誰翻譯一下倫斯菲的名言

．．．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.

這時倫部長回答記者問時講的一段話。獲得當年不知所云獎。