To say that Spain was a natural bridge, linking the East and the West and thus enabling the rebirth of sciences which led to the Renaissance, could be considered today a tired platitude usually taken as little more than a geographical fact. However, not much attention has been paid to understanding how such a momentous development came forth within the framework of the particular history and socio-cultural milieu of the Iberian peninsula. One must begin by acknowledging how difficult this development was, given the depth of the Augustinian view of man as an overly spiritual phenomenon, fully absorbed into the Creator of the nerse upon his final return as homo viator.¹ Let me say (to save words and time) that such a commitment to the supernatural implied the demise of nature, conceived as the non-being of matter. We only need to look at the visual arts and the representation of the human body (usually Adam and Eve naked in Paradise) to understand the extent to which nature no longer existed. Even painters seemed to have lost their eyes in a literal sense and, unable to see external reality as it was, they only tried to represent it with symbols. The very idea of knowledge had turned to the theological sphere, and any attention paid to anything else was deemed not so much a heresy as simply a waste of time and effort. Theology and science had parted ways, and to this very day they do not make good bedfellows.

Medieval science could only come into being as a relay from ancient Greece, since the Romans (full-time lawyers that they were) did not act as more than its occasional clients.² Saint Isidore in Spain, Bede in England and Marcianus Capella in Africa tried to salvage as many shreds of Graeco-Roman science as they could, but they did it in a haphazard, elementary way, leading to a dead end and not to a perennial light for the Christian West. Modern scholars took too long to understand that the mere notion of philosophia naturalis had to come from outside the Western world. The Arabs were also committed to revealed monotheism, but not to the Judaeo-Christian doctrines of original sin, the evilness of sex and religious hierarchy. They shared the eschatology of the souls, but not the rejection of human knowledge. When the Arabs conquered Alexandria, they came to rule a substantial part of the moribund Hellenistic world, and they did not hesitate in appropriating any kind of knowledge that could help them fill the holes of their own pre-Islamic culture.

Put that way, it seems only a plain and sensible course of action, but we must keep in mind that such an attitude was due by the Koranic doctrine of protection (dhimma) of the Abrahamic religions or people of the Book (ahl al-kitab),Reference Makki³ and that it was of the essence where it mattered most; that is, in the former Byzantine provinces of the Near East. Christians, largely Nestorian and Monophysites in the Syrian-Lebanese area, had been harshly treated by the Constantinoplan Patriarchate and received the Arabs as liberators, setting the stage for the kind of work that made possible the rebirth of Greek science, first in Baghdad and later in Toledo. What we have in both cases was a multicultural approach to a task shared among men of different origins and religions, initially under Muslim rulers, and then under the unique but basically similar mudéjar atmosphere of medieval Spain. It was the formula under which Nestorians, raised in Greek culture, were instrumental in the fast transformation of Syriac and Arabic into the new role of scientific languages. The golden key of it all was the work of translation, which began as a way to satisfy a down-to-earth need, initially in the field of Medicine, and reached its moment of splendor in the seventh and eighth centuries under the first Abbasid caliphs. It was the second caliph, Al-Mansur (754–775), who sponsored the great Hunayn ibn Ishaq (the Latin Joanitius), a team leader of Syrio-Byzantine scholars working at Baghdad’s bayt al-hikma or ‘House of Learning’Reference Balty-Guesdon⁴ that allowed the Arabs to catch up with Greek science in record time, and provided a future model for the transmission of knowledge from Spain to the West. We are lucky to have a definite landmark for the transfer of Greek learning to Muslim Spain in particular: the gift of the work of Discorides from the Byzantine emperor Constantine VII Porfirogenetos (905–961) to the Umayad caliph Abd al Rahman III (912–961), immediately translated into Latin by a Greek monk and his helpers in Córdoba.Reference Millás Vallicrosa⁵

