Nicholas of Cusa was a leading churchman, philosopher, and theologian of the fifteenth century. His career as canon lawyer, conciliarist, papal advocate, cardinal, and reformer placed him at the center of the political turmoil of his age. One of the era's most independent thinkers, he wrote extensively, first on political theory and later on speculative philosophy and theology. His political career and his treatise De Concordantia Catholica (On Universal Concord, 1433) have attracted the attention of historians and political scientists, while philosophers and theologians have focused on his speculative writings. Of the latter, De Docta Ignorantia (Of Learned Ignorance, 1440) is most familiar. Because this work focuses on human subjectivity and knowledge, Ernst Cassirer and others have considered it a decisive turn toward modernity. Yet, for all its novelty, Nicholas's thought remains deeply rooted in the medieval world. Of particular importance to his philosophy are the Neoplatonic thinkers, such as...