When you can't go back, you have to worry only about the best way of moving forward.

Contemplating the weaknesses of others is easy； contemplating the weaknesses in yourself is hard， but it pays a much higher reward.

一切事物都完备地存在于我心中。反观自身而达到真诚，快乐没有比这更大的了。

数学是一种让我们能够描述无法描述的事物的语言。