The House of Wisdom

by Jonathan Lyons

  Much of al-Khwarizmi’s intellectual inspiration derived initially from Indian science. The bulk of his astronomy relies on Hindu tradition and, to a lesser extent, Persian teachings. The Indian city of Arin, for example, is used in the zij al~Sindhind as the reference point for astronomical measurements, much as the meridian at Greenwich, England, is used today. One version of the zij calls Arin the “center of the sphere of the earth.”66 Methods for the determination of the moon’s motion and for measuring the true longitude of a planet betray the work’s strong Hindu roots.67 Al-Khwarizmi devotes the beginning section of his text to conversions between the different calendar systems of the ancient and contemporary world—Arab, Christian, Egyptian, and Persian—and he takes June 16, 632, the beginning of the reign of the last Persian king before the Muslim conquest, as his starting point, or epoch.

  Nonetheless, there are already scattered hints at the growing influence of Greek learning on the Arab sciences contained in the zij al~Sindhind and in his other works, particularly the algebra text. This is hardly surprising. Al-Khwarizmi’s patron, al-Mamun, presided over the beginning of a turn among the majority of Arab scholars away from early Hindu and Iranian traditions in the hard sciences and toward those of Greece and Hellenistic Egypt. The centerpiece of this flurry of scientific activity under al-Mamun was the translation of Ptolemy’s masterwork of classical Greek astronomy, the single most important book among medieval Arab scholars, after the Koran. Ptolemy was born around 100 A.D. and spent his working life in Alexandria, then the center of Greek learning and home to the world’s greatest library, forerunner of Baghdad’s own House of Wisdom.

  There he produced invaluable works on geography and astrology, among other topics, but none was as vital as the book known among the Greeks as the Megale Syntaxis, or “the great composition,” but later recognized universally by the Arabic corruption of its name, the Almagest. Ptolemy’s text presents an elaborate and all-encompassing theory of the movement of the fixed stars, the sun, the moon, and the five visible planets—Mercury, Venus, Mars, Jupiter, and Saturn—one that would hold up until the mid-sixteenth century. In terms of Greek science, Ptolemy so dominated the field of astronomy that the works of his most important predecessors virtually disappeared.68 In the West, which would learn of Ptolemy much later through its encounter with Muslim science, he became a mythic, almost mystical, figure often confused with those heirs to Alexander the Great, the Ptolemaic kings of Egypt; medieval images commonly featured the famous astronomer with a crown on his head.

  But for the Arabs, the Almagest provided a priceless road map for research and study, so much so that it was subject to periodic retranslation, revision, and commentary by the leading scholars of the House of Wisdom throughout the ninth century and beyond. Al-Mamun’s innovative program of astronomical observations at Baghdad and Damascus, for example, was designed to test the results of the Almagest and compare them with its own. The star tables that resulted from these experiments eventually superseded those grounded in Hindu science, notably al-Khwarizmi’s zij al~Sindhind. The caliph’s geodetic survey on the hot, dusty plain of Sinjar likewise was motivated by questions culled from a careful reading of the Almagest. These and other experiments yielded results that often improved significantly on the data provided by Ptolemy—who was notorious for making relatively few observations of his own and instead relying on the earlier observational work of others. Yet there was no immediate sign that such shortcomings in the master’s work dismayed or shocked the Arabs or prompted doubts about the reliability of the general theories presented in the Almagest.69 That would come later, after Arab science and philosophy had matured over the course of several centuries.

  The royal endorsement of Greek learning may have had almost as much to do with contemporary politics and diplomacy as with intellectual taste or scholarly analysis. The death in 809 of al-Mamun’s father, al-Rashid, sparked a civil war among the Abbasids, and al-Mamun was able to secure power only after a long period of bloody struggle with the forces of his half brother al-Amin. Badly weakened by this war of succession and his own prolonged absence from the capital, al-Mamun took up residence in the Round City determined to centralize political and religious authority in his own hands.

