Jokes about stupidity are extremely common in most countries, as ethnic, national, regional and locality jokes, political jokes, jokes about occupations and social classes, and blonde and Essex-girl jokes. The aim of this paper is to provide a theory that will explain why such diverse groups of people should be the butts of what is essentially the same joke. It will also explain jokes that are the opposite of the stupidity jokes, the widespread jokes about the canny (clever, crafty, calculating, stingy), whether jokes about ethnic groups, regional groups, townspeople or occupations. The key explanatory variables are first, the dominance of centre over periphery whether defined in geographical, cultural, language or social class terms and second, among the powerful, the contrast between those who hold arbitrary monopoly power based on control of the state and the means of force and those who have achieved their position through legitimate competition.