Interesting. I recently came to the same conclusion (for myself anyways) - my thinking became a lot bigger after reading (addmittedly pop-)economics books like Freakonomics, Hidden Order (the better of the two IMHO), etc. It's not perfect, but I have yet to see a better explanation than the utility-maximizing principle (I made up that name but you get the idea). The key is to remember that all utility is not created equal, and that there are diminishing returns. (sorry, rambling)