In a few of my early posts on this blog, I claimed that libertarianism is compatible with a commitment to some kind of social justice. But I was deliberately vague about just what a commitment to “social justice” entails.
In this post, I want to survey a few ways in which the idea of social justice could be made clearer. I'm not going to defend these approaches, and my presentation of them will of necessity be overly-simplified. But I'm hoping the ideas here can provide a framework for future discussion.
Before I get started, though, I want to clarify one very important issue. Some of my libertarian economist friends have exprsesed a deep skepticism about the idea of social justice. (See, for instance, the comments thread for this post at Coordination Problem) They worry, for instance, that government agents will lack the knowledge or the incentives necessary to implement the philosopher's preferred theory of social justice. Or they worry that concerns about social justice are based on a misunderstanding about how markets work.
Let me be clear. In advocating social justice, I am not challenging any of the empirical claims that economists make about the virtues of markets and the pathologies of government. In fact, I think those claims are mostly true, and deeply important. But they are important for thinking about how we should try to realize social justice, not for thinking about what social justice is or whether it even exists. Economic science is about means, not ends. It can tell us how to achieve our goals, but not what our goals should be. It can tell us which policies "work," but not what it means for a policy to "work." The specification of the criteria by which social processes and outcomes are to be judged is the job of moral philosophy. And it is a job that is largely, if not entirely, independent of the empirical concerns raised by my economist friends.
So, with that clarification out of the way, let me say a little bit about two ways in which a concern for social justice might be fleshed out. Notice that I am leaving strict egalitarianism – understood as the idea that people out to be made equal with respect to certain outcomes such as happiness or wealth – off this list. There are two reasons for this. First, I don't think it's plausible that this kind of egalitarianism is really compatible with libertarianism. Second, contrary to the impression that many non-philosophers seem to have, this kind of egalitarianism has relatively few adherents, even among left-leaning philosophers. (See, for a nice discussion of the kind of equality philosophers do find attractive, the Stanford Encyclopedia of Philosophy entry on Equality)
Prioritarianism – This view is most closely associated with Derek Parfit. Prioritarianism is usually understood as a kind of welfarist consequentialism. It is, in other words, a view that determines the goodness or badness of an outcome by looking at the aggregate welfare of the persons affected by the outcome, and defines right action as that which produces maximally good outcomes. What distinguishes prioritarianism from other forms of consequentialism, however, is that it gives extra "weight" to increases in welfare for worse-off individuals. So, all else being equal, an improvement to the welfare of someone who is poor, disabled, and unhappy, is to be preferred to an improvement to the welfare of someone who is already relatively well-off. And not merely for reasons of diminishing marginal utility. See here and here for more. Note also the similarity with the Catholic idea of a "preferential option for the poor," especially as exprsesed in "Economic Justice for All," a letter from the US Catholic Bishops in 1986: "The obligation to provide justice for all means that the poor have the single most urgent economic claim on the conscience of the nation."
Sufficientarianism – Prioritarianism focuses on improving the condition of the worse-off. As such, it is focused on correcting relative disadvantages. But relative disadvantages might exist in a society in which no one is absolutely disadvantaged. Consider a island community in which everyone enjoys material and social comforts equivalent to those available to an American billionaire, but some people are twice or three times as well off. In such a society, we might not think that relative disadvantages have any moral significance at all. Sufficientarianism, a view most closely associated with Harry Frankfurt, is able to accomodate this view by holding that morality requires us only to ensure that people have enough. "Enough" can be defined in terms of a certain level of resources, or primary goods, or utility, or any number of other things. And one can have enough even if others have much more than enough. Again, see here and here for more.
This list is far from exhaustive. A more thorough discussion would include Rawls' application of the difference principle to the basic structure of society, and Richard Arneson's idea of equal opportunity for welfare. Moreover, none of these ideas seem defensible to me as an account of the whole of morality. Prioritarianism might be a good interpretation of an important part of morality – the part that concerns our duties to the less fortunate. But surely there is more to morality than this. For instance, any adequate account of morality will probably need to incorporate some idea of personal responsibility, so that perhaps our political obligations to the poor are in large part dependent on the extent their poverty is the result of brute luck and not bad choices.
Furthermore, in thinking about what these views entail for public policy, it's worth keeping in mind the points Jason has made here and here. The fact that a good or just society is one in which everyone has access to sufficient resources does not mean that we should want politicians to do whatever they believe (or believe that they can convince us they believe) will ensure that this happens. If the libertarian economists are right, then politicians will do a worse job at achieving this outcome than we might hope, and markets will do a better job than we might think.
But that's not the issue here. The issue I'm concerned with isn't how we should try to achieve social justice, it's how we should understand what social justice is. And that is a philosophical question, not an economic one.
Philosophy can tell us what we should be aiming for, but not how to get there. Economics can tell us how to get where we want to go, but not where we should be trying to end up. Neither economics nor philosophy by itself can tell us what our public policies ought to look like.