Economists warn that policies to level the economic playing field come with a hefty price tag. But this so-called 'equality-efficiency trade-off' - has proven difficult to document. The data suggest, instead, that the extraordinary levels of economic inequality now experienced in many economies...

Some philosophers and social scientists have stressed the importance for good government of an altruistic citizenry that values the well being of one another. Others have emphasized the need for incentives that induce even the self interested to contribute to the public good. Implicitly most...