In the 11th century Europe had settled down, after centuries of war and invasion, into a condition of comparative political stability, ecclesiastical discipline, and social tranquillity: the barbarians had been converted, and, as in the case of the Normans, had pressed to the forefront of civilization; civic life had developed in the fortified towns of Italy, raised as defences against the pressure of Saracen and Hungarian invasions. Soon, communication with the East by trade and in the Crusades, and with the highly cultivated Moors in Spain, further stimulated the new burst of intellectual life. Arabic renderings of some of the works of Aristotle and commentaries on them were translated into Latin and exercised a profound influence on the trend of culture. A new translation of Aristotle's _Metaphysics_ appeared in 1167, and by the beginning of the 13th century all his physical, metaphysical and ethical treatises were available, and during the next half century the translations from Arabic versions were superseded by renderings direct from the original Greek. As expositions of the real doctrines of Aristotle the translations from the Arabic left much to be desired. Renan calls the medieval edition of the _Commentaries_ of Averroës "a Latin translation of a Hebrew translation of a commentary made upon an Arabic translation of a Syriac translation of a Greek text." The study of such works often led to the enunciation of doctrines held heretical by the theologians, and it was only when the real Aristotle was known that it was found possible to bring the Peripatetic philosophy into the service of theology.