I’m reading Martha Nussbaum’s Frontiers of Justice, which is an expanded version of her 2003 Tanner Lectures. In it, Nussbaum develops and applies her “capability approach” to social and political justice in three areas that traditional moral theories have often ignored: duties toward the disabled, foreigners, and nonhuman animals.
A major part of Nussbaum’s project is criticizing the social contract tradition, which, she argues, is incapable of dealing with these three issues. In her view, this is because most social contract theories (including that of John Rawls, whom Nussbaum considers to be the best exemplar of this tradition) are built in such a way as to exclude the claims of the disabled, the foreigner, and the nonhuman animal by definition.
In a typical social contract theory, principles of justice are derived by stripping away irrelevant features of actually existing human societies and asking what principles would be agreed to in a hypothetical contract arrived at by rational, self-interested persons of roughly equal bargaining power, physical strength, intellectual ability, etc. Nussbaum notes that some earlier forms of social contract theory (e.g., Locke) are impure or hybrid varieties because they incorporate elements of an earlier natural law tradition–for instance, the idea that each person has an innate moral dignity that entitles them to certain treatment. But as we get further away from that tradition, the features of the social contract more closely approximate an agreement between rational, self-interested agents without any prior moral constraints.
The reason social contract theories can’t adequately account for her three anomalous cases, Nussbaum thinks, is that the principles of justice they come up with are, by definition, those that would be appropriate for “normal” adults–i.e., people who are roughly equal in physical and intellectual capability. This is for the very simple reason that the parties to the social contract are assumed to be such normal adults (even in Rawls’s rarefied “original position”) and the principles they agree on are those they would choose to protect their own interests. Thus, the principles of the social contract can’t adequately account for or protect the interests of those who fall short of this kind of rough equality (e.g., the disabled or nonhuman animals). In fact, many social contract theorists explicitly deny that we have direct duties of justice to such “marginal cases.” We may care for them, out of sentiment or a sense of benevolence, but they are not owed anything as a strict matter of justice. (Although it’s not one of Nussbaum’s focuses, it seems that children would also fall beyond the pale for similar reasons.)
Most of Nussbaum’s book is aimed at showing how her capability approach–which, as I understand it, is kind of an updated Aristotelianism–can more adequately deal with these borderline cases than traditional theories, particularly social contract ones. I’m especially interested to see how she applies it to the case of nonhuman animals.