  Damian’s reputation as a thinker who denies the universal validity of the principle of non-contradiction goes back to a series of studies that the German scholar J.A. Endres published early in the twentieth century (Endres 1906, Endres 1910, and some others). This notion is one of the central pieces in Endres’s more comprehensive thesis about a controversy between “dialecticians” and “anti-dialecticians” in the eleventh century — “dialecticians” being thinkers with a rational tendency while “anti-dialecticians” are suspicious of or hostile towards use of secular arts in discussions related to Christian faith. Peter Damian is Endres’s prime representative of the anti-dialectical attitude. Endres’s interpretation of Damian’s position ultimately depends on a single passage in De divina omnipotentia, passage 612A–B (in the Migne edition). To better understand that passage, some preliminary remarks about the content and aim of De divina omnipotentia should be made. (However, see also  Section 6.)