RAWLS AND INEQUALITY
A bit of background-setting is needed – I’ll keep it as brief as I can.
The question and any relevant answer clearly concern Rawls’ ‘difference principle’, which he defines as follows :
▻ DIFFERENCE PRINCIPLE DEFINED
'Social and economic inequalities are to be arranged so that they are ... to the greatest benefit of the least advantaged . . .' (Rawls, A Theory of Justice (Oxford: Oxford University Press, 1972), p. 83. From now on ‘TJ’.)
Or put another way and more specifically :
Assuming the framework of institutions required by equal liberty and fair equality of opportunity, the higher expectations of those better situated are just if and only if they work as part of a scheme which improves the expectations of the least advantaged members of society. (TJ :75.)
▻ THE LEAST ADVANTAGED DEFINED
Who are the ‘least advantaged’ ?
Here it seems impossible to avoid a certain arbitrariness. One possibility is to choose a particular social position, say that of the unskilled worker, and then to count as the least advantaged all those with the average income and wealth of this group, or less. The expectation of the lowest representative man is defined as the average taken over this whole class. Another alternative is a definition solely in terms of relative income and wealth with no reference to social position. Thus all persons with less than half of the median income and wealth may be taken as the least advantaged segment. This definition de pends only upon the lower half of the distribution and has the merit of focusing attention on the social distance between those who have least and the average citizen. Surely this gap is an essential feature of the situation of the less favored members of society. I suppose that either of these definitions, or some combination of them, will serve well enough. In any case we are to aggregate to some degree over the expectations of the worst off, and the figure to be selected on which to base these computations is to a certain extent ad hoc... It may turn out that a more exact definition of the least favored proves unnecessary. (TJ, 98.)
Two comments on this are (1) that it does not identify any least advantaged individual but only a social group or class : ‘the least favoured members of society’ are the reference point. And (2) that it is that it is purely economic in its focus, centred on the least advantaged in respect of income and wealth.
▻ WHY ACCEPT THE DIFFERENCE PRINCIPLE ?
The difference principle would be little worthy of discussion if it were merely an ad hoc principle jutting out of Rawls’ theory of justice. It needs defence if only on Rawls’ behalf. JEJ Altham explains the principle’s rationale neatly :
The principles of justice, in Rawls's view, are principles that would be agreed to in a position of equality by rational, mutually disinterested parties who know the general truths of social and economic theory, but are ignorant of all particular facts, including facts about their own aptitudes, preferences and future social positions. In agreeing on the difference principle, the parties are playing safe. Now if they are to play as safe as possible, it is not enough to agree that the representative man in the least advantaged group should have his expectations maximized, which is how Rawls puts the agreement. For within any group defined by the basic structure, there may still be wide variations in expectations. To select a representative man, it will be necessary to aggregate in some way the expectations of individuals in the group. The expectations of the represen tative man in the least advantaged group may thus be fairly high, while still leaving the very worst off in that group in appallingly miserable circumstances. In the original position, behind the veil of ignorance, no party to the contract can be sure that he will not turn out to be such an unrepresentative man, highly disadvantaged even by the standards of the least advantaged group. (JEJ Altham, ‘Rawls's Difference Principle’, Philosophy, Vol. 48, No. 183 (Jan., 1973), 76-7.)
▻ INEQUALITY WOULD ONLY BE JUSTIFIABLE …’
The quote misrepresents Rawls’ position. He does not say that ‘Inequality would only be justifiable if the gains to the rich would also improve the gain of the poor’. This is an anaemic version of what he says, which is that inequalities, if they arise, ‘are to be arranged so that they are ‘to the greatest benefit of the least advantaged’. Mere gain cannot be equated with ‘greatest benefit’.
If there are inequalities (and Rawls does not say that they are inevitable) they can only be justified if (a) equality) or (b) all other inequalities (patterns of inequality) would result in less benefit to the least advantaged. If such inequalities as might arise do not fulfil these conditions then redistribution – redistributive taxation – would be justified in order to create equality or a different pattern of inequality, whichever is to the maximum benefit of the least advantaged.
Not only does Rawls not say that inequalities are inevitable or that such inequalities as do arise are to be to the greatest benefit of the least advantaged, he also sets an outer limit to the level of inequality
Although in theory the difference principle permits indefinitely large inequalities in return for small gains to the less favoured, the spread of income and wealth should not be excessive in practice, given the requisite background institutions' (TJ, 536).
This would also justify redistribution.
In saying what would justify what, I am talking within Rawls' theory. My own views about his theory of justice are not involved.