Epistemic status: an attempt to model gossip, not based on research. confidant that this describes real dynamics, though there's room for refinement.

Gossip requires at least 3 parties - the Gossiper, the Target (who's being gossiped about), and the Recipient (who's being gossiped to).

The two basic questions we can ask about each party are:

1. How does gossip benefit them?
2. How does gossip harm them?

Suppose Alice gossips to Bob about Carol.

There are a few common ways of looking at this interaction.

1. Alice and Bob gossip because it's fun and interesting
2. Alice is gossiping to increase her own status or decrease Carol's status
3. Alice is gossiping to inform and benefit Bob
4. Whatever reason Alice is gossiping, she's actually hurting her status in the eyes of Bob and he will not trust her to protect his privacy.

The first one is a curiosity stopper; though true, it doesn't tell us much.

The other options also have truth to them, but none tell the whole story.

Harms and Benefits From Gossip

Here I'll explore a bunch of different gossip situations that either harm or benefit one of the parties, after that I'll explore what information can be gleaned from gossip, and what might be some good gossip norms.

The Gossiped

Harms

Gossip inherently breaches the privacy of the gossiped. When being gossiped about you have no control on what's being shared. Even if the gossiper has good intentions, they might share something which they didn't know they should have kept secret.

The typical case of gossip is when Carol did something bad, and Alice reveals that information to Bob. Now Bob might stay away from Carol or actively hurt her in some way (such as by further spreading the gossip).

Though I can think of some atypical cases.

If Carol just had something really good happen to her, like being accepted to a job she wanted, she might want to tell Bob herself, and would be upset if Alice already told him. 

This can also happen with a negative thing Carol meant to tell Bob about. Suppose Carol broke a promise to Bob. She can make it up to him in part just by being honest and telling him. But if Alice tells Bob before Carol gets to, Bob might accuse Carol of not telling him. Now Carol can only claim that she meant to tell him, but she lost the chance to show it.

Benefits

The less discussed case is gossip about positive traits. When Alice tells Bob how generous and happy to help Carol is, Bob comes to think better of Carol, and Carol benefits from it. 

That's useful if Bob didn't know, but if it's a positive trait, why would Bob need Alice to tell him, can't Carol tell him herself?

She can! Carol can tell Bob "If you need anything from me just ask, I'm always happy to help". But Bob may have doubts whether she is telling the truth. When Alice says Carol is generous it corroborates Carol's claim. 

There are also cases where it's harder for Carol to give Bob the information herself. Carol might not be able to tell Bob the extent of her virtue if she's expected to be modest about it. When self-promotion is taboo,  positive gossip is extra valuable.

The other interesting bit is that in the case of positive gossip, the more you "violate" others’ privacy (i.e. reveal details about them) the better it is for the gossiped! If Alice tells Bob stories of when Carol had been generous, Bob gets much more evidence and knows Alice isn't just repeating Carol's statement.

Okay, but can negative gossip benefit the target?

Yes!

• Simple case: Carol can benefit from negative gossip if people notice that the only bad things people have to say about her aren't that bad.
• Carol might have an embarrassing trait that, all else being equal, she would prefer others not to know about. Alice knows that, and informs Bob so he accommodates Carol. She would have preferred if Alice was able to change Bob's behavior without telling him. But even if that's possible, then Alice saved Carol the pain of maybe having to tell Bob herself. In addition, the lack of common knowledge between them might also be valuable to Carol.
• Negative gossip can be a chance for the recipient to protect the gossiped. If Alice says something false about Carol, Bob can correct her, and hopefully Alice will change her mind. If Alice didn't share the negative gossip no one would have corrected her.
• Gossip can keep incompatible people away from you. Suppose Bob is interested in a relationship with Carol but they don't know that they have a mutually incompatible trait, and they wouldn't discover that for a long time if they're not told. Even if that trait of Carol's is an embarrassing negative trait, she might benefit from Alice telling Bob about that if it saves her the trouble she would get from getting involved with him.
• And as we saw in the previous section, unbiased gossip makes all gossip more trustworthy, including positive gossip.

The Recipient

Harms

In theory, people aren't supposed to be harmed by getting information. In practice, it can happen. 

• Hearing gossip about someone can prejudice us in a wrong direction, or in the right direction, but too strongly.
• Someone can use gossip to foment FUD, which can harm the listener.
• Positive gossip might ruin your chance to hear the information from the person gossiped about. If something really good happened to Carol, Bob might prefer hearing it from her the first time, so he can have the initial surprise and excitement with her.

Benefits

The recipient gets more information which he can use however he likes.

There's a potential benefit in refusing to be negatively gossiped to — It might raise your status in the eyes of the gossiper, and in the eyes of others if the gossiper positively gossips about that to others (see meta-gossip section later). 

For example, if Alice was about to tell Bob some embarrassing thing about Carol, Bob might stop her and say "If she doesn't want me to know that then I don't want to know either". And in our happy virtuous world Alice would recognize that as the more virtuous act and respect Bob for that. 

