《论衡·卷十八·感类篇》
上天表彰周公的功绩，强使成王用天子的礼节安葬周公，为什么不强使成王封周公以周王的称号，以符合安葬时用天子的礼节呢？ 
天彰周公之功，令成王以天子礼葬，何不令成王号周公以周王，副天子之礼乎？ 
The Young Masters and Young Lords were the king's relatives, so they had a high status and had the right to the title "Lord" and a fief. The title and the reality matched each other, just like the inside and outside of a thing.