You can't change the past, but you can shape the future.

Keep your head up, God gives his hardest battles to his strongest soldiers.

If you can dream it, you can achieve it.

天下的老百姓如果都向上统一于天子,而不向上统一于天的意志,那么灾祸就还没有完全离去。

The most profound ideas in mathematics often come from asking the simplest questions.