《资治通鉴·唐纪·唐纪八》
太宗向公卿大臣询问使国运长久的办法，萧说： 夏、商、周分封诸侯而统治时间长久，秦国不分封诸侯而迅速灭亡。 
上问公卿以享国久长之策，萧瑀言： 三代封建而久长，秦孤立而速亡。 
Emperor Taizong asked his public officials and ministers for advice on how to prolong the country's fortune, Xiao said: The Xia, Shang, and Zhou dynasties enfeoffed vassals and ruled for a long time, whereas the Qin Dynasty did not enfeoff vassals and perished quickly.