I was reading an interesting article on the rule of reciprocity from our Psychology Guide, Kendra Cherry. The article got me thinking about how this rule might affect friendships. Basically, speaking, the rule of reciprocity states that when someone does something for you, you'll feel obligated to do something for them.
Obligated. That's a bad word in friendships, because it means you're doing something just because you think you should. Like, you might think you'll look bad if you don't do this. Whatever you do is for your own benefit and not a genuine desire to help someone. That's never good for a friendship.
If you think about how many times you've done something for a friend (or more than likely, an acquaintance who isn't even quite a friend yet), you'll see how strong the rule of reciprocity can be. Note that the rule of reciprocity is the direct opposite of random acts of kindness, which are often done anonymously just because someone wanted to do something nice. With a random act of kindness, you often cannot pay it back. You might not even know who did something nice for you.
These are the very acts we need more of, because they inspire a genuine desire for good, rather than obligation that we don't entirely feel.