If I gave you now, $10 as a gift, how happy would you be? Would you be happy, is the marginal $10, the best use of $10 you can use? Of course not. If I have you a CD, you know exactly what you are getting and you will have a value for it. So, money has lots of problems with it.

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.

individuals are honest only to the extent that suits them (including their desire to please others)

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.

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.

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.

But suppose we are nothing more than the sum of our first, naive, random behaviors. What then?