In the U.S., I think there is an ideology of not telling kids what to do. Nobody to tell you who to marry, not tell you what job to pick. You're your own person. You have the freedom to choose, including the freedom to fail in magnificent ways. And I think that's the big difference. In other countries there is basically a social norm about saving that is passed from generation to generation. In the U.S. there isn't.

I think we could get people to both be more productive and happier. We're less productive as individuals. We're less productive as companies, and we're more miserable.

But suppose we are nothing more than the sum of our first, naive, random behaviors. What then?

Do you know how much money you would save if you changed your light bulb to compact florescent light bubs? How much would you save if you decreased your temperature of your house in the winter by one degree, or increase it by one degree? We just don't know these numbers, but I think displays could make it a memorable change in terms of attention, and also help us translate it in terms of concrete ways on what you can get.

One of the big lessons from behavioral economics is that we make decisions as a function of the environment that we're in.

People are irrational - and predictably so.

Money actually becomes even more difficult than other things because it's very hard to imagine what the benefits are to saving. So, imagine that you see a new bicycle, a new pair of shoes, or something today. You know exactly what you are giving up if you are not buying it, what are you gaining in the future if you are not getting it. So, you are giving up the bicycle today, what is it in the future? What will happen if you send another $1,000 to your retirement fund? What difference will it make? It is very, very hard to figure out.