The last pagan scholar to head the Platonic academy in Alexandria was Ammonius, who directed it from 485 until his death sometime between 517 and 526. Ammonius was a distinguished philosopher, astronomer and mathematician, known for his commentaries on Aristotle. His most famous students were the mathematician Eutocius of Ascalon and the philosophers John Philoponus and Simplicius of Cilicia. Philoponus, a Christian, succeeded Ammonius as head of the Neoplatonic school in Alexandria. Simplicius, who seems to have remained a pagan, moved to Athens and joined the ancient Platonic Academy.
Eutocius dedicated his commentary on the first book of Archimedes’ On the Sphere and Cylinder to Ammonius. He later wrote commentaries on two more works of Archimedes – the Measurement of a Circle and On Plane Equilibria – as well as on the first four books of the Conics of Apollonius. His commentaries proved to be crucial in the survival of these works.
Simplicius is famous for his commentaries on Aristotle, which contain much valuable material otherwise unavailable, including fragments of the pre-Socratic philosophers. Some of his Aristotelian scientific ideas were criticised by Philoponus, who had succeeded Ammonius as head of the Platonic school in Alexandria.
Thus in the twilight of antiquity a great debate took place about the Aristotelian world-view, which was attacked by Philoponus and defended by Simplicius. The most interesting part of this debate focused on why a projectile, such as an arrow, continues moving after it receives its initial impetus. Philoponus rejected the Aristotelian theory presented by Simplicius, which was that the air displaced by the arrow flows back to push it from behind, an effect called antiperistasis. Instead, Philoponus suggested that the arrow, when fired, receives an ‘incorporeal motive force’, an idea that was revived in medieval Europe as the ‘impetus theory’, Philoponus also wrote a treatise on the astrolabe, the instrument later used by all Arabic astronomers for their observations and calculations.
After Constantine shifted the capital of his empire in 330 to Byzantium on the Bosphorus, thenceforth to be called Constantinople, Christianity became the state religion of the realm that later came to be called the Byzantine Empire. Constantine had already organised the first ecumenical council of the church in 325 at Nicaea. The second ecumenical council was held at Constantinople in 381, the third at Ephesus in 431, and the fourth in 451 at Chalcedon, in the Asian suburbs of the capital, the principal business at all of these synods being doctrinal matters, particularly concerning the nature of Christ. The bishops at Chalcedon formulated what became the orthodox Christological doctrine, i.e., that Christ was both human and divine, his two natures being perfect and indivisible though separate. At the same time they condemned as heretics those who thought differently, the Monophysites, whose believers, principally in south-eastern Asia Minor, Syria, Mesopotamia, Persia and Egypt, then formed their own schismatic churches.
Many of the early translations were done by the schismatic Christians in south-eastern Anatolia, Syria, Mesopotamia and Persia, who spoke Syriac, a Semitic language deriving from Aramaic. The Syriac-speaking Christians were members of the Nestorian, Jacobite and other eastern churches, which had split with the Greek Orthodox patriarchate in Constantinople on doctrinal matters. These eastern Christians had assimilated secular Greek learning through their monasteries and schools, most notably those of the Nestorians at Edessa (Turkish Urfa) and Nisibis (Turkish Nusaybin) in northern Mesopotamia. Among the books used at these schools were Greek treatises translated into Syriac, most notably the logical works of Aristotle.
The school at Edessa, founded in the mid-fourth century AD, was the centre of higher theological studies among the Syriac-speaking eastern Christians. During the following century the scholars at Edessa were followers of Nestorius, patriarch of Constantinople (r. 429–31), whose Christological doctrines were condemned as heretical in 431 by the Council of Ephesus. This led the emperor Zeno to close the school at Edessa in 489, whereupon the Nestorian scholars moved eastward to Nisibis, which was then in Persian territory.
The eastward migration of Nestorians eventually brought them to the Sasanid capital at Jundishapur in western Persia, where in the late fifth century they joined the faculty of a medical school that had been founded by King Shapur I (r. 241–72). There the Nestorian faculty taught Greek philosophy, medicine and science in Syriac translations.
