It is difficult to think of a time when liberal political thought has been as remote from political practice as it is today. There are many reasons for this situation, including the near-complete rout of liberal forces by the right. But a part of the reason lies in the development of liberal thought itself. Liberal thinkers, in the universities where they have retreated, appear to believe their main task is to specify the basic liberties of individuals and the principles of distribution for other social goods, in the conviction that once these have been identified they can be embodied in law and interpreted by courts. In this now conventional view the principles of justice can be derived from an underlying moral consensus that is embodied in modern democratic societies, and since these will be principles that all reasonable people can accept, there will be no possibility of radical political conflict. No doubt there will still be some need for political activity, but not in order to protect liberal values. Liberal values will not be at risk, since they will be enshrined in law.

The currently dominant version of liberal theory is a species of legalism in which politics takes second place to the judicial interpretation of rights. If this view of liberalism is now commonplace it is largely due to the impact of John Rawls’s theory of justice. Rawls revived a version of social contract theory that has shaped the way political philosophy is practiced in the United States, and to a lesser extent in Britain and other European countries. It is a feature of contract theories that they look to agreement on principles of justice to avoid conflict over religious beliefs and moral ideals. There have been many such theories–Locke’s account of what justice demands is quite different from that of Hobbes, and Rousseau’s is different from both–but that has not diminished the appeal of the idea that government can be seen as embodying some sort of contract. The vision expressed in contract theory is of a society in which the murky compromises of politics are replaced by the rule of law, and people with widely different beliefs and values can live together under a regime of justice that all can accept.

It is a seductive vision, but there has always been something unreal in the view that law can achieve such a feat. People differ as much in their conceptions of justice as they do in their religious beliefs and moral values, and the idea of an overlapping moral consensus, which Rawls’s theory invokes, scarcely reflects the condition of contemporary democratic societies. It is true that the language of justice and rights is pervasive, but it conceals vast divergences in moral outlook and world-view. What do gay activists and homophobic fundamentalists, liberal feminists and right-to-life fanatics, Green defenders of the natural environment and those who see the planet as a resource to be used by humans have in common? They may have some shared beliefs or values, but these are hardly sufficient to generate agreement on which human liberties are most important or on how other social goods are to be distributed. The fact is that contemporary democratic societies lack any deep consensus on values, hence the peculiarly fractious quality of contemporary politics in the “liberal” West.

That Rawls’s theory has little to say on many of the issues that are currently most politically contested has not prevented his heirs from trying to extend his work to precisely these questions. Martha Nussbaum’s most recent book, Frontiers of Justice, is the latest such effort. She aims to widen the reach of Rawlsian theory by addressing questions it has thus far largely neglected, such as the role of distributive justice in international relations, the claims of disabled people and the moral status of nonhuman animals. Nussbaum’s resourceful and imaginative exploration of Rawls’s work displays a command of the longer tradition of political philosophy that matches and even surpasses that of Rawls, along with a notably richer sensitivity to the history and variety of constitutional arrangements. The result is a notable contribution to philosophical inquiry that merits the most careful study by all who try to think seriously about public policy.

Still, a puzzle remains as to why Nussbaum has chosen to view the issues with which she is concerned through the lens of Rawlsian theory, when she could–perhaps more profitably–have examined them in the light of her own views. As she is fully aware, applying Rawls’s theory to these areas is no easy matter. His vision of a scenario in which principles of justice are adopted is an idealized version of rational choice by competent human adults. Since the theory makes no reference to disabled persons, children or nonhuman animals, it is hardly surprising that the principles that emerge from it give no clear guidance as to how they are to be treated. Again, Rawls’s theory was constructed to apply within modern states. It was never meant to be a charter for global redistribution. In later work he tried to develop some account of morality in international relations, but he was clear that his conception of justice reflected a moral consensus that exists (so he believed) within nation-states and could be implemented only by nation-states. When Rawls failed to apply his theory to the issues Nussbaum raises, it was not an oversight. It was because the structure of the theory he constructed precluded it from being applied in these ways.

