艺术家必须既是诗人又是工程师。
La vie est une longue leçon d'humilité.
I have a dream that one day this nation will rise up and live out the true meaning of its creed.
经济研究应旨在为现实世界的决策提供信息。
A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.