Suppose we assume that the parties in the original position took Kahneman and Tversky's prospect theory as constituting their general knowledge of human psychology that survives through the veil of ignorance. How would this change the choice situation of the original position? In this paper, I present what I call ‘prospect utilitarianism’. Prospect utilitarianism combines the utilitarian social welfare function with individual utility functions characterized by Kahneman and Tversky's prospect theory. I will argue that, once prospect utilitarianism is on the table, Rawls's original arguments in support of justice as fairness as well as his arguments against utilitarianism are, at best, inconclusive. This shows that how implausible a choice for utilitarianism in the original position is heavily depends on what one assumes to be general knowledge of human psychology that the original contracting parties know.

The original position together with the veil of ignorance have served as one of the main methodological devices to justify principles of distributive justice. Most approaches to this topic have primarily focused on the single person decision-theoretic aspect of the original position. This paper, in contrast, will directly model the basic structure and the economic agents therein to project the economic consequences and social outcomes generated either by utilitarianism or Rawls’s two principles of justice. It will be shown that when the differences in people’s productive abilities are sufficiently great, utilitarianism dominates Rawls’s two principles of justice by providing a higher level of overall well-being to every member of society. Whenever this is the case, the parties can rely on the Principle of Dominance (which is a direct implication of instrumental rationality) to choose utilitarianism over Rawls’s two principles of justice. Furthermore, when this is so, utilitarianism is free from one of its most fundamental criticisms that it ‘does not take seriously the distinction between persons’ (Rawls 1971 [1999]: 24).

Inspired by impossibility theorems of social choice theory, many democratic theorists have argued that aggregative forms of democracy cannot lend full democratic justification for the collective decisions reached. Hence, democratic theorists have turned their attention to deliberative democracy, according to which “outcomes are democratically legitimate if and only if they could be the object of a free and reasoned agreement among equals” (Cohen 1997a, 73). However, relatively little work has been done to offer a formal theory of democratic deliberation. This article helps fill that gap by offering a formal theory of three different modes of democratic deliberation: myopic discussion, constructive discussion, and debate. We show that myopic discussion suffers from indeterminacy of long run outcomes, while constructive discussion and debate are conclusive. Finally, unlike the other two modes of deliberation, debate is path independent and converges to a unique compromise position, irrespective of the initial status quo.

A defining characteristic of a liberal democratic society is the assignment of basic rights and liberties that protect each person's private sphere. Hence, social choice made in a liberal democratic society must at the very least be consistent with the exercise of each person's basic rights. However, even when everybody agrees to this basic principle, there could still remain irreconcilable social conflict and disagreement when it comes to the specific assignment of basic rights. This is especially so in a pluralistic society where there is a clash among radically different and incompatible world views. Philosophers have now started to focus on this issue, which now goes by the name 'perspectival diversity'. This paper extends the basic social choice theoretic framework of liberal rights by enlarging the domain to include individual perspectives alongside individual preferences. In this new framework, different individuals are able to see or perceive the same social alternative differently based on their own unique perspectives. The formal results of the paper imply that generating a viable social choice that is consistent with the assignment of basic rights can quickly break down once we start to increase the level of perspectival diversity in society.

John Rawls's most mature notion of political order is “stability for the right reasons.” Stability for the right reasons is the kind of political order that Rawls hoped a well-ordered society could ideally achieve. In this paper, I demonstrate through the tools of modern game theory, the instability of “stability for the right reasons.” Specifically, I will show that a well-ordered society can completely destabilize by the introduction of an arbitrarily small number of non-compliers whenever individuals fail to achieve full common knowledge ever so slightly.

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—namely, uncertainty, rather than people's egoistic psychology. Therefore, I claim that any game-theoretic model that does not incorporate uncertainty into the picture is 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 what type of person the other player is. 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.