Halfway through the 1800s, someone named Cecil B. Hartley wrote a guide titled The Gentlemen's Book of Etiquette and Manual of Politeness, which offers instruction on everything from conversation to dress to table manners to manly exercises. On the topic of gossip, Hartley advises readers to shun the practice outright, deeming it "detestable" in a woman and "utterly despicable" in a man.

His sentiment was neither new nor dated. From the Bible, which declares that a "gossip betrays a confidence, but a trustworthy person keeps a secret," to modern author and etiquette columnist Mary Mitchell, who encourages people to avoid spreading stories that can both hurt and harm, centuries of collective wisdom tends to support Hartley's position that gossip is bad. In short, it's a negative force that tears people down and pulls cultures apart.

"One of the key reasons that people behave as well as they do in groups, and that cooperation is sustainable instead of just rampant, capricious behavior is that people are concerned others will find out what they did, and that this discovery will undermine their opportunity to interact with others in future cooperative endeavors."

Despite this well-established understanding, however, some social scientists in California disagree. Gossip, they suggest, can be good. Necessary, even.

In a new study titled "Gossip and Ostracism Promote Cooperation in Groups" and published online by the journal Psychological Science, researchers from Stanford and the University of California-Berkeley argue that a healthy society allows its members to talk behind each other's backs as a means of self-regulation. If one member happens to be exploiting the hard work of those around him or somehow damaging the larger whole for his own personal gain, clandestine chatter and his subsequent expulsion from the chemistry club, basketball team, or nomadic tribe can help restore equality. Gossip, in other words, can both prevent and punish freeloading.

"One of the key reasons that people behave as well as they do in groups, and that cooperation is sustainable instead of just rampant, capricious behavior," the study's co-author and an associate professor of Sociology at Stanford, Robb Wille, told me, "is that people are concerned others will find out what they did, and that this discovery will undermine their opportunity to interact with others in future cooperative endeavors."

Makes sense, doesn't it? If you act selfishly, you get kicked out. And while gossip can sometimes carry connotations of malicious rumors or unverified hearsay or trivial nitpicking, Willer says in this case his team employed the boring yet precise definition of "reputational information sharing," which he explains falls under a "pro-social" subset of gossip.

For the study, Willer and his fellow researchers enlisted over 200 participants to play a public-goods exercise, whereby individuals were given a set amount of money and placed in multiple groups of four. Participants then decided how much of this money to keep for themselves and how much to donate to the group—a total researchers would then double and distribute evenly amongst the four members. In subsequent rounds, participants left messages for future groups telling them which individuals were least likely to share, and researchers granted groups the authority to exclude these particular participants.

Results showed that when researchers introduced gossip and ostracism into the mix, selfish participants began to change their ways and contribute to the greater good. While they didn't become saints, they did conform to the cooperative behavior of others. The ability to gossip, the experiment concluded, therefore had the power to deter, protect, and reform.

"A lot of this work focuses on the role of reputation," Willer says. "While you might be able to free-ride in one group and never see the members of that group again, if they can communicate to other people that really reduces your incentive to do so."

If all this sounds familiar, that's because, like most things, the ancient Greeks did it first. During the 5th century B.C.E., once a year to safeguard their democracy, citizens of Athens could exile someone they feared had become too powerful or possessed tyrannical tendencies. Indeed, our word ostracism comes from the Greek ostrakon, which was a shard of pottery that citizens used to scratch the name of the person they wished banished. If at least 6,000 votes were cast for one man in particular, and that man received the most votes in total, officials would eject him from the city for 10 years. There was, of course, plenty of room for abuse and eliminating one's political opponent, but if Willer and his colleagues are right, this general idea is still being practiced today by functional groups all across America.

What the study doesn't address, however, is if the group's agreed-upon good is considered a wrong by many on the outside. Like, say, the Klu Klux Klan or Nazi Germany. In situations like these, it seems keeping members in line through gossip and ostracism might not be the best of outcomes.

Plus, with idle chatter moving online and, at times, assuming the form of anonymous bullying or smear campaigns involving little to no consequences for the gossipers, things are a bit more complicated. Then again, social media can also serve as a ubiquitous surveillance mechanism to keep people accountable in the most productive of ways, too.

So how does one go about navigating this new frontier for gossip? Perhaps Hartley's guide, published over a century and a half ago, is worth another visit: