书籍是最安静、最恒久的朋友；它们是最易接近、最睿智的顾问，也是最耐心的老师。
The world is a great book, and we are the words.
The best stock to buy is the one you already own.
"The past is a foreign country; they do things differently there."
Inquiry into reality begins with the recognition of our ignorance.
发展经济学最终是为了改善人们的生活。