Inequality is part and parcel of our lives. What degree of inequality we find acceptable or unacceptable informs the foundational values of our societies, and shapes our political and economic structures. Yet until recently the study of economic inequality (unlike poverty) was considered by economists as a problem not worth examining. That has changed. With the dramatic increase in the concentration of wealth in the hands of a few, inequality has become recognised by all shades of political opinion as a potential threat to economic growth and the functioning of society and democracy. In...