Confucius remarked, "At fifteen I had made up my mind to give myself up to serious studies. At thirty I had formed my opinions and judgment. At forty I had no more doubts. At fifty I understood the truth in religion. At sixty I could understand whatever I heard without exertion. At seventy I could follow whatever my heart desired without transgressing the law."

中文：子曰：“吾十有五而志于学，三十而立，四十而不惑，五十而知天命，六十而耳顺，七十而从心所欲，不逾矩。”

注释：孔子说：“十五岁时，我已下决心投身于认真严肃的学习研究。三十岁时，我已形成了自己的观点和判断力。四十岁时，我已经不再有疑惑。五十岁时，我明白了宗教中的真理。六十岁时，我能够懂得任何我所听到的事情，而毫不费力。七十岁时，我能够遵从任何我心中所欲求的，而不超越律法。”