居安思危。思则有备，有备无患。
解释：处于安全环境时要考虑到可能出现的危险，考虑到危险就会有所准备，事先有了准备就可以避免祸患。
The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge.
"The only real failure in life is not to be true to the best one knows."
The true spirit of delight, the exaltation, the sense of being more than Man, which is the touchstone of the highest excellence, is to be found in mathematics as surely as in poetry.
"The unexamined life is not worth living."
文学是将痛苦转化为美的艺术。
The best way to predict the future is to invent it.
The historian is a prophet looking backwards.