Flatlandis uniquely both a social critique and a primer on multi-dimensional geometry. Written in two parts in 1884 byEdwinA.Abbott, an English mathematician and theologian, it tells the story of a square living in Flatland: a two-dimensional realm. After a dream of a restrictive one-dimensional existence and the difficulties this poses, he is visited by a sphere from a three-dimensional space who wishes to enlighten him into the ways of “Upward,...