So you got your PhD in economics from Harvard.

I know that you and your husband have eight children,

and you are stepmom to six more children from your husband's first marriage.

I'm guessing there are not many other Harvard-educated economists who have 14 children.

I don't know of any. Absence of evidence isn't evidence of absence children? I don't know of any. Absence of

evidence isn't evidence of absence, but I don't know of any. Catherine Pekolic is an economics

professor at the Catholic University of America. I asked about her main areas of research.

Education, schools, fertility, family formation. And what would you say you bring to those

topics that the median economists might not bring? I think I bring to the table a large number of

things that are outside of the field. And, you know, of course, I'd be disingenuous if I didn't add that we'll

have a lot of kids. And so that makes you think about things a little bit differently.

You might say that a lot of people have started to think differently about fertility and family

formation. For decades, the great fear among demographers and politicians and environmentalists was overpopulation.

They argued that the Earth's resources simply couldn't support 3 billion people,

certainly not 5 billion, or 8 billion, which is where we stand today.

That fear hasn't totally gone away, but it has been joined by a fear of the opposite, that

there are now too few babies being born.

Here's an astonishing fact.

The global fertility rate has fallen by more than half over the past 50 years.

Why?

The answer to that question is complicated, and any solution is even more so.

Today, on Freakonomics Radio, we began a three-part series about the great arc of human life.

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