What is justice? What does a just society look like? And what principles should guide us there? These questions have occupied an entire tradition - the dominant tradition - of political philosophy, led above all by Thomas Hobbes, John Locke, Jean-Jacque Rousseau, Immanuel Kant, and among contemporary philosophers by John Rawls and Robert Nozick.
But ask Amartya Sen and he will tell you they are precisely the wrong ones to ask. In his most recent book, The Idea of Justice, he argues that this traditional strain of political philosophy, which seeks to identify 'the just', or a single set of just principles that can then be used to design perfectly just institutions for governing society, reveals little about how we can identify and reduce injustices in the here and now.
According to Sen, the dominant approach, which he refers to as 'transcendental institutionalism', is beleaguered by two central problems: the problem of feasibility and the problem of redundancy. The first is a result of the practical difficulty, even impossibility, of arriving at a single set of principles that can help us to select just institutions through a process of impartial reasoning.
In Rawls' theory of justice, for instance, his two lexically ordered principles of justice are, it is argued, those that would be unanimously selected through an impartial decision procedure - through the hypothetical original position using the 'veil of ignorance' device. These principles then provide the basis for choosing actual institutions in the 'legislative stage'.
Clearly, however, much depends on the assumption that Rawls' two principles of justice are those that would indeed emerge from the original position. And Sen is skeptical that this is so.
In fact, Sen maintains that there are many principles that can pass the test of impartiality. He illustrates this point, first, using an anecdote about the competing claims of three children over the distribution of a single flute.
One child argues that they should receive the flute because they are the best flautist; the second, because they are the poorest of the lot; and the third, because they crafted the flute without help from the others. The three arguments are based, in turn, on principles of utility, economic equity, and the entitlement to the fruits of one's unaided efforts.
Each can be defended with strong, impartial arguments. And, returning to Rawls, it is similarly possible, for example, to provide substantial reasons for selecting Harsanyi's utilitarian principle in the place of Rawls' maximin principle as the basis for resolving distributional questions within a situation similar to the original position.
But this indeterminacy has profound implications for Rawls' theory of justice, for 'if there is no unique emergence of a given set of principles of justice that together identify the institutions needed for the basic structure of society, then the entire procedure of justice as fairness, as developed in Rawls' classic theory, would be hard to use'.
Sen even suggests that Rawls' basic claim about the emergence of a unique set of principles of justice from the original position (as defended in A Theory of Justice) was considerably qualified in his later writings, such as The Law of Peoples, and that accepting the full implications of these qualifications would mean abandoning the stage-by-stage theory of justice.
The second problem - the redundancy problem - is that the identification of fully just social arrangements is neither a necessary nor sufficient guide to reasoned choice of just policies, strategies or institutions. It is insufficient because, as Sen explains, 'the characterization of spotless justice, even if such a characterization were to emerge clearly, would not entail any delineation whatsoever of how diverse departures from spotlessness would be compared and ranked'.
In other words, using an analogy with paintings, the fact that a person regards Da Vinci's Mona Lisa as the most perfect picture in the world does not reveal anything about how they would rank a Picasso against a Van Gogh.
But it is also unnecessary because in adjudicating between the various merits of a Picasso and a Van Gogh there is no reason to identify the most perfect picture in the world, just as when determining the relative heights of Mount Kilimanjaro and Mount McKinley knowing that Mount Everest is taller than both is an entirely redundant fact.
In contrast to transcendental institutionalism, Sen advocates what he calls a 'realization-focused comparative approach'. In doing so, he sides with thinkers such as Adam Smith, Marquis de Condorcet, Jeremy Bentham, Mary Wollstonecraft, Karl Marx, and JS Mill, among others, who each attempted to evaluate the desirability of particular 'social realizations', rather than search for a set of perfectly just first principles.
It may not be possible to agree on perfectly just institutions, but, Sen contends, using a comparative approach we can at least arrive at widespread consensus on the injustice of certain practices or outcomes relative to others.
Such a comparative approach to questions of justice, he believes, is closely aligned with social choice theory, one of the many fields in which Sen made his mark as an economist, earning him a Nobel-prize in 1998. Social choice theory assumes that, like the plurality of impartial principles of justice that can plausibly sustain critical scrutiny, there can be a variety of competing principles that figure in our assessments of various social orderings.
