Money is 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? Now, you would expect people to have an answer. But people were kind of shocked by the question. They never thought about it before. So, the most we got was people said, "Well, if I can't buy this Toyota, if I buy this Toyota, I can't buy a Honda." What is this thing? What is this value of price? Very hard to think about it.

That’s a lesson we can all learn: the more we have, the more we want. And the only cure is to break the cycle of relativity.

Kids don't care what party they have, right? They want cake and they want to run around. Nothing else matters. But in this escalation, all the kids want parties like their friends. So, if all the friends have an amazing, expensive party, they all want the same thing. If we all got to scale down as a coordinated effort, all the kids would have been just as happy.

Imagine you have six loans, small to huge. People want to close loans and because of that, they try to pay off the small loans, but that's not the right strategy. The right strategy, of course, is to pay the loan with the highest interest rate. People make this mistake and it costs them lots and lots of money, it's a very expensive mistake because interest rates accumulate and become very, very expensive very quickly.

With everything you do, in fact, you should train yourself to question your repeated behaviors.

We should teach the students, as well as executives, how to conduct experiments, how to examine data, and how to use these tools to make better decisions.

Money is all about opportunity cost. Every time you spend on something, that's something you can't spend on something else.