《汉书·传·贾谊传》
夏商周三代的统治之所以长久，看过去的事就可知道了；然而不能依从的，是不效法圣贤的聪明。
夫三代之所以长久者，其已事可知也；然而不能从者，是不法圣智也。
The reason why the three dynasties of Xia, Shang and Zhou ruled for a long time can be known by looking at the past; however, what cannot be followed is not to follow the wisdom of the sages.