  This ruthless consolidation of power was accompanied by a new aggressive tone in the caliph’s foreign policy, one that recast the traditional geopolitical rivalry with the adjacent Byzantine Empire in the stark terms of religious struggle. Even here, state intellectual policy came to the fore: In the new Abbasid view, not only were the Eastern Orthodox Byzantines infidels, but they were also guilty of rejecting classical Greek learning after the coming of Christianity. The religious superiority of Islam was augmented by the fact that the Muslims had had the good sense to recognize the genius of ancient Greece. To oppose the Byzantines was to be in favor of Greek learning, and vice versa.70 Earlier Byzantine harassment of the Nestorian, Syrian, and other eastern Christian scholars, many now taking refuge among the Muslims, appeared to bear out this new propaganda. Al-Mamun was also a supporter of a radical rationalist reading of Islam, a position that appeared to mesh easily with renewed interest in Greek philosophical studies.

  Yaqub ibn Ishaq al-Kindi, celebrated as the Philosopher of the Arabs, soon took up the anti-Byzantine refrain. He posited a mythical past in which the ancient forerunners of the Greeks and the Arabs were represented as siblings. It was only natural, al-Kindi suggested, that the Arabs inherit and build upon the earlier work of their brothers, the pre-Christian Greeks, a view that became increasingly entrenched in the Muslim world.71 One century later, the geographer al-Masudi made the link between the arrival of Christianity and the decline of learning explicit: “During the time of the ancient Greeks, and for a little while during the … [Roman] empire, the philosophical sciences kept growing and developing, and scholars and philosophers were respected and honored. They developed their theories on natural science—on the body, the intellect, the soul—and on the quadrivium … The sciences continued to be in great demand and intensely cultivated until the religion of Christianity appeared among the Byzantines; then they effaced the signs of philosophy, eliminated its traces, destroyed its paths, and they changed and corrupted what the ancient Greeks had set forth in clear expositions.”72

  The policy of fostering scientific and philosophical activity, research, and innovation addressed the vital political, religious, and diplomatic interests of the early Abbasid state. But one industrious chronicler of medieval Arab intellectual history preferred another explanation, ascribing al-Mamun’s passion for the work of the House of Wisdom to a mystical dream. According to Ibn al-Nadim, the sleeping caliph spotted a bald, light-skinned Aristotle sitting on his bed. Overcoming his initial shock at finding himself face-to-face with the great philosopher, al-Mamun asked him to define “that which is good.” Aristotle replied that reason and revelation—that is, science and religion—were both good and in the public interest, a response the caliph took as confirmation that scientific scholarship was a religious duty. “The dream,” Ibn al-Nadim concludes, “was one of the most definite reasons for the output of books.”73

  Chapter Four

  MAPPING THE WORLD

  AL-MAMUN’S GREAT Abbasid Empire owed much of its enormous vitality to the spiritual and intellectual energies unleashed two hundred years earlier in a remote corner of the Arabian Peninsula. There, in 610, a former caravan driver and small-time merchant began to receive revelations from God during periodic retreats in the nearby mountains. After receiving his initial revelations, Muhammad was troubled and at first told no one, except his beloved wife Khadija. But he was soon commanded by God to make his message public: “O you enveloped in your cloak, arise and warn (Koran, 74:1–2).”1

  Muhammad’s message of social justice, the need for good works, and the oneness of God attracted some members of Mecca’s elite, such as Khadija, herself a wealthy business owner. And it resonated with members of the lesser Arab tribes and the urban poor in his nati
ve city of Mecca. But it also drew the anger of many among Mecca’s powerful merchant class, grown fat on their command of valuable trade routes and their monopoly over lucrative religious tourism to the city’s cube-shaped Kaaba shrine, then a center of traditional idol worship.

