The end of history will be a very sad time. The struggle for recognition, the willingness to risk one's life for a purely abstract goal, the worldwide ideological struggle that called forth daring, courage, imagination, and idealism, will be replaced by economic calculation, the endless solving of technical problems, environmental concerns, and the satisfaction of sophisticated consumer demands.

To be a Negro in America is to be in a constant state of rage.

The most profound ideas in mathematics often come from asking the simplest questions.

Sustainability is not just about planting trees; it's about planting the right trees in the right places for the right reasons.

你比你想象的更有价值。