How just or unjust is a particular society, or indeed, the international realm? To answer this question, we need a metric with which to evaluate the moral worth (the justness) of social arrangements. Two approaches to measuring justice have emerged in the recent literature, each focusing on a particular metric: one on primary goods, the other on capabilities. The former approach, pioneered by John Rawls, holds that principles of justice should be concerned with the distribution of particular social goods or resources (for example, liberties, opportunities, income, and wealth) among persons; the latter, pioneered by Amartya Sen and Martha Nussbaum, holds that principles of justice should be concerned with the distribution of capabilities—namely, of substantive freedoms to achieve particular “functionings” (for example, being nourished, educated, healthy). Which approach should we favor?
In this rich collection, Harry Brighouse and Ingrid Robeyns bring together distinguished philosophers and political theorists to debate the virtues and vices of these competing metrics of justice. The first part of the book focuses on the fundamental properties of the two metrics from a theoretical perspective; the second part looks at how well each of them fares in addressing applied ethical problems, including justice in health, gender justice, and justice for children. The collection is then brought to a close with an essay by Amartya Sen.
This is an outstanding collection—well organized, interesting, and informative. All the essays are of high academic quality, and the collection as a whole fully achieves its aim: advancing our understanding of primary goods and capabilities, without necessarily declaring one superior to the other (p. 11).
Given the limited space at my disposal, I cannot comment on all the aspects of the book that deserve attention. I will therefore focus on one of its core messages, expressed explicitly or implicitly in a number of essays, namely that instead of being “competing” approaches to justice, the primary goods and capabilities metrics have much in common, and much to learn from each other. The insight behind this suggestion is easy to grasp. On the one hand, a primary goods metric seems defective because of its insensitivity to people's different abilities to convert goods into “functionings.” Plainly, an able-bodied and a disabled person with the same resources are unlikely to be equally well-off. On the other hand, capability-based metrics are often (although not always, think of Martha Nussbaum's work) too vaguely defined, lacking a full index of those functionings to which access is necessary for a decent life.
In light of this, advocates of primary goods should learn from capability theorists to make their metrics more sensitive to interpersonal differences, as discussed, for instance, in the essay by Thomas Pogge. Capability theorists, by contrast, should draw on the insights of advocates of primary goods to develop an index of capabilities. There may indeed be a parallelism between what makes certain social goods particularly valuable and what makes certain capabilities important (see Harry Brighouse and Elaine Unterhalter's essay).
The similarity, or at least complementarity, between the two approaches is further confirmed in an essay by Norman Daniels, who claims that, at least as far as justice in health is concerned, the conceptual spaces covered by a capabilities approach and by a nuanced primary goods approach virtually coincide. In a similar vein, Sen himself emphasizes that if there are differences between resourcist and capability-based views, these only concern one aspect of a theory of justice. “There is no claim,” he writes, “that the capability perspective can take over the work that other parts of Rawlsian theory also demand, particularly the special status of liberty and the demands of procedural fairness” (p. 242). In Sen's view, whether we should adopt the primary goods or capabilities approach only matters at the level of comparing persons' overall advantages, which is what Rawls's difference principle is concerned with.
If these observations are correct, however, one might wonder to what extent there is a genuine disagreement between resourcist and capability theorists. If there is so much that they have in common, and so much that they can learn from one another, is the contrast perhaps overstated? A possible way of further testing whether these approaches differ, and to what extent, might be to consider their implications for the measurement of justice across different societies. Is one approach better placed than the other to measure justice against the background of cultural pluralism characterizing the global arena? Is one less informationally demanding than the other, and therefore more likely to be workable when measurements are extremely complex, extending over a wide range of people and communities? Even though none of the essays in this book directly tackles these questions, they could certainly constitute a fruitful area for future research.
That said, Measuring Justice remains an excellent collection, which importantly contributes to deepening our understanding of the primary goods and capability approaches, and provides valuable insights for both political theorists and practitioners.
