Regarding #4, no you are not. If housing prices tank, you are levered the wrong way, as millions of underwater homeowners have discovered. Owning your house o

Regarding #4, no you are not. If housing prices tank, you are levered the wrong way, as millions of underwater homeowners have discovered. Owning your house outright, somewhat paradoxically, makes it less awful if prices decline. I agree that "debt is bad" is simplistic, but good debt, in my mind, is self liquidating debt taken on for productive enterprise. Mortgages are not self liquidating, and consumer credit is of course much, much worse. Mortgages at least have the benefit of good rates and tax advantages, although the size of them can often make the practical cash-flow ramifications dicey. You are right, of course: at some rate of return, a sure thing at 3% becomes less attractive than an alternative investment. And you have to look at your broader investment basket to put together the appropriate mix of risk and returns. If paying off your mortgage involves say 20% of you net worth, that's different than 90% of it. So, as always, it depends. I do like the thought experiment where you ask yourself "If I had my house paid off, would I take out a mortgage to make this investment?"