An economic theory of government would explain why people support and pay for a political authority, starting from their self-centred reasons or pecuniary interests (Ménard, 1997). This way of framing the question of the origin of government sounds much like the old contract school, i.e. the systematic thinking about the government contract that dominatedWestern political philosophy from Grotius to Rousseau (Skyrms, 1996). But it also links up with themost recent developments in game theory, especially evolutionary game theory (Vega-Redondo, 1996). What, then, would lead rational players to set up andpay for a government in the short as well as the long run?