Why Cities Rock: Could it be that cities are “our greatest invention” – that, despite their reputation as soot-spewing engines of doom, they in fact make us richer, smarter, happier and (gulp) greener? This week’s Freakonomics Radio podcast is a bit unusual in that, instead of featuring a variety of guests, it has only one. But I think you’ll understand why once you’ve listened to it. The guest is Ed Glaeser, author of the compelling and provocative (and empirical!) new book Triumph of the City: How Our Greatest Invention Makes Us Richer, Smarter, Greener, Healthier, and Happier.

Plainly put, Glaeser’s ideas are so large and bountiful that they required a podcast of their own. (You can download/subscribe at iTunes, get the RSS feed, read the transcript, or listen via the box above.)

Glaeser is an economist at Harvard whose research touches on everything from obesity and crime to innovation and urban policy. Here’s a 2006 Times Magazine profile of him by Jon Gertner; here are Glaeser’s posts from the Economix blog.

Glaeser previewed his book with a guest post on this blog a few days ago. The podcast delivers the full monty. For instance, Glaeser’s argument that cities are in fact greener than the countryside:

We’re a destructive species; it’s one of our defining characteristics, right? We make a big mess when we’re around stuff. And if you love nature, stay away from it, right? We’re much more likely to harm nature as the road did when we live surrounded by the woods than if we live in tall urban apartments by ourselves. Now, there’s a statistical partner to that, which is that together with Matthew Kahn, I’ve assembled data on carbon emissions associated with living in different parts of the country. And there are two facts, which I think are important, to come out of that. One of which is that people who live in cities do tend to emit significantly less carbon than people who live in the country, and this is controlling for income and controlling for family size. That’s coming mainly from driving, from the fact that there’s just a lot fewer carbon emissions associated with dense living. It’s not just the move to public transportation; it’s also the drivers within cities — they’re just driving much shorter distances. And then, of course, it’s because of much smaller homes. The higher price of urban space means that people are living in smaller homes, even with the same family size. And that leads to lower electricity usage, lower home heating usage — and those are the facts that I think make cities seem, at least to my eyes, significantly greener.

Here’s Glaeser on one of the many ways that the federal government has long upheld anti-city policies:

The home-mortgage interest deduction essentially acts as a push away from urban apartments and into suburban homes. And let’s just go through this — more than 85 percent of single-family detached houses in this country are owner occupied. More than 85 percent of multi-unit dwellings are rented. There’s a good reason for this. If you rent out single-family detached housing, they depreciate on average, more than 1 percent a year, according to some studies. And that’s quite easy to understand: renters don’t do the maintenance that homeowners do, to keep taking care of their homes. On the other hand, anyone who has ever dealt with a co-op board knows that having a ton of owners under a single roof can be like herding cats, so there’s a good reason why larger buildings are essentially rented. Well, if high-density dwellings are typically rented and low-density dwellings are typically owned, then if you’re going to have a huge public push where hundreds of billions of dollars are going to be thrown at promoting home ownership, you’re basically telling cities to go drop dead, right? You’re basically pushing people out of urban apartments and into suburban homes, and I think that’s a mistake. And I’m glad that President Obama‘s budget came out favoring, at least, a reduction and a cap of the home-mortgage interest deduction.

And why cities produce better restaurants than they do schools:

Certainly for anyone who’s a parent, like myself, the suburban school districts offer huge enticement to leave cities. And this is really a question of how we’ve decided to structure our schools. So I want you to just imagine, if, for example, instead of having a New York restaurant scene that was dominated by private entrepreneurs, who competed wildly with each other, trying to come up with new, new things and, you know, the bad restaurants collapsed, the good restaurants go on to cooking show fame, and you have these powerful forces of competition and innovation working. Imagine instead if there was a food superintendent, who operated a system of canteens, where the menus were decided at the local level, and every New Yorker had to eat in these canteens. Well, the food will be awful, and that’s kind of what we’ve decided to do with schooling. That instead of harnessing the urban ability to provide innovation, competition, new entry, we’ve put together a system where we turned all that system off. And we’ve allowed a huge advantage for a local, public monopoly. It’s very, very difficult to fix this.

If the comments on his earlier blog post are any indication, many readers will push back against Glaeser’s ideas — especially those readers who don’t live in cities. Even though Glaeser’s arguments are generally empirical, this is the sort of topic — the triumph of cities, indeed! — that most of us think about as much with our emotions as with the more logical quadrants of our being. For that matter, it’s important to note that Glaeser himself grew up in Manhattan and has lived in Chicago and Boston, which might make one wonder whether his appreciation for urbanity might have an emotional component as well.

At the end of the podcast, I ask Glaeser to name his favorite city.

“I’m selling a book!” he said. “I can’t possibly pick favorites.”

But he did.