Jean Gerson, moral certainty and the Renaissance of ancient Scepticism

The early modern revival of scepticism and new scholastic trends in guiding uncertain consciences originated in the 15th century. This paper explores the motivating role of the Great Western Schism (1378–1417) on these developments, focusing on the work of the eminent theologian and philosopher Jean Gerson (1363–1429). The Schism created a rationale for a pluralistic handling of opinions and for a positive attitude towards scepticism, as Gerson's writings document. Moreover, innovations in the scholastic treatment of uncertainty, culminating in Gerson's concept of a moral certainty, made ancient scepticism palatable for scholastics. Hence, two major early modern traditions of dealing with uncertainty, the sceptic and the scholastic, were interrelated at the beginning. Gerson also addressed the problem of a reliable criterion of religious truth which Richard Popkin tied to the Reformation. The problem was much discussed well before the Reformation, notably in connection with the question of distinguishing true from false prophetic knowledge. The Schism, however, disqualified the Catholic hierarchy as arbiter of truth and motivated a reconsideration of established notions of epistemic uncertainty.