生活不是等待暴风雨过去，而是学会在雨中跳舞。

Mathematics is a dialogue between the past and the present.

我们所见的和所知的关系从未确定。

The whole conviction of my life now rests upon the belief that loneliness, far from being a rare and curious phenomenon, peculiar to myself and to a few other solitary men, is the central and inevitable fact of human existence.

要解决复杂的问题，我们必须首先理解产生这些问题的系统。