And while it may sometimes appear to be impossible to satisfy all or even most of these competing principles at once - as in Kenneth Arrow's impossibility theorem, for example - such impasses can often be resolved by incorporating more information about interpersonal comparisons of well-being and relative advantages.
Similarly, Sen insists, 'for an adequate understanding of the demands of justice, the needs of social organizations and institutions, and the satisfactory making of public policies, we have to seek much more information and scrutinizing evidence'.
This, in particular, is something that Sen believes that Rawls' theory does not do well. Sen offers Rawls' use of the original position as an example of what he calls 'closed impartiality'. The 'veil of ignorance' device is, Sen admits, a useful, if hypothetical, way of reaching an impartial social choice, free of various vested interests. But it does not ensure the open scrutiny of the values of the people within the original position.
The vast plurality of alternative views held by outsiders - their unique moral perspectives and rankings of social realizations that can reveal hidden biases in our choice of basic principles - are simply beyond the scope of Rawls' theory. Furthermore, by limiting moral claims of outsiders we may be doing an injustice to those that fall outside the artificially closed circle of the original position.
Sen contrasts this example of 'closed impartiality' with the 'open impartiality' of Adam Smith's 'impartial spectator'. Smith's reflective device, which asks us to observe our actions and institutions from the standpoint of an outsider, specifically refrains from limiting the extent to which the views of others can be considered, refusing to confine moral discussion within the boundaries of a nation-state or any other locality.
And, as in social choice theory, such openness to, and critical reflection upon, alternative views and different ways of approaching social problems, Sen believes, can provide a more solid ground for ranking the 'just-ness' or, at least, manifest injustice of certain social realizations, even if they are merely partial and ordinal rather than comprehensive, cardinal rankings.
Of course, an engagement with contrary arguments does not imply that we will be able to arrive at agreed positions on every issue (and Sen does not see this as a drawback in his theory - not at all), nor does it oblige us to accept any of them. But there is a connection between what Sen calls the 'objectivity' of an ethical judgment and its ability to withstand open public scrutiny.
Sen thus underscores the importance of public reasoning for justice throughout the book, and he regards democracy, especially when understood as 'government by discussion' rather than the Schumpeterian 'government by elections', as a particularly appropriate form of public reasoning, which can serve to increase the 'objectivity' of political solutions.
Without doubt, the argument Sen presents in the The Idea of Justice deserves to be seriously considered by contemporary political philosophers and lay-readers alike. It commands respect, for even if it fails to convince it will surely sharpen the arguments of others.
Much of what passes for philosophy, including political philosophy, has been repeatedly accused of being irrelevant to the real choices and concerns of those outside of philosophy departments. And in The Idea of Justice Sen presents a serious challenge to those departments, forcing them to prove their relevance and demonstrate how they can actually inform tough decision-making.
However, if we are convinced by Sen's argument, this raises interesting questions about the role of the philosopher and their claim to any authority or special knowledge. According to Sen, 'philosophers' should not - and cannot - strive to become the architects of castles in the sky.
Instead, he asks us all to start right at the foundations: to share, explore, and debate our perspectives on how to repair the edifices in which we currently live. Justice arises not from a blueprint, but from a process of open public reasoning in which as many potential policies, strategies or institutions are considered as possible.
However, in this process it is not clear that the people who currently occupy philosophy departments have any special standing. They become, according to Sen, purveyors rather than adjudicators of wisdom, on an even standing with economists, doctors, scientists and lawyers, with whom they should collaborate intensely.
Sen's Philosopher turns out to be anyone willing to cross boundaries, willing to explore alternative ways of thinking and living across disciplines, communities and time. What matters is that people know more about what's out there and make more informed choices - that they are smarter - because, for Sen, smarter is better.
The Idea Of Justice by Amartya Sen is published by Harvard University Press
This article was originally published by Charles Barclay Roger, and openDemocracy.net under a Creative Commons licence (CC-BY-NC). To respond and share your views, join the debate at OpenDemocracy.net.
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