"It doesn't mean we don't have problem. The fact is,we didn't need a rating agency to tell us that we need a balanced, long-term approach to deficit reduction.

VOA: special.2011.08.12

And just to give you some small defense of that approach, I always like to ask students, "Suppose we didn't have a single historical record, no newspaper, no diaries. You know nothing totally reliable for what happened in the latter part of the eighteenth century in America."

我可以给你们一个反驳的理由,我总是问学生们,"如果没有历史文献,报纸和日记,那么对于美国十八世纪后期的历史,你们将一无所知"

耶鲁公开课 - 古希腊历史简介课程节选

It's a secret number so that if Julius Caesar scrambled his message with the key 13, well, then the recipient had better know what that number is or realistically, -- and this is why it's kind of hard to buy -- into some of these age old algorithms, -- what would an alternative approach be to figuring out Julius Caesar's messages to his generals if he didn't know that secret number was 13?

它是一个机密的数字，以至于,如果凯撒大帝使用密钥13加密了它的消息，然后接收者最好知道那个数字是什么,实际上--这就是为什么很难,破解这些古老的算法-,有什么变换方法使凯撒大帝的将军,可以解密凯撒大帝的消息，如果他不知道,那个机密数字是13呢？

哈佛公开课 - 计算机科学课程节选