Elinor Ostrom, a political scientist who won a Nobel Prize in economics in 2009, showed how ranchers, fishermen and others had devised clever ways to cooperate, without appealing to government, and to avoid the tragedy of the commons, which is the overexploitation of shared resources. One way they built the necessary trust was through what Ostrom called “cheap talk,” which is simple communication. “More cooperation occurs than predicted, ‘cheap talk’ increases cooperation, and subjects invest in sanctioning free-riders,” Ostrom wrote in her Nobel lecture.