论语

學而時習之，不亦說乎？有朋自遠方來，不亦樂乎？人不知而不慍，不亦君子乎？

Is it not delightful to acquire knowledge and practice it repeatedly? Is it not a pleasure to have friends visit from afar? Is it not noble to remain unworried when others fail to appreciate you?

吾日三省吾身：為人謀而不忠乎？與朋友交而不信乎？傳不習乎？

I reflect on myself three times daily: Have I been faithful in my duties? Have I been trustworthy with my friends? Have I practiced what I teach?

吾十有五而志於學，三十而立，四十而不惑，五十而知天命，六十而耳順，七十而從心所欲，不逾矩。

At fifteen, I set my mind upon learning. At thirty, I stood firm. At forty, I had no more doubts. At fifty, I knew the will of heaven. At sixty, I listened with ease. At seventy, I follow my heart's desires without overstepping the principles.

溫故而知新，可以為師矣。

Reviewing the old while discovering the new — this is the essence of a true teacher.

學而不思則罔，思而不學則殆。

Learning without thinking leads to confusion. Thinking without learning leads to danger.