I'm sure that is the only time in the history of humankind

those two words have ever been spoken together.

I'm Angela Duckworth.

I'm Stephen Dubner.

And you're listening to no stupid questions.

Today on the show, why do people grind thirteenth?

I'm not saying your dentist is a crook,

but your dentist might be a crook.

Angela, we have discussed in the past on the show

the fact that you are not the world's best sleeper.

That's true.

And continues to be true.

You've also mentioned to me that you grind your teeth.

I've learned this is called bruxism.

And technically, there's both awake bruxism

and sleep bruxism.

Correct.

Are you an awake bruxist or an asleep bruxist

or both, perhaps?

I don't know how someone knows that there are a bruxer

in their sleep.

I mean, there are definitely times where I notice

...