这才是最厉害的:
Reports that say that something hasn't hanppened 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.
——By the minister of the DOD of the United States of America