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.

You can think about life as a battle between you and a doughnut shop. The doughnut shop wants you to eat another doughnut and pay the money, and you want to do it in the short term, but in the long term it's not good for you either financially or from a health perspective.

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.

We're actually trying to develop an iPhone app, now that the Droid is out, we'll do it for that as well, if we ever learn how to program on this thing. But the idea is that to make money concrete. So, you can do this app, and it's not out there, but you can do the app. And you say, "I like vacation in the Bahamas, shoes, lattes, and books." And now, when you are tempted to buy something, that thing translates in terms of the things you are interested in.

With everything you do, in fact, you should train yourself to question your repeated behaviors.

The problem with opportunity cost is that opportunity cost is divided among many, many things.

Kids don't care what party they have, right? They want cake and they want to run around. Nothing else matters. But in this escalation, all the kids want parties like their friends. So, if all the friends have an amazing, expensive party, they all want the same thing. If we all got to scale down as a coordinated effort, all the kids would have been just as happy.