  In recent decades, the rise of these same wealthy tribes had largely displaced the old order in and around Mecca, reducing the standing and power of Muhammad’s own clan, the Banu Hashim, and others like it. In keeping with the Arab tradition of collective clan responsibility, Mecca’s oligarchs pressured the Banu Hashim elders to rein in Muhammad before he could destabilize the entire economic and social order. His opponents imposed a boycott against anyone who supported the firebrand preacher. Muhammad found himself the subject of taunts, insults, even an assassination attempt. Loudmouthed cynics demanded that he produce a miracle in support of his revelations. In the face of such pressure, recruitment of new followers tailed off sharply. With the death of his uncle Abu Talib, Muhammad lost the protection of the leading voice among the Banu Hashim. Life in Mecca was no longer tenable.

  The result was the emigration, called the bijra, in 622 of Muhammad and a small band of followers north to the oasis town of Medina, an event that would prove so momentous that it was later taken as the starting point for the Islamic calendar and thus for all of Muslim history. Muhammad had cut a deal with Medina’s fractious Arab tribes, mostly pagans but also several important Jewish clans: He would arbitrate their interminable disputes in exchange for protection for himself and his supporters against the merchants of Mecca. Once Muhammad was secure in this new base, his relationship to the young community of believers around him and the content of his preaching began to change dramatically.

  Revelations from the Meccan era, recorded among the 114 chapters of the Koran, are largely in the age-old Near Eastern tradition of spiritual warning. They were revealed to Muhammad over the course of more than two decades and consist of brief messages, generally in rhymed prose, calling on humanity to mend its ways and please the one true God before Judgment Day. For their part, the Holy Book’s Medina sections, longer and more detailed, generally reflect more quotidian concerns. They also provide specific guidelines for ordering the political, social, and economic affairs of Muhammad’s growing number of followers.2 Only now is he portrayed as the messenger of God, the last of the line of divine prophets that includes Abraham, Moses, and Jesus.3

  There is every indication that Muhammad had high hopes that his preaching would find favor among Medina’s Jews, less powerful than they once were but still important players in the political and economic life of the town. After all, Muhammad must have reckoned, his central message of strict monotheism augmented that which had already been spelled out to the Jews by their prophet, Moses; surely the influential tribes of Medina would recognize that and once again conform their behavior, which had drifted badly over the years, to the word of God.4 The period immediately surrounding the hijra saw a number of attempts by Muhammad to woo Jewish support. These included recognition of the Jewish Sabbath, fasting on the traditional Day of Atonement, general alignment with Jewish dietary laws, and the practice of intermarriage. Some have found suggestions in the Koran that Muhammad may have at one point considered a sort of federation linked by shared religious precepts.5 “Say: O People of the Scripture! Come to an agreement between us and you: that we shall worship none but God … and that we shall ascribe no partner unto Him, and that none of us shall take others for lords beside God” (3:64).

  Perhaps the most public expression of Muhammad’s early policy toward the Jews was the decision shortly after his arrival in Medina to adopt the Jewish notion of rectiting daily prayers in a specific direction, known in Arabic as the qibla. Facing Jerusalem during prayer was an established tradition among the Jews. The Bible recalls that King Solomon built the First Temple in Jerusalem and then declared that the Jews would henceforth “pray to the Lord in the direction of the city which You have chosen, and in the direction of the House which I built in Your name” (I Kings, 8:44). Solomon’s promise became incorporated into Jewish law, and early synagogues were generally constructed in accordance with this dictate.

