最好的数学不仅正确，而且具有启发性。

One ought never to turn one's back on a threatened danger and try to run away from it. If you do that, you will double the danger. But if you meet it promptly and without flinching, you will reduce the danger by half.

The act of writing is an act of optimism. You would not take the trouble to do it if you felt it didn't matter.

The more I practice, the luckier I get.

The spread of liberal democracy and the integration of the world economy have created a situation in which the major powers are no longer willing to risk war with one another.

I'm so high, I can hear heaven.