A mind needs books like a sword needs a whetstone.
心灵需要书本，就像一把剑需要磨刀石。
The truth is rarely pure and never simple.
书是一次跨越时间的对话。
The secret of being miserable is to have leisure to bother about whether you are happy or not.
It is always good to have a problem that you cannot solve. It means you have something to work on.
Poor is the man whose pleasures depend on the permission of another.
最大的性能改进是当系统从不能工作到能工作的时候。