Thomas Aquinas

===Quarrelsome second Paris regency (1269–1272)===
[[File:Benozzo Gozzoli - Triumph of St Thomas Aquinas - WGA10334.jpg|thumb|''Triumph of St Thomas Aquinas'', {{lang|la|Doctor Communis}}, between Plato and Aristotle, [[Benozzo Gozzoli]], 1471. [[Louvre]], Paris.]]

In 1268, the Dominican Order assigned Thomas to be regent master at the University of Paris for a second time, a position he held until the spring of 1272. Part of the reason for this sudden reassignment appears to have arisen from the rise of "[[Averroism]]" or "radical [[Aristotelianism]]" in the universities. In response to these perceived errors, Thomas wrote two works, one of them being ''De unitate intellectus, contra Averroistas'' (''On the Unity of Intellect, against the Averroists'') in which he reprimands Averroism as incompatible with Christian doctrine.{{sfn|Stump|2003|pp=10–11}} During his second regency, he finished the second part of the ''Summa'' and wrote ''De virtutibus'' and ''De aeternitate mundi, contra murmurantes'' (''On the Eternity of the World, against Grumblers''),{{sfn|Davies|2004|p=5}} the latter of which dealt with controversial Averroist and Aristotelian ''beginninglessness'' of the world.{{sfn|Stump|2003|pp=11–12}}

{{See also|Eternity of the world}}

Disputes with some important [[Franciscans]] conspired to make his second regency much more difficult and troubled than the first. A year before Thomas re-assumed the regency at the 1266–67 Paris disputations, Franciscan master William of Baglione accused Thomas of encouraging Averroists, most likely counting him as one of the "blind leaders of the blind". [[Eleonore Stump]] says, "It has also been persuasively argued that Thomas Aquinas's ''De aeternitate mundi'' was directed in particular against his Franciscan colleague in theology, [[John Pecham]]."{{sfn|Stump|2003|pp=11–12}}

Thomas was deeply disturbed by the spread of Averroism and was angered when he discovered [[Siger of Brabant]] teaching Averroistic interpretations of Aristotle to Parisian students.<ref>{{cite book| author= Thomas Aquinas| title= Reader| pages= 9–11}}</ref> On 10 December 1270, the Bishop of Paris, [[Étienne Tempier]], issued an edict condemning thirteen Aristotelian and Averroistic propositions as heretical and excommunicating anyone who continued to support them.<ref>McInerney, ''Against the Averroists'', p. 10.</ref> Many in the ecclesiastical community, the so-called Augustinians, were fearful that this introduction of Aristotelianism and the more extreme Averroism might somehow contaminate the purity of the Christian faith. In what appears to be an attempt to counteract the growing fear of Aristotelian thought, Thomas conducted a series of disputations between 1270 and 1272: ''De virtutibus in communi'' (''On Virtues in General''), ''De virtutibus cardinalibus'' (''On Cardinal Virtues''), and ''De spe'' (''On Hope'').<ref>{{cite book| author= Thomas Aquinas| title= Reader| page= 11}}</ref>