Bridging Inequality of Opportunity, Sufficientarianism, and Limitarianism: A Framework for Assessing Unfair Inequality

Imagine that you are a policymaker and that one of your goals is to achieve a fair society. Given the complexity of what fairness might mean, one possible approach as a first step may be to use a measure of inequality of income distribution to compute how equitable society is.

The Gini index, for example, is one of the most widely used measures of inequality to obtain a numerical value of equity in the distribution of a country’s outcome. The Gini index varies between 0 (perfect equality) of outcomes and 1 (perfect inequality). A policymaker who cares about fairness will tend to prefer a distribution that generates values as close to 0 as possible. However, the index is 0 when all incomes are perfectly the same for all and equal to the mean. So, when we apply this index, it is as if we were comparing an empirical distribution of incomes to a hypothetical one where all incomes are equal. Should we then consider the latter as the normative reference distribution? Or, posed differently, should our society aspire to this distributional model? It seems logical to think that such a solution is rather extreme, even impossible to achieve (...)