1/6     What is the technical definition for a middle-class, lower-class, and
        upper-class? Is it based on income AND debt (mortgage)?
        \_ Probably closest thing I can think of is income quintiles:
           Poor, Lower MC, Middle Class, Upper MC, Rich
           \_ you forgot Uber-Rich (hedge funders, et al.)
        \_ http://en.wikipedia.org/wiki/Social_class
           But the definition of the classes probably depends on your agenda.
        \_ If I borrow lots of money and live lavishly, will I move up from
           a lower class to a middle class?
        \_ It is based on income and not net worth.