To know, is to know that you know nothing. That is the meaning of true knowledge. When you say something, say what you know. When you don't know something, say you don't know. That is knowledge.

A man who reviews the old so as to find out the new is qualified to teach others.

Acquire new knowledge whilst thinking over the old, and you may become a teacher of others.

I do not want a friend who smiles when I smile, who weeps when I weep; for my shadow in the pool can do better than that.

The path may not be left for an instant. If it could be left, it would not be the path.

To be fond of learning is to draw close to wisdom. To practice with vigor is to draw close to benevolence. To know the sense of shame is to draw close to courage. He who knows these three things knows how to cultivate his own character. Knowing how to cultivate his own character, he knows how to govern other men. Knowing how to govern other men, he knows how to govern the world, its states, and its families.

He who fails to prepare, prepares to fail