This is the third volume in the series of St. Andrews Studies in Philosophy and Public Affairs, and I would think is just the kind of contribution which the founding Editor, Professor John Haldane, welcomes with enthusiasm. Graham Long links a detailed study of issues in contemporary ethics together with recent versions of political liberalism in a way which is at once challenging and plausible. His claim is that a particular understanding of ethical relativism, which he terms ‘coherence relativism’, is proof against the well known charges brought against relativism in any form; and that, so understood, it provides a suitable basis for political liberalism.

Relativism is often rightly accused of self‐destruction, or of a total failure to capture the nature of the moral judgements we might on occasion think ourselves justified in passing on cultures which are not our own. Long gives detailed consideration to the universalisms of Nagel, Habermas and Hampshire. Nagel's argument for objective values runs the risk, to put it no more strongly, of admitting as evidence only those moral views which Nagel himself would be willing to accept. Habermas offers a transcendental argument based on the unavoidable rules of rational discussion. Everyone, for instance, has an equal right to be heard, to question any statement, and so on: and the outcome of a discussion carried on in such a manner will be agreed universal principles. Long's reply is partly to claim that much of our moral discussion is far from exhibiting these particular features; and in any case that the implicit suggestion that everyone's views are somehow to be accorded equal weight is surely highly questionable. Hampshire, by contrast, seeks a basis for universalism in facts about human nature, its needs, and its gift of rational inquiry, from which we can see the emergence of the core elements which can form the basis of universal moral principles.

Long's own version of relativism takes its origin from the Rawlsian notion of reflective equilibrium. What one seeks is a set of moral beliefs in which one's pre‐reflective deepest moral commitments are respected and which is overall coherent. In reply to some of the more damaging objections usually made against relativism he argues that many of the more abhorrent moral views can properly be criticised ‘from the outside’, as it were, on the grounds that they are inconsistent with some well‐established factual beliefs. Racist views, for instance, are incompatible with well‐established non‐moral facts about human psychology. Moreover, it can generally be shown that abhorrent moral outlooks are internally, even if covertly, inconsistent. But while coherence relativism can provide at least some grounds for criticising other moral positions, it also provides good grounds for a certain level of tolerance for different moral convictions; since there are likely to be more than one justified (=coherent, etc) moral view, and it is wrong to impose one's own views on others unless ours are better justified than theirs, tolerance becomes a duty.

This is the link between ethics and political liberalism, to which the second and rather shorter part of the book is devoted. Political liberalism does presuppose some account of which beliefs are reasonably justified and which are not. Any account of reasonable disagreement involves accepting that people may justifiably hold beliefs with which one disagrees. It further entails that people, including myself, may on occasion justifiably hold beliefs which are false.

As one might expect from a book which has grown out of a doctoral thesis, it is argued in considerable detail, and demonstrates a firm grasp of the current state of debate in both ethical and political theory. Long's criticism of views such as those of Rawls, MacIntyre, Barry and Larmore are careful, precise, and fair. It also seems to me that in most cases they are also well aimed, and that Long's case is a very persuasive one indeed.

Perhaps the conclusion, that there is a form of moral relativism which is true, which justifies tolerance, and can properly be used to support political liberalism, is rather less controversial than might at first sight appear. The most extreme form of relativism involves a thesis about the radical incomparability of moralities within different cultures, and this remains open to all the criticisms usually levelled against it. Long has no intention of defending anything of this kind. He assumes that we can recognise views which are quite different from ours as moral views; he argues that there are defensible standards of reasonableness which are strong enough to form a shared basis for criticism, while yet being very different in the assessments they reach about moral issues. The key claim of his ‘coherence relativism’ is that there is no one uniquely justifiable ethical theory, even though each moral theory might claim to be of universal application. Consider, then, a serious moral dilemma – for instance, how to distribute an inadequate food supply in a camp full of starving refugees. Some analyses of moral dilemmas start from the assumption that in such situations any possible course of action will be wrong, and that any moral theory which allows for the existence of genuine dilemmas will fail to be action‐guiding. It might, however, be argued, as the Jesuit casuists of Louvain famously (or notoriously) did, that any action for which a reasonable case can be made out is permissible, even if none of them is either uniquely obligatory, or forbidden. On that view, it would be the case that the moral theory did not generate any uniquely justified course of action. Moreover, it is surely likely that any ethical theory which is sufficiently complex to deal adequately with the complexities of life is itself not in every case going to yield a uniquely justifiable view, if by that is meant a view whereby there is just one action which in the circumstances can be morally justified. If that is accepted, it is not simply that Long's coherence relativism is a view about competing moral theories; it would turn out to be a feature of any one moral theory. To that extent, it might not be thought to be relativist at all, as that term is often used.

But that, perhaps, is largely a matter of terminology. Long has produced a detailed and sustained argument on what is surely a central topic of moral and political debate. His book is not always an easy read, but it is a rewarding one, and much to be recommended.