EN
John the Scot Eriugena, the main figure of the ninth century philosophy, was involved in the most original debates of the Carolingian Renaissance i.e. in the controversy over double predestination. Having examined the problem and having refuted the concept presented by his opponent Gottschalk of Orbais, Eriugena emphasized the role of reason, and introduced semantic and rhetoric, which was an innovative way of argumentation at that time. Liberal arts had been thus shown to be of a great importance in theological and philosophical disputes.