  The reentry of Aristotle into Europe caused a rebirth (a ‘renaissance’), but it also gave rise to a crisis, because it threatened to undermine the harmony established from the time of Augustine between the authority of reason, as represented by Greek philosophy, and the authority of faith, as represented by the doctrines of the Christian church. There were especially three ‘errors of Aristotle’ that seemed threatening: his teaching that the world was eternal, his apparent denial of personal immortality, and his denial of God's active agency in the world. (See, for example, Bonaventure, In Hexaemeron, VI.5 and In II Sent., lib. II, d.1, pars 1, a.1, q.2.) These three issues (‘the world, the soul, and God’) become in one form or another the focus of philosophical thought for the next six centuries.