Faith in a holy cause is to a considerable extent a substitute for the lost faith in ourselves.
对一项神圣事业的信仰相当程度上替代了已经失去的自信。
商场如战场,防人之心不可无。  
让自己振作起来的最好方法就是试着让别人振作起来。
The night is a liar, but the dawn tells the truth.
The study of computational complexity is not just about solving problems, but also about understanding the limits of what can be computed.