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.

The companies that provide debt, what do you think their goal is? Is their goal for you to fully understand the cost of your debt? No. So they're basically creating these approaches to make you feel like it is incredibly cheap or just to think about the cost per day rather the cost per year or cost for a lifetime. So debt is very simple mistake.

The problem with opportunity cost is that opportunity cost is divided among many, many things.

People are irrational - and predictably so.

If you get people to feel that they are putting something, that they are creating it and so on, their love for the project would increase. The more something is yours, the more you're willing to invest in it.

I always found the appeal to the market gods a bit odd. Why would the market fix mistakes instead of aggravating them?

One of the big lessons from behavioral economics is that we make decisions as a function of the environment that we're in.