A mathematician's work is never done; there are always more problems to solve.
People change and forgot to tell each other.
数学之美不仅在于其抽象的优雅，还在于其建模和解决现实世界问题的深刻能力。
"The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' but 'That's funny...'"
It is on the strength of observation and reflection that one finds a way. So we must dig and delve unceasingly.
Success is nothing without someone you love to share it with.