To summarize, using money to motivate people can be a double-edged sword. For tasks that require cognitive ability, low to moderate performance-based incentives can help. But when the incentive level is very high, it can command too much attention and thereby distract the person’s mind with thoughts about the reward. This can create stress and ultimately reduce the level of performance.

Interesting thing that is happening in American society is that people are starting to talk about money. I don't know how you feel about this, but for a long time, nobody was talking about money. It was a secret. And it's kind of very interesting because we do lots of stuff to portray to people about how much money we have, the clothes we wear and the cars we have and the house - they all kind of depict to other people, signal how much money we make, but we don't talk about it specifically.

Because cheating is easier when we can justify our behavior, people often cheat in small amounts: We can come up with an excuse for stealing Post-It notes, but it is much more difficult to come up with an excuse for taking $10,000 from petty cash.

The most difficult thing is to recognize that sometimes we too are blinded by our own incentives. Because we don’t see how our conflicts of interest work on us.

Imagine you owe on five credit cards, you owe five debts. So which debt should you pay first? And the answer is very simple: You should pay the one with the highest interest rate first. But that's not what people do.

Why would you take money out of your paycheck at the beginning of the month when you don't know how much money you'll need?

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.