The earth can build a city wall, and the accumulation of virtue can make a solid ground. ——Li Bai

If you do a good deed, you will feel at ease; if you do a bad deed, you will feel ashamed. —— Shen Hanguang

The most valuable revolutionary quality is to remain unsullied in the mud and not corroded by the sugar-coated bullets of the bourgeoisie. ——Zhou Enlai

The saddest thing for a person is the death of conscience. —— Guo Moruo

Shyness is the emotion of fear or fear of humiliation, which can prevent people from committing certain despicable behaviors. —— Spinoza

One should be zealously committed to acting morally rather than talking about morality.

—— Democritus