The subtitle of this book is `How the Arabs Transformed Western Civilization'; and in order to show this, Jonathan Lyons devotes the first 50 pages of a 200 page text principally to show how badly the West needed to be transformed.
When the First Crusade (about which we are given many unnecessary political details) began in 1096, the people of the West were rightly looked upon by the Arabs as coarse, brutish, and dirty; so ignorant that they could not even tell the time with any exactitude; their notion of justice involving trial by ordeal; their `medical' procedures which killed rather than cured; a clumsy numerical system they had inherited from the Romans; and with only scraps of knowledge of the achievements of antiquity having survived the barbarian invasions. In Europe, there was indeed some scholarship - we speak of a Carolingian and of an Ottonian Renaissance - but most learning was theological, and the official line of the Church was that any pragmatic attempt to understand the material world was suspect as being at best a distraction from seeking salvation and at worst a danger to it.
But there was also, among the violence, more peaceful interaction between the western invaders and the Arabs (and between the Arab invaders of Spain and the Christians there). Lyons describes how Arab scholarship of every kind had been promoted by the early Abbasid caliphs from the middle of the 8th to the first half of the 9th century (i.e. well before the First Crusade of 1096): by al-Mansur, Harun al-Rashid, and especially by al-Mamun, who had established the House of Wisdom as a great centre of learning and translations from Greek, Persian and Indian manuscripts.
Among the early westerners who were eager to learn what the Arabs had to offer was Roger II of Sicily (1095 to 1154), son of the Norman mercenary who had conquered Sicily from the Arabs between 1068 and 1091. He was already very knowledgeable about the achievements of the Arabs and brought Arab scholars to Sicily to extend that knowledge still further. A contemporary of Roger's was one Adelard of Bath (ca. 1080 to 1152) who in 1109 set out for the East specifically to see what he could learn from the Arabs, and who in Antioch came upon a treasure trove of Arab books. He was the most important of those who first transmitted Arab knowledge to the West. Lyons gives an excellent account of this hugely influential man, who not only translated Arab texts (like Euclid's Elements, translated from the Greek by the Arabs three centuries before Adelard brought it to Europe), but entered deeply into the spirit of scientific thought which was at the time quite alien to the West. Adelard produced the first comprehensive work on the astrolabe (which Lyons calls `the most potent analogue computer until the modern era', whose use had been refined by al-Khwarizmi in the 9th century and which was the most important tool for astronomy) and he introduced a translation of Ptolemy's Amalgest from the Arabic. Adelard certainly ought to be very much better known than he is.
At the College of Translators set up in Toledo in 1130 by its Archbishop Raymond , the most prominent of those working there was the industrious Gerard of Cremona (1114 to 1187), who translated no fewer than 87 books from Arabic into Latin.
Roger II's grandson, the Holy Roman Emperor Frederick II (reigned from 1220 to 1250), was another great patron of Arab learning, and it was under his patronage that Michael Scot produced translations from the great Arabic Aristotelians, Avicenna or Ibn Sina (980 to 1037) and Averroës or Ibn Rushd (1126 to 1198). From Italy the reception of Averroës spread to France and to the rest of Europe.
The earlier transmissions from the Arabic had for the most part been scientific, but now, with the reception of Avicenna and Averroës, they were also metaphysical, raising the question of the relationship between philosophy and religion. So when the Sorbonne became one of the great centres of Averroism, a battle broke out between the Averroists, headed by Siger of Brabant (1235 to 1281), and those who thought that the Aristotelian metaphysic was a threat to Christian orthodoxy. The immense achievement of the Dominican Thomas Aquinas (1225 to 1274) was to create a system in which Aristotelean/Averroist philosophy and Christian theology were seen as complementary and not as antagonistic. There was some resistance to this synthesis from the Franciscans, but in the end Thomism carried the day, and the canonization of Aquinas in 1323 ensured that the transformation of the West through Arab influence was safeguarded, and it is on that foundation that much of the later progress of western civilization would rest. Actually, the influence of Averroës would bear more fruit in the West than it would bear in the Islamic world - but that is another story.
Some readers may find some the technical details of both Arab science and Arab philosophy a little difficult to understand; but no reader will be left in any doubt that there was a time, lasting for at least three centuries, when the Islamic world was far more sophisticated and advanced than was the West and was indeed in many respects its teacher.