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.

Not all debt is bad. From time to time we should get into debt when there's a good reason for that.

When parents have college savings accounts for their kids, their kids show higher social and cognitive performance.

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

Because cheating is easier when we can justify our behavior, people often cheat in small amounts: We can come up with an excuse for stealing Post-It notes, but it is much more difficult to come up with an excuse for taking $10,000 from petty cash.

Even the most analytical thinkers are predictably irrational; the really smart ones acknowledge and address their irrationalities.

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.