Modern historians consider the sixth century to be a watershed in the history of the empire, which from that time on they tend to call Byzantine rather than Roman, though it is usually the transfer from Nikomedia to Constantinople in 324 that signalled the beginning of the split. As the great churchman Gennadius was to say in the mid-fifteenth century, in the last days of the Byzantine Empire: ‘Though I am a Hellene by speech yet I would never say that I was a Hellene, for I do not believe as Hellenes believed. I should like to take my name from my faith, and if anyone asks me what I am I answer, “A Christian.” Though my father dwelt in Thessaly I do not call myself a Thessalian, but a Byzantine, for I am of Byzantium.’
The peak of the Byzantine Empire came under Justinian I (r. 527–65), who reconquered many of the lost dominions of the empire, so that the Mediterranean once again became a Roman sea. Justinian also broke the last direct link with the classical past when in 529 he issued an edict forbidding pagans to teach. As a result the ancient Platonic Academy in Athens was closed, ending an existence of more than nine centuries, as its teachers went into retirement or exile.
Those who went into exile included Damascius, the last director of the Academy, along with Isidorus of Miletus, who had been his predecessor, and Simplicius of Cilicia. They and three other scholars from the Academy were given refuge in 531 by the Persian king Chosroes I (r. 531–79), who appointed them to the faculty of the medical school at Jundishapur. The following year the six of them were allowed to come back from their exile, five of them returning to Athens, while Isidorus took up residence in Constantinople.
Justinian appointed Isidorus to be chief of the imperial architects, along with Anthemius of Tralles, their task being to design and build the great church of Haghia Sophia in Constantinople, whose foundation was laid in 532. Anthemius died during the first year of construction, but Isidorus carried the work through to completion, after which Justinian dedicated the church on 26 December 537. Haghia Sophia, which some consider to be the greatest building in the world, still stands today, a symbol of the golden age of the Byzantine Empire under Justinian.
Isidorus and Anthemius had studied and taught the works of Archimedes and the Archimedean commentaries of Eutocius of Ascalon. Isidorus was apparently responsible for the first collected edition of at least the three Archimedean works commented upon by Eutocius – On the Sphere and Cyclinder, On the Measurement of the Circle and On the Equilibrium of Planes – as well as the commentaries themselves.
Isidorus of Miletus was the last physicist of antiquity, for by his time the ancient Graeco-Roman world had vanished, supplanted by the new order represented by the Christian Byzantine Empire. Byzantium would soon begin its long struggle with invaders from both West and East, the latter including the triumphant armies of Islam, leaving many of the other great cities of the Greek world in ruins. The long night of the Dark Ages had begun, and for the few who could remember the classical past it would have seemed that Greek philosophy and science had come to an end, with the famous schools of Athens closed and the Museum and Library of Alexandria destroyed, the last philosophers and scientists passing away without successors to perpetuate the ideas that had been given wing by the first physicists in Miletus more than a thousand years before.
Despite Justinian’s closure of the Platonic Academy, classical Greek culture survived in Byzantium, not only in Constantinople but also in the south-eastern provinces of the empire, particularly among the schismatic Christians, who had translated Greek works into Syriac.
The best of the early Syriac translators was Sergius of Reshaina (d. 536), a Monophysite priest and physician who had been educated in the Platonic school of Ammonius in Alexandria His translations from Greek into Syriac included some of Aristotle’s logical works, which were at about the same time being rendered from Greek into Latin by Boethius. He also wrote two works of his own on astronomy, On the Influence of the Moon and The Movement of the Sun, both undoubtedly based on Greek sources. Sergius was characterised by a later Syriac writer as ‘a man eloquent and greatly skilled in the books of the Greeks and Syrians and a most learned physician of men’s bodies. He was orthodox in his opinions... but his morals [were] corrupt, depraved and stained with lust and avarice.’
During the reign of Khosrow I there was a distinguished scholar in the court known as Paul the Persian, who is said by the later Christian philosopher Bar Hebraeus to have written an ‘admirable introduction to the dialectics (of Aristotle)’. It is generally agreed that this is identical to the Treatise on the Logic of Aristotle the Philosopher Addressed to King Kosrow, which is extant in a Syriac manuscript in the British Museum. The Treatise contains an introduction to philosophy in general, an introduction to Aristotle’s logical works and summaries of the individual books of the Organon studied in the Syrian tradition. Paul translated the last five books of the Organon into Syriac, which were later rendered into Arabic, making him an important link connecting the last Alexandrian scholars with the first philosophers who would emerge in the Islamic world. Khosrow sponsored the publication in Pahlavi of the Royal Astronomical Tables, apparently based on Indian and Greek sources, which would subsequently be used in the first Islamic writings on astrology and astronomy. (Ptolemy’s Almagest had been translated into Pahlavi in the third century, and was later translated into Arabic, first by al-Hajjaj ibn Matar.)
