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

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.

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.

When you're in pain, tomorrow doesn't exist - just the pain - and the only thing that you want in the world is for it to go away.

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?

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.

Once you break the social norm and create a new social norm, all of a sudden it can stay with us for a long time.