Mathematics is not just about numbers, equations, computations, or algorithms: it is about understanding.

Don't cry to quit, cry to keep going.

The world is full of obvious things which nobody by any chance ever observes.

人生就像骑单车，想保持平衡就得往前走。

【译文】 孔子说：“理想无法实现了，我准备乘筏漂到海上。会跟我走的，只有子路吧？”