The importance of Siger in philosophy lies in his acceptance of Averroism in its entirety, which drew upon him the opposition of Albertus Magnus and Aquinas.
In December 1270 Averroism was condemned.
Renan, however, says that he merely tried to justify Averroism against the charge of heterodoxy.
Nearly three centuries latar, it was still studied at Padua, the last home of Averroism, and Lucilio Vanini speaks of him with great veneration.
In such a critical generation the words of Averroism found willing ears, and pupils who outran their teacher.
By the 14th century Averroism was the common leaven of philosophy; John Baconthorpe is the chief of Averroists, and Walter Burley has similar tendencies.
Meanwhile Averroism had come to be regarded by the great Dominican school as the arch-enemy of the truth.
The patricians of Venice and the lecturers of Padua made Averroism synonymous with doubt and criticism in theology, and with sarcasm against the hierarchy.
It was in the universities of north Italy that Averroism finally settled, and there for three centuries it continued as a stronghold of Scholasticism to resist the efforts of revived antiquity and of advancing science.
The parties seemed to have changed when Averroism thus took the side of the church; but the change was probably due to compulsion.
It was this comparatively mild Averroism, reduced to the merely explanatory activity of a commentator, which continued to be the official dogma at Padua during the 16th century.
Zabarella, Francesco Piccolomini (1520-1604) and Cesare Cremonini (15J0-1631) continued the traditions of Averroism, not without changes and additions.