As countries appear and disappear, then I began to ask, what makes countries successful? And it turns out, after a long slog through geographies and ethnicities and all kinds of variables, it's the ability to adapt and adopt, what Darwin talked about.

It's not completely inconceivable that someday you'll be able to download your own memories.

The U.S. started with no stars. In fact, it started with a completely different flag. The last two were added in 1959, Hawaii and Alaska.

The housing crisis may not be the worst thing that's happened to New York City because it was becoming impossible for some of the young doctors, for some of the young artists, for some of the people that make the city so special to be able to live here.

Real estate prices are way out of whack with what people earn.

There are certain zip codes that generate a disproportionate share of patents, of startups, of wealth, of jobs. And it's really important if other parts of the country are going to want to create these tech centers.

When you brought the digital revolution in, all of a sudden, you could build a country like Singapore and take that country, which had the income per capita of Ghana in 1965, and make it something similar to the United States in one generation.