What Do you Know?

Never have so many words been used to say so little, so many times.

"Reports that say that something hasn't happened are always interesting to me, because as we know, there are known knowns, there are things we know we know. We also know there are known unknowns; that is to say, we know there are some things we do not know. But there are also unknown unknowns -- the ones we don't know we don't know."

Donald Rumsfeld