Since it’s graduation season, I’ve been thinking again about George Saunders’ wonderful little book Congratulations, by the Way, based on the commencement address he gave in 2013. And honestly? It still completely holds up.

Of all the advice he could have given graduating students, Saunders’ central message was surprisingly simple: Be kinder. Sooner.

What makes the book so powerful is that he doesn’t preach. He tells stories—funny, strange, human stories about mistakes, regrets, and misadventures. At one point, he recounts jumping buck naked into a lake in Indonesia full of monkey poop and becoming deathly ill for something like seven months.

Nope, he says, he doesn’t regret that.

What he does regret is this: In seventh grade, there was a girl at school who was teased and isolated. He didn’t join in. But he also didn’t step forward to defend her or befriend her.

I remember reading the book years ago and thinking: Of all the wisdom in the world, maybe kindness really is the big one.