No matter how skeptical one is of the authority of “experts,” it’s hard to avoid paying at least some attention to the people who award the Nobel prize — especially when they give one to someone who tends to support some things one tended to believe already. So it is in the case of Thomas Sargent, the New York University professor who was announced Monday as a winner of the Nobel in economics. An interview of Professor Sargent by the Minneapolis Fed in August 2010 summed up some of his contributions succinctly: “policymakers can’t manipulate the economy by systematically ‘tricking’...