数学不是沿着一条清理干净的高速公路小心翼翼地行进，而是一次进入陌生荒野的旅程，探险者常常会迷路。

"The truth is rarely pure and never simple."

我不相信上帝，但我想念他。

Don't write your name on sand, waves will wash it away. Don't write your name in sky, wind may blow it away. Write your name in the hearts of people, that's where it will stay.

Beliefs have the power to create and the power to destroy.