Why am I doing this?

I'm Angela Duckworth.

I'm Stephen Dubner.

And you're listening to No Stupid Questions.

Today on the show, how do you know when it's time to quit?

I love to gamble. I've lost $100,000 a last week.

Also, why is it so hard to predict success?

I'm sorry to say this, but your little boy is doomed.

He ate the marshmallow and he's going to be an idiot.

Angela Duckworth, my question today could be summarized as grit versus quit.

Grit.

What's that?

That's the answer.

All right.

Never mind then.

Let me explain, though.

So if you believe even a little bit in the sunk cost fallacy, the idea that it's bad to throw good money after bad or good time or any other resource after bad, then you also have to believe

it's a good idea to quit things more often than a lot of people are willing to quit. But we've been

preached to for decades, maybe centuries, that quitting is a moral failure. A quitter never wins

and a winner never quits and all that. But at Freakonomics, we've actually argued for the

upside of quitting. In fact, one of the very first radio shows we made 10 years ago was called

the upside of quitting. And we argue that for every hour or dollar or brain cell, you spend

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