Three Indian astronomical works of the early medieval period are referred to by al-Biruni, though we do not know whether these works were translation into Arabic or whether the early Abbasid astrologers used a Pahlavi version. The earliest of these, the Aryabhatiya, was written in 499 by Aryabhata; the second is the Khandakhadyaka of Brahmagupta, dated 665; the third is the Zij al-Sindhind (a zij is an astronomical handbook with tables), from the end of the seventh century or the beginning of the eighth. According to Regis Morelon, ‘These texts are based on the yearly cycles corresponding to the Indian cosmology, and their scientific tradition is linked with an earlier period of Hellenistic astronomy than that of Ptolemy; they thus preserve a certain number of elements that can be traced back to the time of Hipparchus.’
The Aryabhatiya and Khandakhadyaka are works of mathematical astronomy. The principal contribution made by Aryabhata is his introduction of place-value notation, a version of a system first used in ancient Babylonia. Brahmagupta’s greatest contribution were in algebra, particularly in indeterminate analysis, where he extended the work of Diophantus.
A distinguished Syriac scholar of the early medieval period was Severus Sebokht (d. 667), a Nestorian bishop who wrote on both scientific and theological subjects. His scientific writings included works on logic (now mostly fragments), a commentary on peri hermeneias by Paul the Persian, and treatises on astronomy and the astrolabe. He was also one of the first Syriac scholars to use the so-called Hindu-Arabic number system. Writing in 662, he praises the Hindus and ‘their valuable methods of calculation, and their computation that surpasses description’. He goes on to say that ‘I only wish to say that this computation is done by means of nine signs.’
The Islamic calendar begins in 622, though the Islamic faith is generally regarded to have begun in 610, when the Prophet Muhammed started to receive revelations from God. Arab armies under his successors, the first caliphs, conquered all of the Arabian peninsula in 634, Syria in 637, Egypt in 639, Persia in 640, Tripolitania in 647 and the Maghrib, or north-west Africa, in 670. An Arab fleet besieged Constantinople in the years 670–4 but failed to capture the Byzantine capital. During the next half-century Muslim armies conquered Transoxiana and the Sind, extending their dominion into Central Asia and the borders of India, while in the West they conquered much of Spain, known in Arabic as al-Andalus, invading France before they were stopped at Tours in 732 by Charles Martel, though skirmishes continued in the region. Resistance in Iran continued well into the ninth century, and Egypt was only conquered much later.
Mu’awiya became caliph at Jerusalem in 661 and that same year moved his headquarters to Damascus, beginning the Umayyad dynasty. The Umayyad caliphate lasted until 750, when the last of the dynasty, Marwan II, was defeated and killed by the forces of Abu’l-‘Abbas al-Saffah, who had been proclaimed caliph the previous year. Thus began the ‘Abbasid dynasty, which would last for more than five centuries. Abu’l-‘Abbas was succeeded in 754 by his brother Abu-Ja’far al-Mansur, who in the years 762–5 built Baghdad as his new capital, beginning what would prove to be a great period in the intellectual history of Islam.
Baghdad reached its peak as a cultural centre under al-Mansur (r. 754–75) and four generations of his successors, most notably Harun al-Rashid (r. 786–809) and ‘Abd-Allah al-Ma’mun (r. 813–33). According to the historian al-Masudi (d. 956), al-Mansur initiated a programme to have philosophical and scientific works in Greek and other foreign languages translated into Arabic, including ‘books by Aristotle on logic and other subjects, the Almagest by Ptolemy, the Arithmetic [by Nicomachus of Gerasa], the book by Euclid [the Elements], and other ancient books from classical Greek, Byzantine Greek, Pahlavi, Neopersian and Syriac. These were published among the people, who examined them and devoted themselves to knowing them.’
