EUROPE’S INTELLECTUAL REAWAKENING

If not for these great Islamic scholars and their numerous colleagues, the Western intellectual world would look very different today. As previously noted, early Christian Europeans regarded the pagan Greek and Roman manuscripts with hostility and suspicion. Left to them, the great classical works would have been deliberately destroyed or allowed to disintegrate and disappear. Inevitably, however, by the year 1000 there was increasing contact between the Christian and Islamic worlds. Although at first this contact was hostile during the Crusades, things gradually became more peaceful and civilized.

Trade was one such peaceful enterprise, and in the late 1100s a young Italian named Leonardo Fibonacci (ca. 1170–1240) frequently accompanied his wealthy merchant father on trips to north Africa. Interested in keeping accounts, he learned about Al-Kindi’s system of Indo-Arabic numerals, and in 1202 wrote a book in Latin, Liber Abaci (Book of Calculation) describing its uses and virtues. These included not just practical arithmetical operations, but also several engaging problems in algebra and an important contribution to number theory: He described a fascinating series of numbers, now named after him as the Fibonacci sequence, in which each new number is the sum of the two that preceded it: 1 (0+1), 2 (1+1), 3 (2+1), 5 (3+2), 8 (5+3), 13 (8+5), 21 (13+8), and so on.

This sequence has many interesting features, including the fact that as the sequence progresses, the ratio between each number and the one that follows comes ever closer to a value that has come to be known as the golden ratio. Therefore, 1/2 = .500; 2/3 = .667; 3/5 = .600; 5/8 = .625; 8/13 = .6154; 13/21 = .61905, and so on, as each decimal fraction closes in on, but never quite reaches, a proportion of .6180339887 . . . carried on to indefinitely many decimal places. The proportion represented by this irrational number (i.e., one that can never be completely represented by a complete numerical fraction, like the famous pi) has proven to have central significance in geometry, patterns of organic growth, and aesthetics. Fibonacci’s book was an immediate hit with European scholars, and established number-based mathematics as a major field of study.

Some peaceful mixing of cultures also took place at locations on or near the borders of Christian and Islamic territories, such as Sicily and, especially, the southern half of Spain. The small but cosmopolitan city of Toledo in central Spain became a particular center for the mingling of Christian, Islamic, and Jewish populations. During the early 1100s, a flourishing “school of translators” arose: Arabic-speaking Christians who translated the great Arabic texts (including their translations of the original Greek classics) into Latin.

An educated Christian class had been growing in other parts of Europe, concentrated first in monasteries and then in church-related and explicitly scholarly institutions they called “universities.” The first university was established in Bologna, Italy, in 1088, followed by others in Paris, Oxford, and Modena in the following century, and a host of other cities soon afterwards. Besides offering training in medicine and law, the universities also became forums for the analysis, discussion, and debate over scholarly works—and their practitioners became known as scholastics or “schoolmen.” At first their studies focused on theological and other sacred writings in the Judeo-Christian tradition, but gradually the translations from the Arabic emanating from Toledo and elsewhere became part of their curriculum.

Although aspects of the classical works at first seemed shocking, the Islamic commentators had gone out of their way to show how the major ideas could be harmonized with their own monotheistic faith. Soon enough the scholastics came to a similar conclusion. Plato’s notion of a world of perfect and ideal forms, perceived only indistinctly by imperfect but potentially immortal souls, could be equated with heaven as the goal for repentant sinners. Aristotle came to be particularly esteemed by the great scholastic theologian Thomas Aquinas (1225–1274; he was elevated to sainthood in 1323). Aristotle’s idea of a purposeful unmoved mover as creator of the universe could be equated with the Christian God, and Avicenna’s conception of the Aristotelian soul could be compatible with both monotheism and, in its rational component, immortality. Immensely influential, Aquinas referred to Aristotle as “the Philosopher,” and established Aristotelianism as an intrinsic part of medieval Christian doctrines.

The European rediscovery of Democritus and atomic theory would take longer. An Italian book lover and scribe (someone who produced handwritten copies of manuscripts) came upon the only surviving copy of Lucretius’s poem in an obscure monastery in 1417. Recognizing its uniqueness and beauty, he produced and oversaw the production and distribution of copies. As a result, the atomic theory was introduced into Western Europe. Initially greeted with shock and outrage for its apparently materialistic and atheistic implications, its conception of tiny and interacting material particles as the fundamental elements of the physical universe gradually and increasingly attracted the attention of serious scientific thinkers.*

Among the most important of the modern thinkers was the Frenchman René Descartes. Trained in classical doctrines, with further appreciation of the Islamic contributions to mathematics and science, and knowledge of the general atomic model, he reformulated the Aristotelian psyche in a way that provided essential foundations for an eventual science of psychology. Descartes and two of his most important successors are the main pioneers covered in the next chapter.