AMINATOU SOW: Hi. We are Ann Friedman and Aminatou Sow, and we are the authors of the book Big Friendship, as well as the hosts of the podcast Call Your Girlfriend.

HZ: And at some point between 2009, when they met and befriended each other, and 2013, when Ann used it in an article in New York Magazine, Aminatou and Ann coined the term Shine Theory.

ANN FRIEDMAN: I think this is just something that, you know, you probably said to me first, “I don't shine if you don't shine.” And then it became a thing we said frequently to each other and to other friends.

AMINATOU SOW: I will confess that it is the lyric from the Killers album that I just enjoyed a lot.