Eshu walks the boundary path between two friends' fields wearing a hat that is red on one side and black on the other, then returns the other way. By evening they are fighting about what color the stranger's hat was, each certain, each honest. The story is the tradition's lesson about perspective and about Eshu himself: he is not evil, he is the friction that makes people examine their certainty, and missionaries who translated him as Satan misread the tradition badly.