This is Planet Money from NPR.

I was talking the other day with Dean Carlin.

He is an economist who has studied why people donate money.

And as we were talking, he mentioned this sort of Econ 101 question that is useful in

thinking about this.

The question is, when we're far away from home and eating out, why do we leave a tip?

Why would you ever pay?

I don't live in this area.

I don't have to worry about this waiter, you know, hitting in my food the next time I come.

But of course, we do tip, even when we'll never be back again.

And Carlin says, we tip for a pretty straightforward reason.

If I don't pay, I feel like crap.

If I pay, I feel content with myself.

I was talking to Carlin about this because now is the time of year when we ask you for money.

You don't have to pay to listen, but a lot of people who listen to Planet Money do pay.

They donate to NPR, not because they have to, but because it makes them feel good.

So if you can spare a few bucks, please go to donate.npr.org slash Planet Money.

Thanks very much.

Hello?

Sam.

Hi.

How are you?

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