I propose a dynamical analysis of interaction in anarchy, and argue that this kind of dynamical analysis is a more promising route to predicting the outcome of anarchy than the more traditional a priori analyses of anarchy in the literature. I criticize previous a priori analyses of anarchy on the grounds that these analyses assume that the individuals in anarchy share a unique set of preferences over the possible outcomes of war, peace, exploiting others and suffering exploitation. Following Hobbes' classic (...) analysis of anarchy, I maintain that typically in anarchy some moderate individuals will most desire mutual cooperation while other dominators will most desire to exploit others' cooperation. I argue that once one allows for different types of individuals in anarchy, any a priori analysis of anarchy requires unrealistic assumptions regarding the agents' common knowledge of their situation. However, this move also suggests a dynamical analysis of anarchy, one that assumes no common knowledge. In the Variable Anticipation threshold model developed here, individuals modify their behavior as they learn from repeated interactions. I present specific instances of this model where the individuals in anarchy converge to different equilibria corresponding to either peace or war, depending on the initial conditions. I show that individuals are liable to converge to Hobbes' war of all against all even if only a small percentage of are dominators. The presence of only a few “nasty” individuals gradually drives all, including those inclined to be “nicer”, to imitate the “nasty” conduct of these few. This dynamic analysis suggests that the Hobbesian war in anarchy is indeed inevitable in most realistic circumstances. You have the same propension, that I have, in favor of what is contiguous above what is remote. You are, therefore, naturally carry'd to commit acts of injustice as well as I. Your example both pushes me forward in this way by imitation, and also affords me a new reason for any breach of equity, by showing me, that I shou'd be the cully of my integrity, if I alone shou'd impose on myself a severe restraint amidst the licentiousness of others. (David Hume, A Treatise of Human Nature) (Published Online July 11 2006) Footnotes1 Thanks to Luc Bovens, Sharon Lloyd, Brian Skyrms, Susanne Sreedhar and an anonymous referee for many helpful comments of early versions of this essay. (shrink)

Previous edition, 1st, published in 1971.

Since it appeared in 1971, John Rawls's A Theory of Justice has become a classic. The author has now revised the original edition to clear up a number of difficulties he and others have found in the original book. Rawls aims to express an essential part of the common core of the democratic tradition--justice as fairness--and to provide an alternative to utilitarianism, which had dominated the Anglo-Saxon tradition of political thought since the nineteenth century. Rawls substitutes the ideal of the (...) social contract as a more satisfactory account of the basic rights and liberties of citizens as free and equal persons. "Each person," writes Rawls, "possesses an inviolability founded on justice that even the welfare of society as a whole cannot override." Advancing the ideas of Rousseau, Kant, Emerson, and Lincoln, Rawls's theory is as powerful today as it was when first published. (shrink)

This paper critically examines several game theoretic interpretations of Hobbes' state of nature, including Prisoner's Dilemma and Assurance Game, and argues instead that the best matrix is that of a combination of the two, an Assurance Dilemma. This move is motivated by the fact that Hobbes explicitly notes two distinct personality types, with different preference structures, in the state of nature: dominators and moderates. The former play as if in a Prisoner's Dilemma, the latter play as if in an Assurance (...) Game. But when meeting one another, the Assurance Dilemma represents their differing strategies, and can explain various other features of Hobbes' state of nature, as well as a key informational role played the Sovereign. (shrink)

In this article, I argue that if one closely follows Hobbes' line of reasoning in Leviathan, in particular his distinction between the second and the third law of nature, and the logic of his contractarian theory, then Hobbes' state of nature is best translated into the language of game theory by an assurance game, and not by a one-shot or iterated prisoner's dilemma game, nor by an assurance dilemma game. Further, I support Hobbes' conclusion that the sovereign must always punish (...) the Foole, and even exclude her from the cooperative framework or take her life, if she defects once society is established, which is best expressed in the language of game theory by a grim strategy. That is, compared to existing game-theoretic interpretations of Hobbes, I argue that the sovereign plays a grim strategy with the citizens once society is established, and not the individuals with one another in the state of nature. (shrink)