The essence of mathematics is not to make simple things complicated, but to make complicated things simple.
君子不以水为镜,而以人为镜。以水为镜,只能看到面容;以人为镜,可以知道吉凶。
Thought is the most difficult task, which is why so few engage in it.
获得智慧是一种道德责任,它不仅仅是为了让你们的生活变得更加美好。有一个相关的道理非常重要,那就是你们必须坚持终身学习。如果不终身学习,你们将不会取得很高的成就。光靠已有的知识,你们在生活中走不了多远。