We should understand that for the Christian West, the dereliction of science was due more to indifference than to animosity. The Church never issued a formal condemnation of science,Reference Lindberg⁶ and it was saint Augustine himself who invoked the spoliare Aegyptios as a Biblical sanction to raid the learning of infidels. Through the high Middle Ages, monastic life faced very definite needs in the fields of arithmetic and astronomy for records, time-keeping, and liturgy.Reference McCluskey⁷ By the end of the 10th century the Catalan monastery of Ripoll had amassed a sizable library of translations, due to the presence of Mozarab monks assimilated to Arab language and culture. Astronomy was already well-established in al-Andalus, with Abul Qasim Maslama and his school by the early 11th century, and in the second half of that same century the city of Toledo could boast the names of Ibn Said and the great al-Zarqali,Reference Millás Vallicrosa⁸ known in the West as Azarquiel.

It is also a platitude to dwell on the importance of the pilgrimage to Saint James of Compostela as a link of faith mutually beneficial for both Spain and Europe. It is far less known that the Iberian peninsula saw, at the same time, another kind of pilgrimage, not religious but scientific, not a movement of masses, but a trickle of ambitious minds.⁹ In the year 964, the Catalan monastery of Ripoll received its first famous guest, the monk Gerbert of Aurillac,Reference Flusche¹⁰ who then went to Córdoba and became upon his return a beacon of learning on the strength of the translations that he took with him to Rheims. Admired as a living myth, he became pope Sylvester II (999–1003) and, as such, the center of a two-edged legend, cast as either a prodigy of learning or, one may choose, as an evil magician.

Spain assumed for the future a clear role as scientific purveyor, and Gerbert’s visit was returned by Petrus Alfonsus (1062–1130), a former rabbi who, fired by missionary zeal, went to England as physician to Henry I, preached the Gospel of Astronomy and, by instructing Walcher of Malvern and Adelard of Bath, ushered in Britain’s permanent love affair with science.¹¹ By the end of the 11th century, Spain was already established as the Western fountainhead of translations and, after the fall of Toledo in 1086, it became the undisputed European center of scientific learning. The capital of the most successful of Arab taifa or petty Arab kingdoms (muluk al-tawaif), it looked to the glories of Córdoba during the Umayyad Caliphate, just as that city had looked to Abbasid Baghdad. After the conquest, king Alfonso VI of Castile took pains to keep the city intact and, above all, to retain its Muslim population under a pact of respect towards their Islamic identity. This situation is the reversal of a previous one: Muslims are now the dhimmi and it is the Christians who try to catch up with their learning. The Toledo that was now attracting the iuventus mundi has been described as ‘a city of freedoms’,¹² a magnet to Jews ousted by the African Almoravids, as well as to Italian and French traders. For more than a century Toledo basically remained Arabophone, with the Castilian vernacular serving as the language of communication between its three communities, and with Latin confined initially little more than a handful of French monks in its Cathedral.

Toledan Jews and Mozarabs could easily translate from Arabic into Castilian, a key language vested with the same role that Syriac or Aramaic had played three centuries before in the East. The final product came from the hands of another translator, usually a foreign clerk who knew both Latin and Castilian, but no Arabic. The Latin text was, in fact, the fruit of a transaction set on transmitting the inner meaning, much beyond the capacity of the word-by-word translation that had failed in other places. Besides heavily committed patrons, the immense work being carried out at Toledo required strong and diversified infrastructures of support, beginning with the well-stocked libraries of the taifa Moorish rulers, as well as the scouts sent to the still Islamic al-Andalus to look for new finds, something to which Muslim fanatics were heartily opposed.Reference Lévi-Provençal¹³ The fact that the works of Averroes and Maimonides were soon translated in Toledo shows that the city was still a living part of the same intellectual sphere.

