I'm mentioning all this -- I'm mentioning all this because I think this is not merely a personal problem; you may think I'm wrong in this, but I think we live in an age when our lives are regularly punctuated by career crises, by moments when what we thought we knew -- about our lives, about our careers -- comes into contact with a threatening sort of reality.
I'm not a saint, I'm a sinner.
It's not about ideas. It's about making ideas happen.
一支最甜美的歌，往往是用于歌颂最悲伤思维的歌。
动力学的方程在用变分法的语言表达时是完全的。
Psychology is a science, and teaching is an art; and sciences never generate arts directly out of themselves.