變得快樂的技巧幾乎完全不同于不悲傷的技巧。
The true discovery of America is before us. The true fulfillment of our spirit, of our people, of our mighty and immortal land, is yet to come.
No society can surely be flourishing and happy， of which the far greater part of the members are poor and miserable.
The goal of mathematics is to understand the universe in a deeper way.
We are going to die, and that makes us the lucky ones.