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A classic is a book that has never finished saying what it has to say.

"Mathematics is not about numbers, equations, computations, or algorithms: it is about understanding."

The biggest risk is not taking any risk. In a world that's changing quickly, the only strategy that is guaranteed to fail is not taking risks.

可持續(xù)性不僅僅是植樹；它是為了正確的理由在正確的地方種植正確的樹木。