科学是一项集体事业，每一代人都为之添砖加瓦。

The city's poor are like the roots of a tree: unseen, but essential to its survival.

全球竞争需要本地理解。

The stranger is close to us, insofar as we feel between him and ourselves common features of a national, social, occupational, or generally human, nature. He is far from us, insofar as these common features extend beyond him or us, and connect us only because they connect a great many people.

无知比知识更容易带来自信。