In his recent book, Killing in War, Jeff McMahan sets out a number of conditions for a person to be liable to attack, provided the attack is used to avert an objectively unjust threat: (1) The threat, if realized, will wrongfully harm another; (2) the person is responsible for creating the threat; (3) killing the person is necessary to avert the threat, and (4) killing the person is a proportionate response to the threat. The present article focuses on McMahan's second condition, which links liability with responsibility. McMahan's use of the responsibility criterion, the article contends, is too restrictive as an account of liability in general and an account of liability to be killed in particular. In order to defend this claim, the article disambiguates the concept of liability and explores its role in the philosophical analysis of the permission to cause harm to others.

Principles of sufficiency are widely discussed in debates about distributive ethics. However, critics have argued that sufficiency principles are vulnerable to important objections. This article seeks to clarify the main claims of sufficiency principles and to examine whether they have something distinctive and plausible to offer. The article argues that sufficiency principles must claim that we have weighty reasons to secure enough and that once enough is secured the nature of our reasons to secure further benefits shifts. Having characterized sufficientarianism in this way, the article shows that the main objections to the view can be avoided; that we can examine the plausibility of sufficiency principles by appealing to certain reasons that support a shift; and that we should be optimistic about the prospects for sufficientarianism because many of our strongest reasons seem to be of this sort. This shift, I claim, is the overlooked grain of truth in sufficientarianism.

This article discusses the relation between prioritarian and egalitarian principles, whether and why we need to appeal to both kinds of principle, how prioritarians can answer various objections, especially those put forward by Michael Otsuka and Alex Voorhoeve, the moral difference between cases in which our acts could affect only one person or two or more people, veil of ignorance contractualism and utilitarianism, what prioritarians should claim about cases in which the effects of our acts are uncertain, the relative moral importance of actual and expectable benefits, whether people should sometimes be given various chances of receiving benefits, and principles that appeal to competing claims.

It is widely held that the possibility of value-incomparability poses a serious threat to comparativism. Some comparativists propose to avoid this problem by supplementing the three traditional value relations with a fourth value relation, variously identified as ‘roughly equal’ or ‘on a par’. However, in a recent article in this journal, Nien-he Hsieh has proposed that the comparisons thought to require rough equality or parity could instead be understood in terms of the concept of ‘clumpiness’. Against this suggestion, Martin Peterson has argued that the concept of clumpiness allows agents to be exploited in money-pumps, thus removing the central appeal of the concept. In this note, I show that Peterson's argument fails to establish that the concept of clumpiness allows agents to be exploited in money-pumps.

This article is a response to commentaries on my book, Killing in War, by Cécile Fabre, Alex Leveringhaus and Victor Tadros. It discusses the implications of the approach I have defended for the morality of war for such issues as internecine killing in war, humanitarian intervention and the bases of individual liability to attack in war.

In this article I consider two consequentialist positions on whether individuals in affluent countries ought to purchase Fair Trade goods. One is a narrow argument, which asserts that individuals should purchase Fair Trade goods because this will have positive direct effects on poverty reduction, by, for example, channelling money into development. I argue that this justification is insufficient to show that individuals should purchase Fair Trade goods because individuals could achieve similar results by donating money to charity and, therefore, without purchasing Fair Trade goods. The second position has a wider focus. It notes both the direct effects of purchasing Fair Trade goods and possible indirect effects, such as the impact this might have on other individuals. I argue that certain actions, of which Fair Trade is one example, will be more likely to encourage individuals who would not otherwise contribute to poverty reduction to contribute and that this may produce additional positive value. Although space prohibits specific conclusions about Fair Trade, I note that considerations of this kind could give us reason to purchase such goods beyond those that issue from the direct effects of doing so and that, as such, they are crucial for determining whether individuals should purchase Fair Trade goods.

In the Preface to this enormous work, Derek Parfit makes a reference to Sidgwick's ‘great, drab book’ The Methods of Ethics (xxxiii). The juxtaposition of adjectives is amusing and oddly endearing; for Parfit, Sidgwick's drabness is not in any serious competition with his greatness. Parfit's two-volume book is not drab – though it can be exhausting – and, although it is probably too early to tell for sure, it also shows certain signs of greatness. Time and time again, one is impressed, even moved, by Parfit's enthralling and indefatigable resourcefulness and level of immersion in these issues, and by his dogged and transparently sincere commitment to discovering the truth about them. Despite its length, On What Matters demands careful study by everyone with a serious interest in philosophical ethics.