The translation movement had actually begun in the time of the Ummayad caliphate, when some Greek medical works were translated from Syriac to Arabic, mostly by Nestorian and Jacobite Christians as well as Jews. As Dimitri Gutas has pointed out, there were also translations from Greek into Pahlavi, the middle Persian of the Sasanian dynasty, ‘motivated by the belief that all learning ultimately derived from the Avista, the Zoroastrian canonical scriptures’. Thus they felt that Greek science had originated in Persia, and that in translating the works of Aristotle, Euclid, Ptolemy and others they were reclaiming elements of ancient Persian culture.
The historian al-Masudi writes of al-Mansur’s preoccupation with astrology, which led him to employ several astrologers in his court. ‘He had in his retinue Nawbakht the Zoroastrian, who converted to Islam upon his instigation...Also in his retinue were the astrologer Ibrahim al-Fazari, the author of an ode to the stars and other astrological and astronomical works, and the astrologer ‘Ali ibn Isa the Astrolabist.’
Nawbakht the Zoroastrian (d. ca. 777) was a Persian astrologer whose examination of the celestial signs had led him to advise al-Mansur to begin the construction of Baghdad on 30 July 762. His only known work is an astrological treatise called The Book of Predictions.
Ibrahim al-Fazari (d. ca. 777) was the first court astrologer of the ‘Abbasid caliphs. He is credited with being the first Arabic astronomer to construct an astrolabe, the subject of three of his known works. He also worked on problems of calendar reform, which he discusses in an extant poem on the Syrian months. He writes of the determination of time in another extant poem, On the Science of Stars.
Ibrahim al-Fazari’s son Muhammad was an astrologer in the court of al-Mansur, who ordered him to translate the Sanscrit astronomical work known as the siddhanta, of which there are many titles: surya siddhanta, panea siddhanta, paulisha siddhanta, to name a few. In Arabic they were called the Sindhind. According to David Pingree, the Sanskrit manuscript was given to al-Mansur by an Indian scholar who accompanied an embassy from the Sind to Baghdad in 771 or 773. Ibrahim al-Fazari used this and other sources to compile his own set of astronomical handbooks with tables, the Zij al-Sindhind al-kabir, in which, as Pingree notes, ‘he mingled elements from Indian, Pahlavi, and Greek sources into a usable but internally contradictory set of rules and tables for astronomical computations.’ Dimitri Gutas writes that Ibrahim al-Fazari’s translation, together with his own version of the Sindhind, combined with other factors to produce ‘over the centuries the spectacular tradition of Arabic astronomy’.
Ibrahim al-Fazari’s translation has not survived, but it may have been used as a source by al-Khwarizmi in his version of the Sindhind, which has itself survived only in a modified Latin translation. As George Saliba has pointed out regarding al-Khwarizmi’s Sindhind: ‘That his text survived only in a Latin version, and that the others have been all but totally obliterated, clearly indicates the quick neglect of the Indo-Persian tradition.’
‘Ali ibn Isa the Astrolabist was from Harran in northern Mesopotamia, and probably learned astronomy and astrology from ancient Babylonian sources that were still used by the local people, the Sabeans. Despite the fact that ‘Ali ibn Isa was employed as an astrologer, he wrote a Treatise on Refutation of the Art of Predictions of Stars, the earliest known Islamic work rejecting the notion of astrological prognostication. He was also a physician, noted for his Treasury for Opthalmologists, the first important Islamic treatise on the structure and illnesses of the eye, translated into Latin as Tractus de oculis Jesu ben Hali. ‘Ali ibn Isa is credited with being the first physician to suggest the use of anesthesia in surgery.
Nawbakht was succeeded as court astrologer by his son Abu Sahl al-Fadl ibn Nawbakht (d. ca. 815), who was possibly also chief librarian of Harun al-Rashid. Abu Sahl translated works from Persian into Arabic for the caliph, and he also wrote a number of treatises on astrology, most notably Kitab al-Nahmutan. This is the first book in Arabic on astrological history, a dynastic chronicle in terms of cyclical periods of varying lengths governed by the celestial bodies. He writes that ‘The people of every age acquire fresh experience and have knowledge renewed for them in accordance with the decree of the stars and the signs of the zodiac, a decree which is in charge of governing time by the command of God Almighty.’ Abu Sahl’s motive was to show that the ‘Abbasid succession was preordained by the stars and God, and that it was now their dynasty’s turn to renew knowledge.