From the first moment, the focus of it all was a fascination with astronomy, considered the highest achievement open to the human mind. Its attainment was worth any human sacrifice, made one’s name revered, and turned the Almagestum Reference Toomer¹⁴ into the Holy Grail of the Ptolemaic universe. Incorporated in the quadrivium, Astronomy was indistinguishable from astrology and mathematics. The former, moreover, was prized as the link between the macrocosm and the microcosm, and was deemed responsible for the connection of celestial bodies with everything human, including health, politics, marriages and births.Reference Vernet¹⁵ John of Seville¹⁶ built his reputation on his translation of Abu Ma’shar, the Master of Baghdadi astrology in the ninth centuryReference Carmody¹⁷ and Alfonso of Castile was first known in Europe as ‘the Astrologer’. His very personal interest in astronomyReference Gingerich¹⁸ was by no means entirely Platonic: better astronomical tables amounted to more accurate judiciary predictions, helping to lay the foundations of what we could call a scientific approach to politics.Reference Vernet¹⁹ From the days of Ripoll, we could in all justice define this mindset as the culture of the almost sacred astrolabe,Reference Viladrich and Martí²⁰ introduced to the West from Ripoll by Gerbert, and the name chosen by Abelard and Eloise for their son.

It is easy to understand that a visit to Castile could be a transforming experience, as it was for the last great abbot of Cluny, Peter the Venerable in 1142.Reference Kritzeck²¹ It was there that, to his amazement, he learned that Islam was a monotheistic Abrahamic religion, and that he hastened to become the patron of the first translation into Latin of the Koran and of other materials, known as Collectio Toletana, which became the foundation of medieval Islamology.Reference Monneret de Villard²² Modern scholarship was rather slow in realizing that from the beginning the Arabs were not servile followers²³ and that the translations were only the mainstay of a vast, fully-fledged, many-sided effort at scientific advancement which extended itself to instruction, libraries, zoos, botanical gardens, lexicons, and observatories. Toledo, though it never knew any formal ‘school’ of translators,Reference Lemay²⁴ still came to be for the sciences what Paris was for theology and Bologna for law. It was a place to study, and from which it was possible to return with a load of books in Latin translation that would suffice for a lifetime of study. In other words, Toledo was home to many undeclared schools, where Graeco-Arab Science was taught privately by Jews and Mozarabs. The same arrangement existed in al-Andalus for the teaching of ‘foreign’ (i.e. non-religious) sciences, after zealots became suspicious of the falasifa, and excluded them from the ‘madrasas’. Masters quietly, and in their own homes, taught philosophy and the natural sciences to a small circle of students,Reference Marín²⁵ and in spite of the Islamic intransigence of the African Almoravids and Almohads, they were successful to the point that those schools, called madhab,²⁶ educated Maimonides and Averroes and later, in the reconquered Balearic islands, Ramon Llull.

The Spanish Church at the same time was uninterested in any kind of higher learning and simply did not care about the licentia docendi which elsewhere remained under its strict control. Knowledge of Latin among the clergy had fallen to abysmal levels, and those very few that were reasonably educated had studied in France or Italy. For a long time, Spanish scholars have therefore faced a vexing question: the Latin translations made in Toledo seemed aimed to satisfy a foreign demand, and only had a faint echo in Spain itself.²⁷ We are now beginning to understand that one of the facets of the Toledan phenomenon was its rather unique language situation. Instruction could not be conducted in Arabic, inaccessible to most pupils, or in Latin, unknown to Jews and most Mozarab teachers. The problem could only be bridged by the Castilian vernacular, which began to be known abroad as lingua Tholetana and could easily be learned by anyone already schooled in Latin. The system duplicated in part the one used in the translations, but it was the result of the crisis of Latin in the Iberian peninsula, where even the clergy as a whole could not manage the language properly. By the second third of the 13th century, Spain was so disengaged from Latin that churchmen in Castile even had trouble understanding the directives that came from Rome.Reference Linehan²⁸ As a result, the idea of higher learning was no longer embodied, as elsewhere, by the clergy, but by Moors and Jews as undisputed masters of astronomy-astrology, medicine, and natural sciences – that is the Arabic hakim to be precise.Reference Nasr²⁹

