan and al-Biruni was taken with them, along with ibn Iraq the mathematician and ibn Khammar the physician. Mahmud was keen to attract learned men to Ghazna to add to the prestige of his court, and was prepared to use any means to get them there. Avicenna had fled from the region several years previously upon receiving one of Mahmud’s threatening ‘invitations’. Al-Biruni, however, seems to have settled quite happily at Ghazna where he was honoured for his great learning and employed as court astrologer to Mahmud and his successors.
Between 1017 and 1030, al-Biruni travelled extensively in India, collecting material for his monumental survey of the history, customs and beliefs of the sub-continent. India was his most highly-acclaimed work during his lifetime. He also produced a major work on astronomy, known as the Masudic Canon, dedicated to Mahmud’s son, Ma’sud. It is said that Ma’sud rewarded him with an elephant-load of silver for the Canon but that al-Biruni returned it to the Treasury. As a technical work of medieval astronomy the Canon is notable for al-Biruni’s approval of the theory that the Earth rotates upon its axis, which suggests that Arabic astronomers were more critical of the theories of Aristotle and Ptolemy than is often assumed. Ma’sud granted al-Biruni a pension that enabled him to devote the rest of his life to his scientific studies and his literary work. As well as the Elements of Astrology, he wrote important books on medicine, geography and physics and translated Ptolemy’sAlmagest into Sanskrit. He died at Ghazna on 13 December 1048, aged 75.
The Elements of the Art of Astrology
Al-Biruni’s Book of Instruction in the Elements of the Art of Astrology was written for Lady Rayhanah, one of the members of the Khwarizm court carried off to Ghaznah by Mahmud in 1017. Virtually nothing is known about her, though R. Ramsey Wright rather patronisingly says, ‘she is marked out among oriental women by her craving for scientific knowledge and by the rare distinction of having a book dedicated to her’.
Al-Biruni’s instructions to Rayhanah were certainly comprehensive. According to Wright, the Elements ‘may be regarded as a primer of 11th century science’. It begins with sections on geometry and arithmetic leading to a thorough exposition of Ptolemaic astronomy that includes a detailed description of the use of the astrolabe. This is followed by sections on geography and chronology. A1-Biruni insists that no-one is entitled to call himself an astrologer without a good knowledge of these ancillary sciences.
He recognises five divisions of judicial astrology. The first, ‘natural’ astrology is concerned with meteorology, earthquakes, floods, and all other ‘vicissitudes and disasters of nature’ . The second is mundane astrology, concerning the rise and fall of kingdoms, battles, revolutions, etc. Individual natal astrology constitutes the third division where, like Ptolemy, al-Biruni was fully aware that considerations of heredity and environment should modify any astrological indications. The fourth division ‘has to do with all human activities and occupations… founded on beginnings or origins’. This would include horary and electional astrology, though this area shades into the fifth division where ‘astrology reaches a point which threatens to transgress its proper limits… where the astrologer is on one side and the sorcerer on the other [and] you enter a field of omens and divinations which has nothing to do with astrology although the stars may be referred to in connection with them.
The picture of Arabic astrology that emerges is very similar to the Greek model as exemplified in the Tetrabiblos though with differing attributions and correspondences to reflect a different cultural environment. Al-Biruni makes frequent comparisons with Indian practices – along with the occasional dry note of disapproval where they offend his sense of propriety. His extensive list of the so-called ‘Arabian parts’ was taken from Abu-Ma’shar though the concept is much older. It was a popular technique amongst Arabic astrologers and became closely associated with them. Al-Biruni lists over 150 parts or ‘lots’ and still complains, ‘it is impossible to enumerate the lots which have been invented for the solution of horary questions… they increase in number every day’. The ‘lunar mansions’ or ‘stations of the Moon’ is one purely Arabic concept, though here al-Biruni limits himself to an astronomical description only. It is the astronomical dimension to al-Biruni’s astrology that distinguishes it from the classical texts, reflecting the advances and refinements of Arabic science. His discussion of the subtleties of interpretation arising from different phases of the planetary orbits puts our present understanding of ‘accidental dignity’ to shame.