But that seems like a negligible benefit that can even go the other way in some circles where the recipient's respect for others’ privacy won't be positively regarded.

For example, say Bob and Carol are together, and Carol is doing something without Bob's knowledge that Alice thinks he should know. Alice goes to tell Bob, and Bob stops her: "If she doesn't want me to know that then I don't want to know either". Alice concludes that Bob is a loser that won't demand what he deserves.

The Gossiper

In Blackmail Zvi writes:

Most gossip is designed to help the person gossiping. One earns points for good gossip. One builds allies, shows value, has fun, shares important information. It might harm or help third parties. In some cases, the motivation will be to hurt someone else, but that is one of many possible reasons. Most information people tell to other people is motivated by a desire to be helpful, even if that desire is for selfish ends.

Alice might want to harm Carol. She might want to help Carol. She might want to help Bob while either harming or also helping Carol. But she also might just care about what she gets from gossiping.

Now there's the question of whether gossiping helps her. There's a common saying that one should avoid gossiping as it shows others you can't be trusted. But that doesn't really square with how ingrained gossiping seems to be in us. If it was such a harmful habit would it really be so common? Wouldn't evolution do something about that?

It also doesn't seem to square with experience for many people. They gossiped a lot and it only strengthened their relationship with others.

It can't be one or the other, It's both - Gossip can both harm and benefit the gossiper. The interesting part is what makes the difference.

Harms

Let's see where the usual story is true.

Gossip is expected to be relevant, true, and in some way fair.

Everyone can recognize mean gossip. If Alice tells Bob all the embarrassing things she knows about Carol, that would be mean. And if Bob cares about that (rather than enjoying mean gossip about Carol) he will not think well of Alice and won't trust her to protect his privacy in the future.

Gossip needs to be justifiable. Not everyone needs to know Carol is an alcoholic. If Alice tells that to Bob without it being important enough to tell him, it would be a violation.

Benefits

A good gossiper can be an invaluable friend. If Alice is a good gossip, it will elevate her status and make Bob want to be good friends with her.

Good gossip compounds. As you provide better gossip, more people want to be your friend, which gives you more to gossip about.

As we saw, being gossiped about can also be beneficial. So being friends with a good gossiper isn't just good for receiving gossip, it also helps getting good gossip about you to spread.

A bad gossiper can hurt their reputation, while a good gossiper can turn themselves into an invaluable resource.

Another reason for engaging in gossip is seeking advice about someone. Alice had a rough situation with Carol, so she tells Bob about it to get his help. This might even embarrasses Alice and reduce her status, but she's willing to sacrifice status to get help. This is still a selfish motive, but very different from raising your status. 

Gossip and information

The object level purpose of gossip is to share information. The higher-level purpose depends on how it's interpreted. We explored what each party gains and loses from gossip. To get a complete picture, we need to explore what information can be gleaned from gossip.

Alice tells Bob that Carol is "Very generous". What can Bob learn from that about Carol?

Well, it depends.

Bob can weigh the claim against the quality of Alice's previous gossip. Did the things she said previously were true? If so, then Bob should generally trust her information.

This gives a reason why we'd want far more gossip than seems useful. When people gossip to us we learn the quality of their gossip even if the information they share isn't important, or already known to us.

Actually, especially if it's already known to us or we have an easy way to find out, cause then we can learn from that immediately.

If Alice told Bob something about Carol which Bob knows to be false, then Bob will trust Alice's gossip less in the future.

If Bob heard a lot of Alice's gossip and it has all been true, then how should he update on Alice's gossip about Carol?

Well...

Does Alice mostly gossip negatively or positively?

If Alice usually avoids negative gossip, then Bob can trust Alice when she says Carol is generous. But Bob cannot be confident about a lack of negative traits — Alice wouldn't tell him even if they existed. If Alice gossips freely about negative traits then Bob can be more confident there's nothing he should know that she didn't tell him.

Same thing if Alice told Bob something negative about Carol. If Alice never says good things then Bob can't tell if that bad trait is representative of Carol or not.

But the really interesting thing here, is that even the target of the gossip benefits from a norm of both negative and positive gossip!

If there's a norm against negative gossip, then I benefit less from positive gossip about me!

If I am a good person, then I want people to be honest about me so the people they talk to can find out how great I am and how little flaws I have.

But there's a balance — If there's too much negative gossip and not enough positive gossip, then I don't get the benefits, There's only lots of mutual harm.^[1]

So for Alice's gossip to be helpful, it needs to be true and unfiltered — or at least, reasonably filtered.

What are good gossip norms?

All in all, it seems to add up to normality. Some gossip can harm you, some benefits you. We should neither have a total policy against gossip nor a total policy in favor of it.

Gossip Is Hard

Before getting into specific norms, I should mention the difficulty of doing so.

People, at least the vast majority of them, don't get good at gossip because they read about it. It's an ability that either comes, or doesn't come, naturally.

I might be able to mention a few good norms, but they would still require a lot of implicit understanding of people and social situations.