The bulk of the translation effort detached itself from Latin, giving way to the very unusual case of a vernacular used from its initial period as a language of culture and all of this in a high tide of activity linked to Toledo, and also to Seville and Murcia under Alfonso X, the Learned King (1221–1284). Castile had become a great Christian power, but it was still a poor relative of Medio-Latin culture, and all the great medieval rulers knew that collective ignorance was tantamount to political weakness. Following the example of Charlemagne, it became a dogma that raising the level of learning was synonymous with a better educated clergy. It is what Alfred the Great and Henry II of England and Saint Louis of France tried to do. It was also the recipe adopted in Spain by Fernando I and his son Alfonso VI, to the point of submitting 11th-century Castile to ecclesiastical colonization by the French Cluniac monks, who knew at least some decent Latin. After their complete failure, the Learned King threw in the towel as far as Latin was concerned, and, hastening a development which in the rest of Europe would take several centuries, went fully over to Castilian. Turning his back on the problem with Latin, Alfonso X tried to set up the tools of an advanced culture for the benefit not of a privileged group, but of a whole people. He did so with the precocious national design of empowering his subjects through the use of the vernacular in law, history and, first and foremost, astronomy and the sciences. Thus, Alfonso X repeated what Caliphs such as al-Mansur and al-Hakan II had done in Baghdad and Córdoba, respectively. Alfonso’s personal involvement, however, went much beyond patronage. He directly managed the project, made technical decisions, and even bothered to check the language itself of the translations. The Learned King clearly embodied a concept of royalty of long Solomonic roots, but advanced again in the 12th century by Maimonides and Averroes; i.e. the sovereign as the supreme teacher of his people, well-versed in every kind of natural knowledge and exercising his rule under the purview of an educational structure.

Alfonso’s immense scientific project ignored theology and metaphysics, but took a strong interest in the underpinnings of Islam and Judaism, and tried to cover what he called el saber de las naturas (the sciences of nature) including, besides his much admired Tablas Alfonsíes, alchemy, clock-making, optics, automatons, the veterinary sciences, agriculture, and everything else; but (surprisingly) not medicine, in recognition of the latter’s status as the privative domain of Spanish Jewry. Another lost province of science was erotology, faint echoes of which are still discernible in the Lapidario-Libro de las formas, the only item in Alfonso’s vast scientific corpus that continues to appeal to modern readers.Reference Villanueva³⁰ And, of course, it was all magic. Convinced, as were the most brilliant minds of his time, of magic’s rationality, Alfonso was an enthusiast who ordered the translation of Picatrix,³¹ the textbook for magic to this day, and who took care in his Partidas to declare legal the study and use of non-diabolic esoteric knowledge. Only magic enabled one to predict an eclipse, or to measure heights through triangulation, or resorting to some mysterious scribblings to make calculations on wax tablets (the Indo-Arabic ciphers were introduced to Europe via Spain).³² Toledo was no doubt awash in magic, white, black and of every color. The usual suspects were, of course, the clergy, despite the fact that science was never considered a legitimate part of their ecclesiastical training, and that King Alfonso X himself forbade them to study the quadrivium. Throughout the Middle Ages, clerks were constantly admonished against the dual temptations of lust of the flesh and – that other lust of the intellect – magic, in which they equally liked to dabble. In what we could consider the beginning of the Spanish ‘black legend,’ Toledo itself also got its share of bad press, according to the saying In Toleto daemones.

