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。
A mathematician is a person who can find analogies between theorems; a better mathematician is one who can see analogies between theories and the best mathematician can notice analogies between analogies.
可持续性不是一种选择;它是我们行业未来的必需品。
当你想要放弃的那一刻,想想你为什么坚持了这么久。