The first step in liquidating a people is to erase its memory. Destroy its books, its culture, its history. Then have somebody write new books, manufacture a new culture, invent a new history. Before long the nation will begin to forget what it is and what it was.

"A mathematician is a device for turning coffee into theorems."

里氏替换原则是面向对象编程中的一个基本概念，它指出子类的对象应该能够替换超类的对象而不影响程序的正确性。

唯一能让你自由的是你自己的思想。