Peter Vallentyne

This is the second volume of Oxford Studies in Political Philosophy. Since its revival in the 1970s political philosophy has been a vibrant field in philosophy, one that intersects with jurisprudence, normative economics, political theory in political science departments, and just war theory. OSPP aims to publish some of the best contemporary work in political philosophy and these closely related subfields. The papers in this volume address a range of central topics and represent cutting edge work in the field. They are grouped into three main themes: ideal theory, the moral assessment of states, and issues in social reliations.

I argue that the liberty condition of Sen's important impossibility of a Paretian liberal result is not a condition that liberals (or libertarians) would accept. The problem is that an appropriate liberty condition must be formulated in terms of consent - not in terms of preference. To formulate an adequate condition the framework needs to expand from collective choice rules (which only take information about preferences as input) to rights-based social choice rules (which also take as input information about which options have been consented to and which would violate someone's rights). I formulate a more adequate liberty condition based on the notion of consent that is acceptable to liberals, and then show that Pareto optimality is incompatible even with that condition. I then show how the liberty condition can be weakened in a plausible manner, and describe an interesting class of theories - rights-based Paretian theories - that satisfy the Pareto optimality requirement while being sensitive to liberty considerations.

Traditional act utilitarianism judges an action permissible just in case it produces as much aggregate utility as any alternative. It is often supposed that utilitarianism faces a serious problem if the future is infinitely long. For in that case, actions may produce an infinite amount of utility. And if that is so for most actions, then utilitarianism, it appears, loses most of its power to discriminate among actions. For, if most actions produce an infinite amount of utility, then few actions produce non-maximal utility, and so most actions are permissible.1 I will argue that potentially infinite futures create no major problems for utilitarianism. Utilitarianism has, I argue, the resources to distinguish among actions all of which produce infinite amounts of utility -- judging some permissible and some impermissible. For brevity of expression I will focus on act utilitarianism, but all the points apply equally well to many other traditional forms of utilitarianism

D. M. Armstrong, Michael Tooley, and Fred Dretske have recently proposed a new realist account of laws of nature, according to which laws of nature are objective relations between universals. After criticizing this account, I develop an alternative realist account, according to which (1) the nomic structure of a world is a relation between initial world-histories and world-histories, and (2) a law of nature is a fact that holds solely in virtue of nomic structure (and not, for example, in virtue of past history).