On Learned Ignorance

A treatise in three books, finished in 1440. In the dedication to Cardinal Julian Cesarini, Nicholas says its guiding idea came to him at sea, on his way back from Constantinople. Learned ignorance means knowing that one does not know: a finite mind measures by comparing more and less, so it can never reach the infinite, just as a polygon with ever more sides approaches a circle without becoming one. Book I treats God as the absolute maximum, in which maximum and minimum coincide, and uses mathematical images, such as an infinite line that is also a triangle, a circle and a sphere, to point beyond reason. This is the coincidence of opposites. Book II treats the universe as a contracted, or limited, maximum. Here Nicholas argues that the world has no fixed centre or edge, so the earth is neither at the centre nor wholly at rest. Book III treats Christ as the maximum both absolute and contracted, uniting God and creation.

It joins mystical theology, mathematics and cosmology in an original way, and its account of the limits of knowledge and its universe without a fixed centre look ahead to early modern thought.