Thousands of years before the modern era, great thinkers were theorizing about economic inequality. Unequal conditions were a focus of both Plato and Jesus, just as it was for later thinkers like Hobbes, Rousseau and Marx.

David Lay Williams is a professor of political science at DePaul University. His new book, “The Greatest of All Plagues: How Economic Inequality Shaped Political Thought from Plato to Marx,” traces some 2,500 years of intellectual history about inequality, drawing surprising new lessons from some of the foremost figures in the Western canon. In this conversation with host Steven Durlauf, Williams discusses his findings and what we can still learn from these world-historic thinkers.