In total, by giving people $30 bonus, Intel lost almost 5 percent of productivity. That's a lot. Now, think about it. You give money because you think this would increase motivation. It actually decreases motivation.

We need to believe that we're good people, and we'll do just about anything to maintain that perception.

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.

The bad news is that ignoring the performance of people is almost as bad as shredding their effort in front of their eyes. Ignoring gets you a whole way out there. The good news is that by simply looking at something that somebody has done, scanning it and saying "Uh huh," that seems to be quite sufficient to dramatically improve people's motivations.

What you should do is wait until the end of each month, and then say, "OK, how much money do I have? How much do I need? Let me send the rest to retirement."

We can think about how we reduce the pain in paying. So, for example, credit cards are wonderful mechanisms to reduce the pain of paying. If you go to a restaurant and you are paying cash, you would feel much worse than if you were paying with credit card. Why? You know the price, there's no surprise, but if you're paying cash, you feel a bit more guilt.

If you want to spend more money in restaurants, use credit cards more than cash. If you want to spend less, use cash more than credit cards. But in general, we can think about how to use the pain of paying and how much of it do we want. And I think we have like a range. Credit cards have very little pain of paying, debit cards have a little bit more because you feel like today, at least it is coming out of your checking account, and cash has much more.