What kind of people would be able to rationalize better than other people? Better storytellers, right? Creative people, right? Because if you're creative, you find more ways to cheat and still yourself a story about why this is okay.

We are all far less rational in our decision-making than standard economic theory assumes. Our irrational behaviors are neither random nor senseless: they are systematic and predictable. We all make the same types of mistakes over and over, because of the basic wiring of our brains.

Money are very difficult to think about. So, we think about money as the opportunity cost of money. So, we at some point went to a Toyota dealership and we asked people, what will you not be able to do in the future if you bought this Toyota?

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.

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.

Once you break the social norm and create a new social norm, all of a sudden it can stay with us for a long time.

The real issue is, how much goodwill do you invest in the work? And goodwill is not something that we can buy with money. It's very hard to buy goodwill with money.