The House of Wisdom (19 page)

The politics of alchemy also played an important role in the rise of Western science, for requirements of state at times afforded its early practitioners invaluable protection against the condemnation of religion. In this way, it mirrored the development of astrology, which also had its many religious critics in both the East and the West. The princes of Europe were eager to bolster their flagging coffers by employing, in the words of one English monarch, “men learned in natural philosophy” to increase the royal holdings of gold coins through the practice of alchemy.
²⁴
In reality, the best the alchemists managed to do was devalue the crown’s currency through the stealthy introduction of impurities that swelled the number of coins but diluted their actual gold content. This technique was not unlike a modern paper-money economy’s simply printing new currency to cover its mounting expenditures. The forces of the church, who stood to lose power and influence at the hands of secular kingdoms so “enriched,” denounced the practitioners of these arts as charlatans. The popes and their allies also invoked church teachings to warn against interference by man in God’s natural order. “They promise that which they do not produce,” complained Pope John XII, in a papal bull of 1317.
²⁵

The earliest mention of
A Little Key to Drawing
is contained in a ninth-century library catalog from the Benedictine monastery on Reichenau, in Germany, but the lost manuscript to which it refers would have been older still.
²⁶
Clearly, European artisans had mastered and preserved some important industrial techniques throughout the turmoil of the early Middle Ages. This, however, did not blunt the enormous impact of the arrival of Arab alchemy and early chemistry beginning in the twelfth century, introduced by the likes of Adelard. Within a few short decades, his fellow Englishman Robert of Ketton produced the first full Latin text on the Arab art,
The Book of the Composition of Alchemy
. “Since what Alchemiya is, and what its composition is, your Latin world does not yet know, I will explain in the present book,” Robert promises his readers in the preface.
²⁷

Soon a flood of translated Arab alchemical works began to pervade the West, threatening to overturn Christendom’s traditional relationship between man and nature and prompting vigorous philosophical and theological debate about the use and abuse of technology.
²⁸
Spurred on by the arrival of these Arab teachings, the Latin alchemists were among the earliest pioneers in the West’s discovery of the natural world, while their theories of nature, such as that on the composition of matter, would contribute to the scientific revolution of the sixteenth and seventeenth centuries.
²⁹

Long before Adelard arrived in Antioch, ignorance, disorder, and self-imposed religious isolationism had cut the West off from centuries of scientific and philosophical advances. The natural world was largely unquestioned and unexplored, and early attempts to penetrate its mysteries often aroused suspicions of sorcery or the mischief of demons. With little or no grasp of physical laws that might explain the spread of deadly disease, for example, or illuminate the arts of navigation or telling time, medieval Christendom tended to see the universe as a dark and frightful place. Superstition ruled the day. In short, there was no method, only a sort of mania or madness—as witnessed by the widespread claim of apocalyptic visionaries on the popular imagination and extravagant explanations of natural phenomena. All that began to change with Adelard’s discovery of one of the greatest scientific works in history, the mathematical system of Euclidean geometry.

The thirteen books of Euclid, known as
Elements
, include six chapters on basic geometry, three on number theory, and a single section on “incommensurables”—what are known today as irrational numbers. The side and the diagonal of a square represent the most familiar example of incommensurable numbers. There is no single unit that can measure both lines; thus, their relationship cannot be written as a fraction or ratio. It has been suggested that the problem of incommensurables forced the Greek philosophers to discard the notion that the universe could be described fully in terms of positive whole numbers and to concentrate instead on developing geometry as a more accurate and useful representation of physical reality.
³⁰
The final three chapters of
Elements
are devoted to solid geometry.

