数学家研究纯数学不是因为它有用；他研究它是因为他喜欢它，他喜欢它是因为它美丽。
The mathematician does not study pure mathematics because it is useful; he studies it because he delights in it and he delights in it because it is beautiful.
The only way to make sense out of change is to plunge into it, move with it, and join the dance.
The value of an economic model lies in its ability to explain and predict.
Do you believe in the human heart? I don't mean simply the organ, obviously. I'm speaking in the poetic sense. The human heart. Do you think there is such a thing? Something that makes each of us special and individual?