Two of Nawbakht’s grandsons, al-Hasan ibn Sahl ibn Nawbakht and ‘Abdullah ibn Sahl ibn Nawbakht, served as astrologers at the court of Caliph al-Wathiq, a grandson of Harun al-Rashid. Al-Hasan wrote a treatise on astronomy and also made translations from Persian into Arabic.
Theophilus of Edessa (695–789), known in Arabic as Thiyufil ibn Thuma, was a Nestorian Christian who was court astrologer and military advisor of Caliph al-Mahdi (r. 775–85). He called astrology the ‘mistress of all sciences’, because of the importance of astrological history under the ‘Abbasids and the commissioning of horoscopes by the caliphs. He did translations of astronomical works from Greek into Syriac and also wrote a book on military astrology. Fragments of additional works in Arabic and Greek still exist.
An associate or student of Theophilus named Stephanus the Philosopher also served as astrologer at al-Mahdi’s court. Stephanus visited Constantinople in the 790s, during the reign of Constantine VI (r. 780–97), when he wrote a treatise in praise of astrology. He writes in his treatise that he found nothing of the astronomical and astrological sciences in the Byzantine capital, and thus he took it upon himself ‘to renew this useful science among the Romans and to implant it among the Christians so that they might be deprived of it nevermore’. According to Dimitri Gutas, ‘Stephanus brought with him to Constantinople from Baghdad not only news of scientific developments there but also concrete mathematical and astrological information: an astrological technique described in a work by Theophilus was used by Pancratius, the astrologer of Constantine VI, to cast a horoscope.’
Gutas goes on to suggest that this visit by Stephanus sparked a revival of Byzantine interest in the mathematical sciences, when, ‘after a hiatus of apparently over one hundred and fifty years, Greek secular manuscripts began to be copied again around 800.’ He gives a list of twenty-nine ancient Greek works of science and philosophy copied in Constantinople in the years 800–50, all of which were translated into Arabic, including books by Aristotle, Euclid, Aristarchus and Ptolemy, namely his Almagest. Gutas suggests that this surge of copying was a direct response to the translation movement then underway in Baghdad, as well ‘as an expression of the awareness by Byzantine intellectuals of the scientific superiority of Arabic scholarship and the wish to emulate it’.
One of the most distinguished astronomers in Baghdad during the early ‘Abbasid period was Habash al-Hasib. Habash was born in Merv, in what is now Turkmenistan, and worked in Baghdad during the reigns of caliphs al-Ma’mun and Abu-Ishaq al-Mu’tasim (r. 833–42). He is credited with sixteen works on astronomy and three on mathematics. His best known work is The Damascene Tables, a revision of Ptolemy’s Almagest in which he introduces the trigonometric functions of sine, cosine and tangent in place of the chords used by the Greeks. Habash modified Ptolemy’s tables for the motions of the sun, moon and planets based on his own calculations, which were used by many later Arabic astronomers.
Another renowned astronomer of the early ‘Abbasid period is Ahmad al-Farghani, whose nisba (our equivalent of a last name) comes from his birthplace in Transoxania. Al-Farghani worked in Baghdad during the caliphates of al-Ma’mun, al-Mu’tasim, al-Wathiq (r. 842–47) and al-Mutawakkil (r. 847–61). He is credited with eight works on astronomy, the best known of which is the Kitab fi usul ‘ilm al-nujum – the Book on the Elements of the Science of the Stars – a comprehensive account of Ptolemaic astronomy in descriptive rather than mathematical terms. The Elements was translated into Latin in the twelfth century by both John of Seville and Gerard of Cremona, whose translation was used by Dante for the astronomical knowledge used in the Vita nuova and in the Convivio.
Ptolemy’s Tetrabiblos, the foremost astrological work of antiquity, was translated from Greek to Arabic by the Christian scholar al-Bitriq during the reign of al-Mansur and another Arabic translation was made in the ninth century by Ibrahim al-Salt.