The Learned King was very much aware of Castile’s backwardness, lacking as yet any recognized center of higher education. In 1254 he therefore founded the University of Salamanca on the model of Bologna, likewise conceived as a seedbed of lawyers. A modest endeavor, it did not shelter the sciences and, as usual in the West, ignored the quadrivium, with the single exception of a chair of music,³³ the first in all the Christian world. That same year Alfonso X took the logical, but until then unheard-of step, of founding in Seville what he called Estudios de arábigo. Historians of medieval universities have long been puzzled by this development, which they try to explain through a wild array of ill-educated guesses. It was Alfonso’s way to recognize that Spain was a divided country, where two different cultures lived – not mixed, but side by side. Just as Salamanca filled its chairs with faculty largely recruited abroad, Alfonso brought to his beloved Seville Muslim savants from the East. In both cases the set policy was to boost the sciences on a par with Latin learning in Castile.

Taking into account that natural science was for Alfonso X a part of philosophy, as it still was for Isaac Newton, his vast cultural project looks both intelligent and realistic. By opening wide the door to the sciences, and by trying to turn a weakness into an asset, the Learned King did not intend to break with the West, but to turn Spain into the absolute leader and herald of new times based on the golden promise of the sciences. Its study continued for a long time in those quiet, mostly Jewish hands. After the conquest of Valencia in 1238, Alfonso’s father-in-law Jaime I of Aragón refused to found a university, recognizing instead the freedom to teach by any qualified individual, that is, business as usual in keeping with the city’s Arab traditions. Alfonso X himself, to whom we must be grateful for extending to college professors the privileges of counts, took good care not to exclude those engaged in teaching at their homes el saber de las naturas.

The most profound and most permanent effect of the revival of Greek science was the re-discovery of the real Aristotle.Reference Lemay³⁴ Accessible at last in his own writings, the Philosopher brought forth the most unsettling upheaval in medieval intellectual history. In the late 12th century, the early arrival of the first translations of some minor libri naturales to Paris caused enthusiasm in many and quite a scandal in others. Aristotle’s influence could not but increase after the 13th-century translations of Averroes’ commentaries in Toledo and Sicily, to the point that Latin Averroism established forever the clear-cut autonomy of scientific thought.

The Learned King proclaimed Aristotle’s absolute authority: his legal and historical works are full of direct Aristotelian references and many undeclared insertions. Alfonso X extended credentials as great astrologers to Adam, to Abraham and to the mythical founders of civilizations,³⁵ on the way yielding some rather strange miscegenations, among them the idea of Virgil and Aristotle as the greatest magicians ever born in Spain.Reference Rico³⁶ Aristotle’s depiction as a Moor of al-Andalus, compounded by the rather weird astrological stuff attributed to him, helped distort his legitimate role in Spanish intellectual history. It was not until recently that scholars realized how Spain was not immune either to the Aristotelian onslaught. The key, once more, was the way in which those semi-underground schools worked at the vanguard of a no-holds-barred Averroism. Their activities became so widespread around 1293 that Alfonso’s heir Sancho IV wrote his Castilian Lucidario against the doctrines of the eternity of the world and the material nature of the soul that were being taught everywhere to eager young disciples.Reference Kinkade³⁷ The intellectual seduction of these schools, and the sheer shock they produced, is described in unequivocal terms by a young scholar to his former master at the book’s beginning:

There is perhaps no more clear-cut testimony than this of the challenge that radical Aristotelianism meant for the Middle Ages in human terms. The education offered at these schools was not conventional education, a kind of instruction that overflowed in pro- or con- first-class literature, with Ramon Llull, the book of Cavallero Zifar, Juan Ruíz’s Libro de buen amor and others. It was indeed Averroism, but not the Latin version, as it lived outside the universities and was taught in the vernacular by Jews, for which reason I have suggested we call it popular Spanish Averroism.

