When it comes to the mental world, when we design things like health care and retirement and stock markets, we somehow forget the idea that we are limited. I think that if we understood our cognitive limitations in the same way that we understand our physical limitations … we could design a better world.

Ownership is not limited to material things. It can also apply to points of view. Once we take ownership of an idea - whether it’s about politics or sports - what do we do? We love it perhaps more than we should. We prize it more than it is worth. And most frequently, we have trouble letting go of it because we can’t stand the idea of its loss. What are we left with then? An ideology - rigid and unyielding.

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.

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?

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 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.