Arab science spread to Europe not so much through contact with the Crusaders who came to the Near East in the eleventh and thirteenth centuries, but rather through the dynasties that ruled over Islamic Spain between the eleventh and fourteenth centuries. These were the Almorávides and later the Almohádes, who established their capital at Cordova. In this period, Spain was full of Arab translations of Greek and Latin scientific manuscripts. These works were studied and commented on by Muslim scholars like the twelfth-century Cordovan philosopher Ibn Rushd (known as Averroes in the West), whose commentaries on Aristotle are unequaled and who wrote treatises on medicine, grammar, law and astronomy. In Toledo, during the twelfth century, there was even a bureau for translating Arab manuscripts into Latin so that they could be sent to the rest of Europe. In 1277, the king of Castille had a Spanish-language compilation made of Arab astronomic works so that Spanish scholars could use them. In the same year, the secrets of glassmaking were transmitted to Venice in accordance with the provisions of a treaty between the prince of Antioch and the Doge. From that time on, there were innumerable transfers of technological knowledge.

It should also be recalled here that the technique for making paper, which had been learned by the Arabs from the Chinese in 751, had made it possible for a true market for books to develop in the Islamic world, and this had naturally encouraged the dissemination of scientific knowledge. This enormously important technique was transmitted to the West beginning in the twelfth century through the Emirate of Cordova. Paper-making then spread to Italy, or more precisely, Fabriano, where, in 1276, the first European factory for producing paper is thought to have been established. Other factories followed, especially at Troyes, France, in 1348 and at Nuremburg, Germany, in 1390. The material support for writing that had been transmitted by the Arabs facilitated the spread of ideas in Europe. Paper also led to a new invention — printing — around 1450. The printing press gave crucial impetus to the diffusion of knowledge, which has become the defining characteristic of our scientific world today.