Amartya Sen’s The Idea of Justice will go straight on to the reading lists for all relevant courses on justice and ethics, but it deserves a much wider readership too. It sets out a persuasive and possibly even practical approach to questions of social justice, drawing on Sen’s previous work on both social welfare and capabilities, placed in the context of the past literature from Kant and Hobbes to Rawls and Nozick. It’s also accessibly written, for a serious philosophy book anyway. I certainly managed it on the beach (see below).

The key distinction Sen draws between types of theory of justice is the contrast between those which set out an ideally just set of social arrangements and those which are instead concerned with ways to compare one actual set of social outcomes with another. In the former category are Hobbes, Locke, Rousseau, Kant, John Rawls. In the latter Adam Smith, Condorcet, Mary Wollstonecraft, JS Mill, Marx. So rather than some of the conventional ways of categorizing theories, eg is it utilitarian or not, he asks whether or not a theory offers a means to assess reductions in injustice. The focus is on direction of travel rather than ideal end-states. I for one find this a much more compelling approach than the abtract debates about ideal outcomes which were the standard fare in my student days.

Sen’s approach leads on to a number of other appealing features in his approach to social justice. He argues that we must accept there will always be a plurality of views, given that we’re comparing different social welfare outcomes rather than trying to identify a single global maximum. He also insists that it is essential to include an assessment of how people actually behave in any institutional framework. The justness or otherwise of an outcome depends on the institutions but also actual behaviour, the procedures for bringing about different outcomes, and the final outcomes themselves. It is a sort of whole supply chain view of justice.

He argues furthermore that the measure of ‘success’ in societal outcomes should not be utilities but rather capabilities. This is a big divergence from the utilitarianism-inspired well-being agenda, and again I’m on Sen’s side of this debate. The capabilities approach ensures that freedom and agency are included in welfare assessments, and therefore avoids the very unappealing paternalism of many of the authors who leapt onto the happiness bandwagon.

Finally, he places a great deal of emphasis on the importance of reasoning in general and the importance of public reasoning in particular, for the removal of injustices. Moving towards a less unjust society will require a reasoned public debate. Sen uses the same device as Adam Smith, the idea of what an impartial spectator would think, as a tool for making assessments of the fairness of a set of outcomes. Justice requires the effort to be impartial – and that includes taking account of external perspectives, outside a particular society. This, Sen argues, is particularly important in thinking about justice in a globalized economy. To argue that global justice would require a new set of ideal global institutions is, he believes, a dead end.

The book left me with one question and one minor complaint. The question is the extent to which Sen’s approach does have practical bearing on policy. Take the debate about ‘free’ versus ‘fair’ trade, caricatured as it often is. Like many conventional economists, I’m highly sceptical about fair trade, suspecting that it might distort markets and counterproductively damage livelihoods by reducing trade. Taking Sen’s approach to justice would help me distinguish the rationale for my view from an idealist with a certain view about the shape of the world. But not, I think, from a fair trader with different views about what is and is not pragmatic and moving in the right direction in terms of social justice. The inevitable plurality Sen describes seems to imply this.

The minor complaint is that Sen spends more time than made for a smooth read on setting out in great detail his differences from John Rawls and The Theory of Justice. Rawls was so dominant in the field that it is helpful to understand the differences, but some of the detail could helpfully have been relegated to an appendix. Still, this is just a quibble about an important book.