Dishonesty is all about the small acts we can take and then think, 'No, this not real cheating.' So if you think that the main mechanism is rationalization, then what you come up with, and that's what we find, is that we're basically trying to balance feeling good about ourselves.

Big Data is like teenage sex: everyone talks about it, nobody really knows how to do it, everyone thinks everyone else is doing it, so everyone claims they are doing it.

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.

If you have loans, the first thing you want to do is say, "Okay, look I have a credit card, if I really need to borrow, I have this emergency money that I can get, but for now there is no reason for me to keep cash at zero percent interest rate and at the same time, pay all of this money out. So, I think people need to figure out quickly how to pay loans and how much cash they should really keep.

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.

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.

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 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?

If you think of people as making decisions actively, every time we think about the cup of coffee, we say, "How much will I enjoy the cup of coffee, what else could I not do in the future because I buy this cup of coffee?