Thus, the first rule of gossip is

Be Cautious

If you're not sure whether to share a bit of gossip, err on the side of not sharing it. You can ask the person you're with whether they think you should gossip about it without revealing details, but that's still a non-zero risk. If you're also not sure if that's a good idea, err on the side of not doing that either.

Playing the game of gossip badly will hurt you more than not playing it.

Respecting Preferences

A good starting place seems to be asking "Would the target approve of the gossip in retrospect if they knew it happened?". Phrased differently, "Would the target prefer the world in which the gossip happened or that one where it didn't?".

If the answer is yes, then we may gossip away. Otherwise there are two more caveats:

First, the gossip needs to be seen in context. A person might prefer a negative detail about him wouldn't be shared on its own, but if it's part of a full and honest gossip about them, it might be worth it to them and they would approve of it.

Second, you can't always accommodate people's preferences. The obvious case is when someone has a really awful trait which other people have the right to know even against their will. e.g, they're a serial killer. Of course they wouldn't want others to know, but that doesn't even go into the calculation.

A more subtle case is when you think someone's preferences are wrong. If they have a fear of the dark they might really not want people to know, but you think it's best if you tell someone. This is a difficult case, but I believe there are times where you should reveal information against someone's preference for their benefit. You must be cautious with that though, you can easily burn yourself.

Evenness

do both negative gossip and positive gossip. Best if you don't have a preference for one over the other. Just gossip honestly on what seems relevant.

Quantity and Importance

It doesn't have to be important though.

You can gossip a lot and on unimportant things - That's how people learn the quality of your gossip. If i don't have a lot of info on your gossiping then your gossip might be next to useless for me. You are judged more by the quality of your gossip than the quantity of your gossip.

Secondhand Gossip is Bad 

Secondhand gossip will almost always be less true and reliable, and the more hands it passes the less true and reliable it is.

Additionally, when someone gossips to you they usually expect it to stay with you. It's true that they already breached the person's privacy somewhat, but they expect it not to be further breached (of course, if it's an actual secret they shouldn't have even risked it).

If after all that you still think sharing secondhand gossip is important, always mention it's secondhand, and from whom (unless there's a good reason to hide the identity of the source).

• Bad: "Carol is a serial killer."
• Better: "David told me Carol is a serial killer."

Meta Gossip

How can we promote good gossip norms in a community? Or even before that, how can we know who to trust with regards to gossip? Why, more gossip!

We can meta-gossip about how other people gossip, how good are they at keeping secrets and protecting privacy.

To trust that Alice is keeping to the gossip norms, it's not sufficient for Bob to only observe how Alice is gossiping with him. She might be putting on a show of being discrete so Bob opens up to her and she can later go and gossip about it to Carol. If others gossip that Alice is a good gossip, then Bob can trust her more.

Meta-gossip is still constrained by the gossip norms. It should be honest, unbiased and relevant.

Gossip about gossip happens naturally, but not a lot. I think that's partially due to people not explicitly thinking much about gossip - they're just talking with people about other people, it's barely even a different mode of conversation. This, to me, also seems to be the reason why gossiping norms are so vague, and why many thing people say about gossip are confused or incomplete.

Why Does Gossip Have a Bad Name?

Writing this post and thinking deeply about gossip led me to think of more non-obvious benefits than harms, which made me more in favor of gossip than against it, and made this post fairly positive towards it. but still, gossip has a bad name, all the while still being practiced all the time by practically everyone.

I wonder what purpose this juxtaposition serves, since if it exists I expect it serve some purpose. Maybe It's a guardrail against gossip going wrong? A rule which is enforced only on the incompetent to deal with them? I'm not sure. But I do worry that, as was pointed out to me by a beta reader, this post is too positive towards gossip. I'd love to hear thoughts on this juxtaposition.

Conclusion

There's bad gossip and good gossip. Good gossip is a net benefit in a community, and is also a net benefit to most, and possibly all, individuals in a community. 

Good gossip doesn't just disincentivizes bad behavior, it also incentivizes good behavior through positive gossip. Neither positive nor negative gossip are as useful on their own as they are together.

Bad gossipers are likely to hurt their reputation, while good gossipers will become very popular - Both as a source of gossip, and as a way to spread helpful gossip about you.

A short incomplete list of good gossip norms:

1. Start by respecting people's preferences
2. Put the preferences in a wider context
3. Weigh their preferences against other considerations.
4. Be honest, avoid Deception.
5. Don't be biased between positive and negative gossiping.
6. You are judged more by the quality of your gossip than the quantity of your gossip. You don't need to worry about gossiping a lot - that's how people learn the value of your gossiping.
7. Don't spread secondhand gossip. If you break this rule, mention who that gossip comes from.
8. Use meta-gossip to maintain gossip norms and learn who to trust.

In a community with good gossiping norms most people will benefit from gossiping - Both short term and long term.

Thanks to lsusr and demp for commenting on drafts of this post.

1. ^{^}

   This is similar to the scenario Zvi illustrates in Blackmail, only much less extreme.