No sword bites so fiercly as an evil tongue? Gossip wrecks reputation, but enhances cooperation

Social norms in general, and norms of cooperation in particular, are the cement of all human societies. For the difficult problems of the maintenance and enforcement of social norms and of cooperation, humans have developed surprisingly complex solutions. Reputation mechanisms and gossip are certainly among the compound informal solutions. According to common wisdom, gossip channels mainly negative and often fictitious information.