Euclid’s own life and origins are obscure and subject to much speculation, although it is known that he founded a school in Alexandria, where he flourished around 300
B.C.
His masterwork represents a collection and reworking of much of Greek mathematics to date, presented in a compelling, logical format. Euclid begins by introducing the basic building blocks of geometry and then spells out a problem to be solved. Next, a proposed solution is presented. Finally, the
proof
reasons from the earlier propositions, or axioms, to establish the truth of the construction, and the
conclusion
confirms that the problem has been solved satisfactorily within the agreed rules of the game. Each successful demonstration forms part of the basis for later, more sophisticated problems.

Taken together, the thirteen books of
Elements
offer a comprehensive logical system and an introduction to deductive reasoning, essential to the development of the scientific method and rational philosophical inquiry. Yet medieval Europe knew almost nothing of Euclid’s science, except some poorly understood fragments preserved by Boethius and a few of the other Latin encyclopedists. Isidore of Seville, for example, devoted a total of just four pages of his
Etymologies
to the subjects of geometry, arithmetic, music, and astronomy combined.
³¹
Such scraps afforded Christian scholars no glimpse of the intellectual riches contained in Euclid’s
Elements
.

Euclid fared far better at the hands of the Arabs, who recognized his importance and made the mastery of
Elements
, along with the
Almagest
, the techniques of Hindu astronomy, and the natural philosophy of Aristotle, a cornerstone of their intellectual enterprise. It is worth noting that Arab scholars also identified the most serious shortcoming of the Euclidean system, the fifth postulate, which advances the notion that parallel lines can never intersect even as they extend to infinity. The essence of the problem lies with asserting the behavior of such lines outside human experience, and Euclid himself seems to have expressed some doubts about this aspect of his own work. All attempts to date to establish this rule as absolute have failed. However, the medieval Arab mathematicians repeatedly attacked the problem over the centuries in new and creative ways—work that eventually found its way to the West, where it later influenced a number of leading mathematicians.
³²

Caliph al-Mansur invoked Euclid’s teachings in the geometric design of his Round City, and his successors ensured that
Elements
was one of the first major Greek texts translated into Arabic. The works of two Abbasid scholars on
Elements
have survived to this day. The first scholar, al-Hajjaj, completed a full translation and an abridgment, the latter at the direct request of Caliph al-Mamun. A second, later version, one that more effectively tracks the Greek original, was edited and revised by Thabit ibn Qurra, the researcher at the caliph’s House of Wisdom whose
Book of Talismans
Adelard translated.
³³

The Arabs also produced dozens of commentaries on
Elements
and translated other important works by Euclid. Almost immediately, the Muslim approach to both science and philosophy began to reflect the Greek mathematician’s fundamental insistence on demonstrable proofs. This approach soon extended to questions of theology and religion, prompting the aristocratic scholar al-Kindi to seek out the teachings of Greek philosophers on metaphysics in order to subject matters of faith to this same form of rigorous analysis. Toward this end, al-Kindi commissioned Arabic translations of Greek philosophical texts that would one day pose a major challenge to the theologians of both the East and the West, including Aristotle’s works on cosmology and the soul.
³⁴

For medieval Europe, the discovery of the complete Euclid was a sensation. The three earliest Latin versions, based on the translation of al-Hajjaj three centuries earlier, have historically been attributed to Adelard.
³⁵
Editions by other scholars soon followed. Notations in a number of surviving manuscripts and the testimony of later medieval intellectuals establish Adelard’s close links to the earliest texts. Roger Bacon quotes from the third of these treatises—actually a commentary on Euclid rather than a translation—and refers to it approvingly as the “special edition of Adelard of Bath.”
³⁶
And there is no reason to doubt Adelard’s own account when he tells us in a later work that he already translated
Elements
some years before.
³⁷

