What you should do is wait until the end of each month, and then say, "OK, how much money do I have? How much do I need? Let me send the rest to retirement."

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.

The people who need to overcome temptation to the highest degree have the hardest time doing it.

We usually think of ourselves as sitting the driver's seat, with ultimate control over the decisions we made and the direction our life takes; but, alas, this perception has more to do with our desires-with how we want to view ourselves, than with reality.

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

We're actually trying to develop an iPhone app, now that the Droid is out, we'll do it for that as well, if we ever learn how to program on this thing. But the idea is that to make money concrete. So, you can do this app, and it's not out there, but you can do the app. And you say, "I like vacation in the Bahamas, shoes, lattes, and books." And now, when you are tempted to buy something, that thing translates in terms of the things you are interested in.

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?