Making friends as an adult is hard, especially when people go around saying #NoNewFriends. And when you ask two people how they became pals, they often say, “We just clicked.” What does that even mean?!

Luckily science has a more concrete answer. One of the keys to making new friends is being vulnerable. We think people will be impressed by our amazing accomplishments and hobbies, but as this video from The School of Life explains, we tend to get close with others when we really open up. That often means sharing your insecurities without worrying how the other person will react. It’s a scary prospect, but you could end up with a new bestie.

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