The most prominent astrologer in the early ‘Abbasid period was Masha’allah, a Jew from Basra who was one of those whose examinations of the celestial signs led to the founding of Baghdad. His horoscopes can be dated to the period 762–809, and he served as astrologer to all of the caliphs from al-Mansur to al-Ma’mun. He wrote on every aspect of astrology, most notably an astrological history called the Book of Mysteries, the principal source of information about the Royal Astronomical tables sponsored by Chosroes I. He is credited with twenty-eight books, of which twenty-three have survived. Many of his works were translated into Latin; one was used by Chaucer in his famous treatise on the astrolabe, and he is referred to by Copernicus.
Alchemy was another field in which the ‘Abbasids felt that there was a need for ancient Greek texts to be translated into Arabic. The geographer Ibn-al Faqih al Hamadani quotes a report by al-Mansur’s secretary, ‘Umara ibn Hamza, who spent some time in Constantinople during the reign of Constantine V (r. 741–75). When ‘Umara returned to Baghdad he reported that he had seen the emperor transmute lead and copper to silver and gold using a dry powder he called al-eksir, or elixir, and ‘This was the reason that induced him [al-Mansur] to become interested in alchemy.’
Jabir ibn Hayyan (ca. 721–ca. 815), known in Latin as Geber, is the supposed author of an enormous number of alchemical and other writings. The Jabirian corpus, which appears to be the work of many scholars writing somewhat later than Jabir’s reputed lifetime, represents virtually all that is known of the alchemy in Islam during the early ‘Abbasid period.
One basic concept of Islamic alchemy that had been inherited from the ancient Greeks was the notion that materials like sulfur and mercury could be transmuted into silver and gold. One of the works in the Jabirian corpus proposed a theory in which six metals – tin, lead, iron, copper, silver and gold – were made up of different combinations of sulfur and mercury, and could thus be transformed by adjusting the proportions of the two basic constituents before melting them and mixing them together. Aside from the theory and mystical philosophy behind it, the practice of alchemy demanded a detailed knowledge of the physical properties of the materials involved, and the processes to which they were subjected represent the beginning of chemistry.
Another work in the Jabirian corpus gives the earliest description of the flammability of alcohol, where the author writes that ‘And fire which burns on the mouths of bottles [due to]...boiled wine and salt, and similar things with nice characteristics which are thought to be of little use, these are of great significance in these sciences.’ Thenceforth this property of alcohol appears in alchemical and military treatises, along with the first designs for a portable alcohol lighter.
The Jabirian corpus also includes works on philosophy, astronomy, physics, mathematics and medicine. Among the best known are The Book of Seventy, a collection of seventy treatises on alchemy, most of which were translated into Latin, and The Book of the Balance, which presents the philosophical basis of Jabirian alchemy.
Islamic alchemy also involved astrology, astral cosmology, magic and other occult sciences. These branches of learning came under the heading of the ‘hidden’ (khafiyyah) sciences, in contrast to the manifest (jaliyyah) sciences such as mathematics.
Al-Mansur suffered from dyspepsia, or chronic indigestion, and soon after he moved into his new capital he sought the aid of the physicians at the Jundishapur medical school. His ailment was cured by the director of the hospital, Gurgis ibn Buhtisu, a Nestorian Christian, who came to Baghdad to serve as al-Mansur’s personal physician. The Buhtisus became the leading practitioners of medicine in Baghdad, several generations of them serving as personal physicians to the caliphs. The historian Ibn Abi-Usaybi’a reports that al-Mansur commissioned many translations of Greek works from Gurgis ibn Buhtisu. The translations would have been done from Syriac by Nestorian scholars from Jundishapur, whose medical centre was eventually transferred to Baghdad, becoming the first hospital and school of medicine in the ‘Abbasid capital.
The translation movement was also fostered by the Barmakids, a family who held the most important ministerial positions in the early years of the ‘Abbasid dynasty, retaining power from 750 until 803. Harun al-Rashid’s vizier, Yahya the Barmakid, one of the principal supporters of the translation programme, was from the caravan city of Marw (Merv), capital of Khurasan, the north-eastern province of Persia (now in Turkmenistan). DeLacy O’Leary notes that at the time Marw was ‘one of the centres of Greek scholarship.’ According to O’Leary ‘From Marw came some of the earliest translators of astronomical record, and it would seem that Khurasan was the channel through which astronomical and mathematical material came to Baghdad.’ He goes on to say that ‘Some of the astronomical and mathematical material seems to have been obtained from India, derived from a Greek source in the first place, but probably it was transmitted to the Arabs through a Persian medium, though the actual Persian works whereby it was transmitted are no longer extant.’
