“Inequality of what?” This question is answered, either implicitly or explicitly by anyone discussing inequality. Because data on income are relatively easy to obtain, the discussion of inequality is often reduced to considering income alone. But there are various kinds of inequality that can be of interest to Christian ethics and the wider moral debate. For instance, questions of unequal access to the internet and telecommunications have gained prominence as these forms of technology are seen as important vehicles for social participation. Other kinds of inequality related to wealth, political influence, education, or healthcare bear some relation to income-based disparity, but they are distinct realities.

Understanding inequality – and equality – becomes more complicated when more than one good is considered. Can equality of political participation be guaranteed, say, when income inequality is severe? Are we interested in examining the level of inequality of a few items (like income, political power, internet usage, ice-cream consumption), or in establishing equality of some less tangible “thing,” like social participation, or moral worth, or dignity? Philosophers and social scientists have contributed various other “currencies” in which inequality (and equality) can be considered: utility, opportunity resources, “primary goods,” “human capability,” “basic needs,” and so on.

Treatments of how inequality has been understood by political philosophers – including how they answer the question, “Inequality of what?”, and its relative, “Equality of what?” – will lay important groundwork.