Alcuin's Disputatio de rhetorica et de uirtutibus has traditionally posed problems of interpretation in terms of both form (its apparently bipartite structure) and content (as a digest of the rules of rhetoric combined with an exposition of the four cardinal virtues). However, a close reading of the sources from which Alcuin was drawing his argument (Cicero, Julius Victor, Fortunatianus, Marius Victorinus, Cassiodorus and, above all, Augustine and Quintilian) suggests why he should have chosen to emphasize the connection between rhetoric and the virtues in this particular way.