Ah, at last we come to the end. This chapter is about the knowns, the known unknowns and the unknown unknowns. While that’s a somewhat hard to follow sentence, it does make for a nice contingency matrix, and is really the crux of the Black Swan argument. Here’s my take:

One of the most dangerous mistakes you can make is to confuse unfamiliar and improbable.  What you don’t know CAN hurt you.