What makes cities work? How do humans live in such HUGE tribes. More than half of us live in cities.

I’m a new city transplant. I’m not sure I’ll ever get used to it, but it’s a fascinating topic to explore.

There’s no scientific metric for measuring a city’s personality. But step out on the sidewalk, and you can see and feel it. Two physicists explain one tidy mathematical formula that they believe holds the key to what drives a city. Yet math can’t explain most of the human-scale details that make urban life unique. So we head out in search of what the numbers miss, and meet a reluctant city dweller, a man who’s walked 700 feet below Manhattan, and a once-thriving community that’s slipping away.

Thanks Jad and Robert.

Cities – Radiolab.