Another motivation in beginning the translation programme stemmed from its role in educating the secretaries needed to administer the ‘Abbasid empire. Ibn Qutayba (d. 889), in his Adab al-Katib (Education of the Secretary), enumerates the subjects that a state secretary should learn in order to be qualified for his position, disciplines whose sources were mostly in Greek. The subjects that he mentions include irrigation, surveying, architecture, technology, instrument-making, accounting, geometry and astronomy, the latter in order to measure ‘the varying lengths of days, the rising-points of stars, and the phases of the moon and its influence’.
Yahya is credited by the tenth-century Tunisian scholar ‘Abdallah ibn Abi Zayd with initiating the ‘Abbasid policy of reviving Greek science in Islam, importing Greek books from the Byzantine Empire, and having them translated into Arabic. The translation programme continued under al-Mansur’s son and successor Muhammad al-Mahdi (r. 775–85). Al-Mahdi commissioned the translation of Aristotle’s Topics into Arabic from Syriac, into which it had been translated from Greek. Later the work was translated directly from Greek into Arabic. The motivation for translating the Topics was that it taught the art of systematic argumentation, which was vital in discourse between Muslim scholars and those of other faiths and in converting non-believers to Islam, which became state policy under the ‘Abbasids.
Ja’far ibn Muhammad Abu Ma’shar al-Balkhi was a famous astrologer of the ‘Abbasid period. It was Abu Ma’shar who put astrology on the foundation of peripatetic philosophy, one of the reasons for his importance. His nisba comes from his origin at Balkh in Khurasan (now in Afghanistan), where he was born on 10 August 787. David Pingree describes the rich mixture of peoples and cultures in Balkh at that time.
The ancient city of Balkh, where Abu Ma’shar grew up, had once been an outpost of Hellenism in central Asia, and then had become a center for the mingling of Indians, Chinese, Scythians and Greco-Syrians with Iranians during the Sassanian period ...; its religious communities included Jews, Nestorians, Manichaeans, Buddhists and Hindus, as well as Zoroastrians. In the revolution of the middle of the eighth century, the people of Khurasan provided the Abbasids with their army, their general, and many of their intellectuals.
Like other intellectuals from Balkh, Abu Ma’shar – an expert in the hadith, or sayings of the Prophet – gravitated to Baghdad, probably at the beginning of the caliphate of al-Ma’mun. Then in 825, at the challenge of the great philosopher al-Kindi, Abu Ma’shar began studying mathematics, astronomy and astrology in order to understand philosophy. As David Pingree puts it, ‘In this effort he drew upon elements of the diverse intellectual traditions to which he was almost uniquely heir: upon the Pahlavi Greco-Indo-Iranian tradition in astrology, astronomy, and theurgy...’
Abu Ma’shar’s Zij al-hazarat was, according to Pingree, an attempt ‘to restore to mankind the true astronomy of the prophetic age’, which he sought to do by using Indian writings on the mean motions of the planets. Pingree gives this assessment of this and the many other works of Abu Ma’shar, who lived to be 99 years of age, or 102 according to the Islamic calendar.
In these writings...Abu Ma’shar did not display any startling powers of innovation. They are practical manuals intended for the instruction and training of astrologers. As such they exercised a profound effect on Muslim intellectual and social history and, through translation, on the intellectual and social history of western Europe and of Byzantium. Abu Ma’shar’s folly as a scientist has been justly pointed out by al-Biruni .... He is an interesting and instructive phenomenon, but is not to be ranked among the great scientists of Islam.
And thus science and philosophy came to Baghdad by many roads, ranging from Athens, Alexandria and Constantinople in the West to Khurasan in Central Asia and India in the East, drawn by the brilliance of the ‘Abbasid capital. Baghdad reached its prime during the reign of Harun al-Rashid, whose accession is described in the Thousand and One Nights.
And Harun, amid the pomp of his kingship, received oaths of obedience from the emirs, the notables and all the assembled people .... And all the provinces and lands of the Empire, and all the Islamic peoples, Arab and non-Arab, Turks and Daylamites, hailed the authority of the new Khalif and swore allegiance to him. And he began his reign in prosperity and magnificence, and sat shining in his new glory and in his power.