The Index Problem

The difference principle is vulnerable to a number of powerful objections. Some of these objections focus on the principle’s structure, and, in particular, on the implication

that we ought to provide a very small benefit to the least advantaged rather than to provide a much larger benefit to other individuals. A second set of objections

challenge the principle’s use of social primary goods, and, in particular, on the idea that we ought to determine an individual’s entitlements by reference to this metric. I shall

not press these objections now, in part because I develop objections of this kind in the next chapter. Instead, I offer an alternative objection that focuses on the difference

principle’s reliance upon an index of social primary goods.

The difference principle governs the distribution of an index of social primary

goods, which, as I have presented it, is comprised of a variety of goods, including income and wealth, advantaged social positions, job complexity and variety, and

discretionary time. On this basis, proponents of the difference principle sanction the rejection of a detailed division of labour as well as advocate the introduction of

working time directives or other policies that have similar effects. The reason for this, they contend, is that these interventions in the job market clearly enhance the position

of the least advantaged, measured in terms of an index of social primary goods.

A first objection to the difference principle challenges the grounds upon which

its proponents conclude that certain arrangements and distributions of work are unjust. To illustrate this worry, it is helpful to return to Arnold’s claim that it is better to forgo

a small increase in wages in order to have a job that scores much more highly in terms of other social primary goods. Against this, we may ask: why is Arnold entitled to draw

this conclusion? After all, he cannot rely upon a claim about what is objectively better for individuals, since claims of this kind are inconsistent with the liberal principle of

legitimacy, nor can he rely upon individuals’ preferences, since Rawlsians explicitly reject preference-satisfaction as an appropriate aim of justice.

I want, though, to focus my attention on a more politically significant objection to the difference principle. Though its proponents maintain that is clear which

arrangements and distributions of work we ought to reject as unjust, it is much less clear which arrangements and distributions of work we ought to accept as just. This is a

consequence of the index problem.110 _{The index problem arises because the difference}

principle requires us to make judgments concerning the relative weightings of distinct

social primary goods.111 _{To illustrate the problem, let’s consider a policy that increases}

the amount of discretionary time enjoyed by the least advantaged, but only by reducing

their level of income and wealth. Putting aside my earlier reservations, when the increase in discretionary time is particularly large, and the decrease in income and

110 _{Richard Arneson, ‘Primary Goods Reconsidered’, Noûs, 24 (1990b), 429-54.}

111 _{Ronald Dworkin similarly notes that the principle ‘is not sufficiently fine-tuned’ and that there is a} ‘degree of arbitrariness in the choice of any description of the worst-off group’. See Dworkin, Sovereign Virtue, 113.

wealth is particularly small, it may be clear that the difference principle justifies this policy. However, when this is not the case, it is not clear whether the policy advances

or reduces the position of the least advantaged. Accordingly, it is not clear whether the difference principle justifies this policy. This lack of clarity in the recommendations

that the difference principle originates from the necessity of ‘judging complex trade- offs between different elements of the bundle of social primary goods’.112

The index problem cuts deeper than it may first appear. The point is not merely that there is an epistemic difficulty in determining who the least advantaged are

and how best to improve their situation. Perhaps this problem could be overcome by the use of averaging, say. Rather, as Arneson points out, the point is that ‘Even if the

agency responsible for implementing [the difference principle] had complete knowledge of all pertinent information, she still would not know how to arrange

institutions to satisfy a primary goods standard, in the absence of an index’.113 _{At the}

heart of the index problem, therefore, is the claim that the difference principle is

insufficiently fine-tuned to be able to yield helpful institutional recommendations in a range of cases. Given how the justness of so many work-related policies depends upon

judgments concerning the relative weightings of distinct social primary goods, this problem is a particularly pressing one.114

There are three ways in which a defender of the difference principle may respond to the index problem. First, we may stipulate the relative weightings of distinct

social primary goods. For example, we could stipulate that an increase in discretionary

112 _{O’Neill, ‘Three Rawlsian Routes Towards Economic Democracy’, 52.} 113 _{Arneson, ‘Primary Goods Reconsidered’, 446.}

114 _{Rawls concedes that in these cases ‘we admittedly rely upon intuitive estimates. But this cannot be} avoided entirely’. See Rawls, A Theory of Justice, 80. However, it is not clear why he believes this to be a satisfactory response.

time from 30 hours a week to 35 hours a week is equivalent to an increase in annual salary from £25,000 to £27,000. This approach is unsatisfactory. This is because it risks

either being arbitrary or violating the demands of anti-perfectionism. If there is no argument in defence the weightings, then the stipulations are arbitrary, and hence lack

a justification. If we arrive at the weightings by appeal to an account of well-being, then the justification will be one that is reasonably rejected by certain individuals, and

hence results in an abandonment of anti-perfectionism.

O’Neill suggests a second response. He claims that we can overcome the index

problem ‘through the deliberations of democratic processes at the legislative stage of government’.115 _{That is, democracy provides our answer. The problem with this}

solution, however, is that it conflates justiceand legitimacy. Whilst it may be legitimate to implement a democratically-mandated policy, it does not follow that this policy is

just. Accordingly, an appeal to democracy cannot help us to answer the question of what justice demands. In so far as we are interested in just, rather than legitimate,

arrangements and distributions of work, therefore, this response is unhelpful. Moreover, justice as fairness aims to give guidance to each individual about how to

exercise her political influence. The theory would abrogate its responsibility to offer this guidance if it were to say nothing other than that the just policy is one that arises

from a democratic process.

In reply, a proponent of the difference principle could maintain that there is no

single just outcome and, perhaps, that a range of policies that could arise from a democratic process are all just.116 _{If this were the case, justice as fairness would not}

abrogate its responsibility to offer guidance to each individual, since all policies

115 _{O’Neill, ‘Three Rawlsian Routes Towards Economic Democracy’, 52; and Hockett and Risse,} ‘Primary Goods Revisited’.

(perhaps within a given range) qualify as just. This is the third response. The problem with this response is that we should not think of these kinds of disagreements in this

way. When two individuals debate the justness of a given policy, each thinks that the other is wrong. The present response cannot explain this. On this view, debates about

the justness of a given policy are like debates about the best flavour of ice-cream, where both could be correct. This cannot be right.

In summary: even if the difference principle could overcome my initial worry and therefore plausibly identify certain ways in which arrangements and distributions

of work can be unjust, the principle is insufficiently fine-tuned to be able to help us determine which social institutions we should accept as just. Moreover, it is not clear

how we can overcome this index problem in a principled and plausible way.