Some billionaires like cars, yachts and private jets. Others like newspapers.

Wall Street is littered with clever plans to use financial instruments to change behavior - carbon trading, for example. Some have changed the world, and others failed miserably.

There's a good argument to be made that companies that are private, where they're run by partnerships, where everybody has true stake in them and they're not playing with other people's money, that by default it's a safer system, because you really have skin in the game. You really own the company.

I have always looked at the world through the prism of money to some degree. If you could follow the money, it explains a lot of things, in all sorts of aspects of the world. You can look at politics through the prism of money. You can look at art through the prism of money. You can look at sports through the prism of money.

In many ways, education is a lousy business. Teachers are not normal economic actors; almost all of them work for less money than they might fetch in some other industry, given their skills and advanced degrees.

Unfortunately, I think it's very difficult to separate policy from politics. In a perfect world, in some instances, you probably would want to. In other instances, you'd probably say that the political element is important because it should, in a perfect world, match what the stakeholders need or want, or what the public is after.