But because human being tend to focus on short-term benefits and our own immediate needs, such tragedies of the commons occur frequently .

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.

We don't really want a huge house, but we want the house to be slightly bigger than our neighbors, and a car that is bigger than our neighbor's, and they're going on vacation that's slightly more expensive, and this escalation happens that things got out of hand.

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.

If you ever go bar hopping, who do you want to take with you? You want a slightly uglier version of yourself. Similar ... but slightly uglier.

When people are in severe pain, there's an expression, you're a "pain person," and what that means is that nothing else matters.

We need to believe that we're good people, and we'll do just about anything to maintain that perception.