The history of all hitherto existing society is the history of class struggles.
至今一切社会的历史都是阶级斗争的历史。
The greatest enemy of a trader is hope.
To think is to confine yourself to a single thought that one day stands still like a star in the world's sky.
The best and most beautiful things in the world cannot be seen or even touched - they must be felt with the heart.
The process of solving a mathematical problem is often more important than the solution itself.