The sad last years of Alfonso X did not favor the completion of his great project, which trickled faintly into the reign of his son Sancho IV, but both its quality and quantity (only a fraction of which has survived) cemented his role as a lifeline for Spanish learning until the advent of the Renaissance. James II and Pedro IV (1319–1387) of Aragón did their best to continue Alfonso X’s commitment to astronomy, and so did the rulers of Toledo, at least until its last Mozarab archbishop, don Alonso García Gudiel (1280–1299) at the end of the 13th century.Reference Hernández and Linehan³⁹Mudéjar culture suffered a serious setback with the advent in 1369 of the Trastámara dynasty, committed to a Frenchified, reactionary and obsolete feudalism much opposed to Moors and Jews. The burning in 1434 of the library of astrology and magic of a member of the royal family, don Enrique de Villena by order of the bishop of Cuenca, fray Lope Barrientos,Reference Muñoz⁴⁰ shows the ground lost to ecclesiastical narrowmindedness.Reference Samsó⁴¹ This was no doubt a setback, but as yet it did not signal a complete demise, as some high noblemen continued to sponsor projects such as the translation of the Bible by the rabbi Mosé Arragel of Guadalajara,⁴² ordered by the Master of the Order of Calatrava don Luis de Guzmán from 1422 to 1434. Around 1440 the otherwise unknown bachelor Alfonso de la Torre wrote his Visión delectable de la philosofía e de otras çiencias Reference Negrón⁴³ for don Juan de Beamonte, provost of the order of Saint John of Jerusalem. Guided by Maimonides, and egregiously misread by E.R. Curtius,Reference Curtius⁴⁴ the Visión is obviously a product of those underground schools, rather close this time to Aragonese Jewries, where the most daring theses of the Arabs were carefully recorded in the vernacular. In the opinion of Marcel Bataillon⁴⁵ it could be used as a manual of sorts by judaizers, deists and atheists, which may be the reason for its many reprints after 1486 in the centers of the Marrano diaspora, one of them in Amsterdam (1626) by Spinoza’s father-in-law. An example, thus, of the far-reaching, delayed effects of the sowing carried out by Moors and Jews in the Spanish Middle Ages, and on which I cannot elaborate here.

Needless to say by now, that in this overview I have taken you on a breathless race across times, problems, events and personalities worthy of much more in-depth attention. The Toledan scientific effort was only made possible by the commitment of a multicultural society to a tacit, de facto collaboration to which Christians contributed their political power, and Moors and Jews their higher learning, finances, and skills in agricultural, arts, and crafts. Integrated in a functional model that we now call mudejarismo, and as of this moment the object of much scholarly debate, it was essentially peaceful as a modus vivendi beneficial to the all three religious communities. The big temptation here is to cast mudejarismo into a precociously modern liberal system of sorts, so let me hasten to say loud and clear that it was not. The Iberian peninsula remained for close to a millennium an area of confrontation between Christendom and Islam. As was to be expected, there were episodic wars and, on both sides, its share of fanatics. It was not, however, a land of jihad or Crusades – two sides of the same coin. It was a land of long and deep cultural interactions. There was a lot of racial muddling, as opposed to any shadow of ethnic cleansing. There is no problem today in recognizing that this was all basically due to the survival of Islamic foundations, which turned medieval Spain into a puzzling exception and a source of worry for Roman pontiffs, who repeatedly chided its kings (and especially Alfonso X) for coddling infidels and surrounding themselves with magicians and soothsayers. Nothing but common sense made everyone look the other way and eschew radical, divisive principles in favor of a pragmatic formula for a common life as free as possible of hate and turmoil. It could even give us, I think, some food for thought, now that the 20th century has witnessed the complete failure of nationalism, drowned in seas of human blood. The example of medieval Spain is a proof that cultures in themselves do not fatally throw men against men, that all of them have their treasure-trove of values to foster, to exchange, and cross-fertilize. Effects have their causes, and we can choose to work for reason and the building of bridges, instead of adding to the bonfires. To the members of the Academia Europaea, gathered under the canopy of philosophia naturalis, where the sciences and the humanities remain undivided, I will not say, for my departing salute, anything more sophisticated than a plain and simple: let us keep doing our duty.