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The best performance improvement is the transition from the nonworking state to the working state.

The future belongs to those who can make leather without leaving scars—on the earth or its people.

U.S. energy independence doesn't mean isolation - we're still part of global markets.

數學的快樂來自于為理解而奮斗。

藝術的挑戰在于使不可見的東西變得可見。