Learning Functional Programming in Go

Roger Godement (1958)

In 1958, Roger Godement wrote a book on the sheaf theory that first introduced the concept of monads. Sheaves are objects that capture local data about a manifold, yet in doing so, allows one to see global properties of space as a whole. What's a manifold? It's a geometric object, for example, the Earth. From where you stand or walk, it looks like it goes on for ever. However, if you walk around the Earth enough times, you'll realize that it's a sphere. What Godement called a standard construction was subsequently called a monad by Saunders Mac Lane, and that name stuck.