One of John Rawls’s major aims, when he wrote A Theory of Justice, was to present a superior alternative to utilitarianism. Rawls’s worry was that utilitarianism may fail to protect the fundamental rights and liberties of persons in its attempt to maximize total social welfare. Rawls’s main argument against utilitarianism was that, for such reasons, the representative parties in the original position will not choose utilitarianism, but will rather choose his justice as fairness, which he believed would securely protect the (...) worth of everybody’s basic rights and liberties. In this paper, I will argue that, under close formal examination, Rawls’s argument against utilitarianism is self-defeating. That is, I will argue that Rawls’s own reasons, assumptions, and the many theoretical devices he employs demonstrably imply that the representative parties in the original position will choose utilitarianism instead of justice as fairness. (shrink)

Philosophers and social scientists have recently turned to game theory and agent-based models to better understand social contract formation. The stag hunt game is an idealization of social contract formation. Using the stag hunt game, we attempt to determine what, if any, barrier diversity is to the formation of an efficient social contract. We uncover a deep connection between tolerance, diversity, and the social contract. We investigate a simple model in which individuals possess salient traits and behave cooperatively when the (...) difference between their trait and the trait of their counterpart is less than their ‘tolerance level’. If traits are fixed and correspond to permanent or semipermanent features of the individual, such as religion or race, social contract formation is a remote possibility. If traits are malleable, social contract formation is possible but comes at the steep cost of diversity and tolerance, that is, individuals are unwilling to cooperate with those much different from themselves. Yet homogeneity and intolerance are not a long-term feature of the population. Over time mutations allow for increasingly tolerant agents to prosper, thereby ushering in trait diversity. In the end, all reap the benefits of cooperation. (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)

Now it is plain that such consequences as these conflict sharply with common-sense notions of morality. If we had been obliged to accept Psychological Egoism, in any of its narrower forms, on its merits, we should have had to say: 'So much the worse for the common-sense notions of morality!' But, if I am right, the morality of common sense, with all its difficulties and incoherences, is immune at least to attacks from the basis of Psychological Egoism.

Hobbes has served for both philosophers and political scientists as the paradigm case of someone who held an egoistic view of human nature. In this article I shall attempt to show that the almost unanimous view that Hobbes held psychological egoism is mistaken, and further that Hobbes's political theory does not demand an egoistic psychology, but on the contrary is incompatible with psychological egoism. I do not maintain that Hobbes was completely consistent; in fact, I shall show that there was (...) a continuous development in Hobbes's works away from an egoistic psychology. But I do think that the main outlines of Hobbes's political theory, i.e., his account of the laws of nature, the right of nature, the obligations imposed by laws and covenants, and the rights and duties of citizen and sovereign, are essentially the same in The Elements of Law, De Cive, and Leviathan. I thus hold that even in his earliest work, The Elements, the only one where a charge of egoism is justifiable, the political theory does not depend on egoism. But the first and most important point to be established is that Hobbes did not hold an egoistic psychology. (shrink)

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)

Hobbes believed that the state of nature would be a war of all against all. Locke denied this, but acknowledged that in the absence of government, peace is insecure. In this paper, I analyse both accounts of the state of nature through the lens of classical and experimental game theory, drawing especially on evidence concerning the effects of punishment in public goods games. My analysis suggests that we need government not to keep wicked or relentlessly self-interested individuals in line, but (...) rather to maintain peace among those who disagree about morality. (shrink)

Many commentators think that Hobbes was committed to psychological egoism. Psychological egoism is a theory of human psychology that claims that all human actions are ultimately motivated solely by one’s own self-interest. In this paper, I argue that there are reasons to think that Hobbes was not committed to psychological egoism in any of its plausible formulations.

Hobbes’s own justification for the existence of governments relies on the assumption that, without a government, our lives in the state of nature would result in a state of war of every man against every man. Many contemporary scholars have tried to explain why universal war is unavoidable in Hobbes’s state of nature by utilizing modern game theory. However, most game-theoretic models that have been presented so far do not accurately capture what Hobbes deems to be the primary cause of (...) conflict in the state of nature – which is uncertainty, rather than people’s egoistic psychology. Any game- theoretic model that does not incorporate uncertainty into the picture is, therefore, I claim, the wrong model. In this paper, I use Bayesian game-theory to show how universal conflict can break-out in the state of nature - even when the majority of the population would strictly prefer to cooperate and seek peace with other people - due to uncertainty about the other person’s type. Along the way, I show that the valuation of one’s own life is one of the central mechanisms that drives Hobbes’s pessimistic conclusion. (shrink)

If it was a matter of hunting a deer, everyone well realized that he must remain faithful to his post; but if a hare happened to pass within reach of one of them, we cannot doubt that he would have gone off in pursuit of it without scruple..." Rousseau's story of the hunt leaves many questions open. What are the values of a hare and of an individual's share of the deer given a successful hunt? What is the probability that (...) the hunt will be successful if all participants remain faithful to the hunt? Might two deer hunters decide to chase the hare? (shrink)

Barbara Fried takes the view that uniform taxation—that is, a single rate applicable to all income levels—cannot be defended on any grounds of justice. She goes further by saying that, of all possible rate structures, it might be “the hardest one”? to ground in “a”? theory of fairness. Using the contractarian-constitutional perspective advanced by John Rawls and James Buchanan, this article argues that tax uniformity can be seen as a requirement of justice. After modelling how the political world realistically decides (...) to distribute tax shares (self-interested parties act under a majority constraint), I show how the uniformity principle could emerge from the constitutional contract. In other words, rational individuals would choose uniformity as a procedural constraint under a “veil of uncertainty”?; that is, with limited knowledge regarding their positions under the future application of the rule. Moreover, I elucidate how the uniformity requirement integrates generalized criteria of fairness and efficiency into fiscal politics as it precludes fiscal exploitation and constrains majorities, and their most influential subgroups, to opt for policies in the direction of the Pareto frontier, and as such promotes outcomes acceptable to all participants. (shrink)