The Averrhoïst was not the only Latin version of Aristotle current in western Christendom in the twelfth century. The capture of Constantinople by the crusaders in 1204 had brought Catholic Europe directly into contact with Greek philosophy, and translations direct from the Greek into Latin had been attempted, one of the earliest being made by Bishop Grosseteste. Various translations of Aristotle were, then, available. Were they to be regarded as open without restriction to the curious eye of scholarship? The Church decided against such freedom. In 1210 a council of the ecclesiastical province of Sens, held at Paris, having publicly condemned the heresies of Amaury de Bène, went on to protect the unwary from another source of possible contamination by commanding that neither the works of Aristotle nor the commentaries upon him should be read in Paris under pain of excommunication.[83] The commentaries referred to must be either those of Averrhoës or similar Arabian treatises. In 1215 this prohibition was renewed by the papal legate, under whose supervision the schools of Paris came. Gregory IX, in a regulation addressed to the masters and students of Paris on April 13, 1231, made the prohibition provisional, until such time as the books of Aristotle could be examined and expurgated. At the same time he entrusted this important task to William of Auxerre and two others. The project is very much to the credit of the Pope, a genuine supporter of learning who, however, had probably not realized how great an undertaking it was. At all events it came to nothing; and the prohibition, although renewed by Urban IV, in January 1263, would appear to have remained a dead-letter. In 1255 the 'Physics' and 'Metaphysics' of Aristotle were prescribed for the course in the Arts' faculty in the University. In fact the Aristotelian impulse in the vivid and vigorous atmosphere of the youthful Parisian schools was too strong. Neither Aristotle nor Averrhoës could be got rid of by papal inhibition. The keenest interest had been aroused in them. It were better, as it was simpler, to utilize such keenness rather than to attempt to combat it. Of all the great services rendered to the Church by the Dominican order none was greater than its capture of profane learning for orthodox Christianity. The great Franciscans were expounding the current theology of the day with its tinge of Platonism; the Dominicans now came forward to adapt Aristotle for the service of Christianity. In 1256 Alexander IV commissioned Albertus Magnus to write his 'De unitate intellectus contra Averroëm': a fact that is proof positive of the headway that had already been made not only by Aristotelianism but by the tenets of the 'great commentator.' The tractate is indeed written against Averrhoës himself, not Averrhoïsts, but the fact that the Pope entrusted Albert of Cologne with the task of answering the former is evidence of the activity of the latter.[84] Fifteen years later Thomas Aquinas produced another work on the same subject: but this one definitely 'contra Averroïstas.' Between the years 1261 and 1269 Aquinas was, together with William of Moerbeke, at the court of Rome engaged upon the great task, now at length undertaken under the auspices of the Holy See, of making a translation and commentary on Aristotle. In the latter year he appeared at Paris on the occasion of the assembly there of a chapter-general of the Dominican order. It has been maintained that the real reason of his presence was to clear the Prædicants of the suspicion of Averrhoïsm.[85]