  Any hopes Muhammad may have had for mass support among the Jews of Medina proved unfounded. It soon became clear that the leading Jewish tribes were not prepared to accept his teachings. Nor would they recognize him as a true prophet. In response, the Muslim leader began to step up political pressure on the Jews, while the later revelations collected in the Koran sharpened the intellectual and theological challenge to Judaism. In particular, the Jews were reproached for worshipping the golden calf, a throwback to impermissible idol worship, and for developing a legal code outside the strict confines of biblical teachings. As Islam first began to emerge as a faith in its own right, it adopted a month of fasting, as distinct from the single day set aside by the Jews. To distinguish his message from earlier revelations, Muhammad began to stress his spiritual ties to Abraham, who preceded the Jewish and Christian prophets. Abraham, the Muslims now taught, founded the sanctuary at Mecca, the Kaaba, and prayed for a prophet from the ranks of the city dwellers there.6 Sealing his break with the Jews, Muhammad abandoned their traditional Jerusalem-facing qibla for that of the Kaaba. According to some early Muslims, he did so while leading communal prayers by turning abruptly toward Mecca, at a place known ever since as the Mosque of the Two Qiblas.7

  The notion of sacred geography, measured less by the cartographer’s coordinates than by spiritual need or scriptural reading, has long flourished in the human imagination. Its contours are shaped by religious experience grafted to common understandings of time and space, rather than by the physical features of the earth or the shifting political boundaries of city, state, or nation. The pilgrimage site, the scene of miracles, or the setting of another holy event—all may define the topography of the sacred map. Perhaps nowhere has this idea proved more compelling than in the Near East, birthplace of the three major monotheistic faiths. Here, geographies sacred and profane intersect in the ritual of prayer and in competing claims on holy space, as believers seek to align themselves physically with the divine.

  Among the Muslims, the precise direction of prayer took on great religious, cultural, and political importance. As a result, Islam has historically gone to considerable lengths to define and determine the qibla and to honor the sacred geography centered on the qibla’s terminus at the ancient Kaaba—timeless symbol of God’s power and presence. In addition to the daily devotions, accurate knowledge of the qibla is required for the ritual slaughter of animals for food, the burial of the dead, and the call to prayer. The location of Mecca is, of course, also crucial for the hajj, the once-in-a-lifetime pilgrimage, which is a religious obligation for any able-bodied Muslim who can afford the trip. Over time, a huge theological and scholarly enterprise grew up around the observation of Islam’s sacred geography in general and the qibla in particular.

  Today, many tend to see religion as the enemy of scientific progress. Yet early Islam openly encouraged and nurtured intellectual inquiry of all kinds. Muhammad once said of the pursuit of knowledge, “Seek for science, even in China.” Another of the many sayings attributed to the Prophet, carefully collected, collated, and studied down through the centuries and known as the hadith, celebrates scholars as the true “heirs to the prophets.” The hajj, meanwhile, ensured the annual gathering of Muslims from all over, creating a global marketplace of ideas, innovation, learning, and cultural exchange.

  Arab scientists and philosophers readily found divine support for science in the revealed word of God. A number of verses in the Koran refer to the order inherent in God’s universe and to man’s capacity to recognize and exploit this order for his own needs, such as keeping time: “He [God] it is who appointed the sun a splendor and the moon a light, and measured for her stages, that you might know the number of the years, and the reckoning [of time] … He details the revelations for people who have knowledge” (10:6). Elsewhere, the Holy Book adv
ocates the use of elements of God’s creation for orientation amid the featureless deserts and navigation across the vast oceans: “He has appointed the night for stillness, and the sun and the moon for reckoning … And He it is Who has set for you the stars that you may guide your course by them amid the darkness of the land and the sea” (6:97–98).

  At the same time, many of Islam’s rituals and obligations as laid out by the Prophet demanded a relatively sophisticated understanding of the natural world. Believers could not simply follow the advice of the Christian philosopher St. Augustine and allow piety to close their eyes “to the course of the stars.” Rather, Muslims must know the proper times of the five daily prayers, the direction of Mecca, and the start of the lunar fasting month of Ramadan. “Knowing the prayer times is a prescribed duty for discerning Muslims. This is summarized in the Koran, my friend, and was explained by [the Prophet Muhammad] … There is no virtue in a person who is neglectful of the prayer times, and he has no knowledge of Him who is to be worshipped,” writes the medieval astronomer Ibn Yunis.8