数学家是能在定理间找到类比的人;更好的数学家能在理论间看到类比;而最优秀的数学家能注意到类比之间的类比。
We are all experiments in progress.
If we want clean air and water, we must start by protecting our forests.
城市冰冷而空旷,没人在周围评判我。