At 15 I set my heart on learning; At 30 I firmly took my stand; At 40 I had no delusions; At 50 I knew the Mandate of Heaven; At 60 my ear was attuned; At 70 I followed my heart's desire without overstepping the boundaries of right.
Some are born with knowledge, some derive it from study, and some acquire it only after a painful realization of their ignorance. But the knowledge being possessed, it comes to the same thing. Some study with a natural ease, some from a desire for advantages, and some by strenuous effort. But the achievement being made, it comes to the same thing.
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.
In ancient times, those who wished to illuminate the world with virtue first brought order to their nations. Wishing to order well their nations, they first harmonized their families. Wishing to harmonize their families, they first cultivated themselves. Wishing to cultivate themselves, they first rectified their minds. Those who wished to rectify their minds first made their intentions sincere.