There is a concept which corrupts and upsets all others. I do not refer to Evil, whose limited realm is that of ethics; I refer to the infinite. I once longed to compile its mobile history. The numerous Hydra (the swamp monster which amounts to a prefiguration or emblem of geometric progressions) would lend convenient horror to its portico; it would be crowned by the sordid nightmares of Kafka and its central chapters would not ignore the conjectures of that remote German cardinal — Nicholas of Krebs, Nicholas of Cusa — who saw in the circumference of the circle a polygon with an infinite number of sides and wrote that an infinite line would be a straight line, a triangle, a circle, and a sphere (De docta ignorantia, I, 13, [1]. Five, seven years of metaphysical, theological, and mathematical apprenticeship would allow me (perhaps) to plan decorously such a book. It is useless to add that life forbids me that hope and even that adverb [2].