medieval philosophy and extraterrestrial life

Following the transmission of Aristotle's cosmology to the West, it was customary to accept that there was only one world and that man lay at the prime focus of God's attention. By the late 1200s, however, some scholars in the new European universities were beginning to point out that an omnipotent deity must have had complete freedom of creative action and so, in principle, could have made more than one world – though, in fact, he chose not to do so. A more radical challenge to Aristotle's dictum came in the late fourteenth century when it was suggested multiple worlds might indeed be possible within the geocentric paradigm.