De ludo globi

De ludo globi (The Game of Spheres, The Ball Game, or The Globe Game) is a book by the fifteenth-century philosopher, theologian and cardinal Nicholas of Cusa. It was written in Rome and completed in October 1463.

The work consists of two dialogues. The first takes place between Cusanus and John IV, Duke of Bavaria; the second between Cusanus and John's brother, Albert IV, also Duke of Bavaria. In the first, Cusanus rests after playing a newly invented ball game and observes that no honest game is entirely lacking in the capacity to instruct. He compares the motion of the misbalanced ball to the soul of man, set in motion by God, and then turns to a game of knowledge he had devised and defined.