Praecisio and Conjecturae: Cusanus’ Ball Game and the ‘Learned Ignorance’ of the World

Nicholas Cusanus’ De Ludo Globi (1463) is not about tennis, nor does it pave the way for the achievements of the so-called Scientific Revolution. Nevertheless, in a broad sense Cusanus might be viewed as a progenitor of the ‘scientific’ ball player: beyond any impossible, vain, or metaphysical guarantee, scientific knowledge of the finite physical world consists in making conjectures (coniecturas), and making conjectures means literally to throw (conicere). Throwing balls and projectiles toward a target, however, eludes infinity. I will follow in Cusanus’s wake in interpreting ludus not as a pastime, but as a speculationis figuratio, keeping in mind two interpretations of this “ball game” that may be viewed as opposite to each other: Pierre Duhem’s hypothesis that Cusanus was proposing a formulation of the Galilean notion of inertia, and Hermann Hesse’s linking of the “prehistory” of The Glass Bead Game to Cusanus.