No one has yet succeeded in unraveling the mystery of exactly which texts bear the master’s own hand. Still, Adelard’s fingerprints are all over the successful introduction of Euclidean geometry to the Latin world, as early as 1126. Whatever their exact provenance, these first manuscripts reveal much about the ways in which Adelard and the early Latin scholars who followed in his path assimilated and gradually mastered Arabic scientific texts. The oldest editions bear all the hallmarks of an early, tentative encounter with the
studia Arabum
. The translation of technical terms is often inconsistent and relies heavily on imprecise or erroneous Latin terms; at other times, failing to find any Latin equivalent, the author simply transliterates from the original Arabic. Such linguistic poverty was soon to plague the translations of Muslim philosophy as well; one early version of a major work of Arab metaphysics is forced to fall back on a single Latin word,
esse
, to represent thirty-four distinct Arabic expressions for being and related notions.
³⁸

According to a modern linguistic analysis, the earliest translation relies on more than seventy direct transliterations from the Arabic in order to present basic geometric concepts for which medieval Latin had no ready terminology. These include
diameter, tangent
, and
ratio
. However, a slightly later version has reduced its reliance on Arabic to fewer than two dozen transliterations and has replaced all of the terms above with suitable Latin equivalents. This suggests that Adelard—or perhaps a colleague or one of his pupils—had since made considerable strides in mastering the material at hand and identifying or producing Latin variants.
³⁹
Some of the extant Euclid manuscripts also include marginal notations discussing Arabic vocabulary or explaining points of grammar, a technique that Adelard himself used in other works—in one, he highlights the foreign words in special red ink—and one that was carried on by his students.
⁴⁰

Virtually all surviving examples of the second of the three early Latin Euclids explicitly identify the work as that of Adelard. This version proved a “bestseller” for five centuries and formed one of the centerpieces of the West’s emerging new sciences. At least fifty-six manuscripts have survived, a relatively large figure that attests to the work’s general appeal and widespread use.
⁴¹
It served as the basis for what later became the definitive scholarly text of the day and was cited widely in commentaries throughout the thirteenth and fourteenth centuries. In the realm of theory, Euclid gave the Latins their first explicit model of scientific thinking and exposed them to the classical approach to logical deduction.
⁴²
In practical terms, his geometry was crucial to the development of medieval astronomy, for it allowed the measurement of far-off celestial bodies in terms of angles and degrees and helped explain and predict their movements through the heavens.

These first Latin translations, which sought to interpret Euclid for a Western audience, set the stage for the rigorous Arabic program of study that culminated in mathematical astronomy and applied astrology.
⁴³
They also had a profound effect on the overall development of early European scientific and philosophical thinking. Robert Grosseteste—literally “the big-headed,” prompting one contemporary to call him “Robert of the big head but subtle intellect”
⁴⁴
—recognized the fundamental importance of the new geometry. “The utility of a consideration of lines, angles and figures is the very greatest, since it is impossible that natural philosophy be known without them. They obtain absolutely in the whole universe and in its parts,” writes Robert, an early chancellor at Oxford, who died in 1253. Without lines, angles, and figures, he notes, it would be impossible to know the true nature of things.
⁴⁵

Roger Bacon, Robert’s younger colleague, repeatedly invokes Adelard’s special edition of Euclid as an authority for the idea, just beginning to take root in the West, of the uses of proof in both logic and the theory of knowledge, or epistemology. Roger draws explicitly on Adelard for his own groundbreaking work on theories of vision and on the broader question of the role of experimentation in science. “An axiom, as Adelard of Bath says in his edition, is interpreted as a dignity, for it explicates the definitions of things. And this is especially true when the axiom is taken strictly, although in a wide sense all principles are called axioms, as Adelard of Bath’s epilogue at the end of the book supposes,” Roger writes in his
Geometrica Speculativa
.

He then goes on to link Adelard directly to Aristotle’s own work on experience and experimentation, before adding, “A postulate is, as Adelard of Bath says, that which being conceded nothing inconvenient follows from the hypothesis.” The union of these three elements—geometry; the system of axioms, postulates, and proofs explained by Adelard; and direct experience—formed the basis for much productive Western research and scholarship, including the development at Oxford of calculus and formal analysis.
⁴⁶
The new art of geometry was also central to medieval philosophical investigation into light, color, and vision.