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藝術超越國界；它說一種人人都能理解的通用語言。

If you're not stubborn, you'll give up on experiments too soon. And if you're not flexible, you'll pound your head against the wall and you won't see a different solution to a problem you're trying to solve.

To understand the future, one must first understand the past.

經(jīng)濟學家的角色既是科學家，又是工程師。