Q: When do you have to reciprocate a party invitation? I always thought that if it’s a small event in someone’s home, it’s important to reciprocate. What about a payback for having been included in a ...

Non-human animals consider the value of previously received help when deciding whether to help a social partner, according to a new study in rats. Until now, it was unclear whether animals other than ...

Reciprocity (give-and-take exchange) is essential for successful human interactions. Feeling motivated to return a favor (and feeling owed for a favor) drives social behavior, personal interaction, ...

An etiquette expert weighs in. You've written your list, you've checked it twice. The holidays are officially here, and you're working to ensure that every last soul on your scroll (or named in your ...