Thus, in order to extend Rawls’s account of justice to such issues, Nussbaum has to make major alterations in the theory. One can’t help but wonder why she takes the trouble to make these elaborate adjustments, especially as she concedes that many of Rawls’s conclusions can be reached through other types of argumentation. Why does she force her deliberations into the Procrustean mold of Rawls’s contract theory? The reason may be the canonical prestige of Rawls’s theory. Nussbaum’s attitude toward Rawls’s work is one of piety, and this leads her to accept aspects of his theory that critical reflection might have led her to question. She writes of Rawls’s theory that its

principles themselves, or something very like them, are good principles–not only for those cases to which Rawls applies them, but for other cases concerning which he advances no principles at all. Moreover, the ideas of fairness and reciprocity that these principles embody and render concrete are themselves deeply attractive ethical ideas…. It would be good to extend those principles and those ideas to our unsolved problems of justice.

As these remarks show, Nussbaum does not question the idea that the problem areas she identifies for Rawls’s theory concern issues of justice. But why should this be assumed? Nussbaum mentions the alternative view presented in Utilitarianism in which it is the promotion of well-being and the avoidance of suffering rather than any idea of justice that is fundamental–only to reject it as being obviously inferior to Rawls’s Kantian approach. It is true that Utilitarianism has many problems, some of them insoluble. At the same time it does seem to me to have one large advantage over Rawls’s approach, which is that it is not a reiteration of received opinion.

Rawls’s method in moral theory is a process of “reflective equilibrium” that involves clarifying our moral intuitions and shaping them into a coherent whole. In its nature this method can do no more than turn the moral beliefs expressed in current opinion into something like a system. In contrast Utilitarianism appeals to features of the world that stand outside our moral beliefs, and that could compel us to revise them. In this respect Utilitarianism seems better equipped to deal with a number of difficult moral issues, particularly those arising in our relations with other animal species. Once again, Nussbaum is fully aware of this difficulty:

The whole idea of a justification that looks for a reflective equilibrium and uses the idea of overlapping consensus is an anthropocentric idea. The holism in ethics that Rawls and I share may be contested at this point by a reasonable Benthamite, who will insist that what justifies changes in our treatment of animals is not the coherence of a family of human theories and judgements, even bolstered by reasonable agreement and overlapping consensus; it is, instead, a fact utterly external to the human point of view, namely animal suffering.

I am not a disciple of Jeremy Bentham, but it was Bentham who observed that it is not whether animals can think that matters but that they can suffer. Those who oppose animal experimentation–as I do myself–do so not because it cannot be fitted comfortably into a theoretical reconstruction of prevailing moral attitudes but because they believe these attitudes to be defective. If Bentham had aimed only to systematize the moral beliefs of his day he would not have been one of the first Western thinkers to give animal suffering proper attention. With all its difficulties Utilitarianism allows a critical distance from received opinion that Rawls cannot provide.

The trouble with Rawls’s theory is that it aims to stay on the surface of things and very largely succeeds. Instead of digging into the metaphysical and epistemological questions that have preoccupied philosophers in the past, Rawls seeks to avoid them. Its goal is not truth but agreement, which he believes can be achieved through a systematic reconstruction of current moral beliefs. But which moral beliefs are allowed into consideration, and how is this decided? As a method in moral theory, reflective equilibrium has the fatal flaw of intuitionism. It has no way of addressing those who stand outside the charmed circle of people whose intuitions are viewed as relevant.

As a way of doing political theory it is prone to a corresponding failure of realism. The data that are used to construct the theory of justice are the moral intuitions of the liberal academy, but these are no longer widely shared in the larger society (if they ever were) and have little leverage on political practice. Anti-liberal forces such as ethnic nationalism and religious fundamentalism have come to shape much of contemporary political life. Yet, like Rawls, Nussbaum barely mentions this fact. She notes that just institutions of the kind envisioned in Rawls’s theory “do not come into being unless people want them, and they can cease to be if people stop wanting them, something that the demise of New Deal-style social democracy in the United States has shown all too clearly.” She does not ask how the rights and liberties she believes ought to be enshrined in law can survive when the larger political culture is indifferent or hostile to the values they express.

In a curious convergence liberal theory has given up on politics at a time when liberal values have become marginal in practice. Instead of trying to understand the forces that shape political life–as John Stuart Mill did in his writings on socialism and nationality, for example–contemporary liberal thinkers have constructed a legalistic edifice from which politics has been excluded. Nussbaum is aware that this rickety structure shuts out a great deal that is important, and in Frontiers of Justice she tries to let in some light. If she achieves less than she might it is because the giant shadow of Rawls stands in her way.