income inequality

David Lay Williams, professor of political science at DePaul University, talks about his book, "The Greatest of All Plagues: How Economic Inequality Shaped Political Thought from Plato to Marx."

David Lay Williams, professor of political science at DePaul University, talks about his book, "The Greatest of All Plagues: How Economic Inequality Shaped Political Thought from Plato to Marx."

The gap between the richest and the poorest U.S. households is now the largest it's been in the past 50 years, the U.S. Census Bureau says.