《左传·定公·定公四年》
武王的同母兄弟八个人，周公做太宰，康叔做司寇，聃季做司空，其余五个叔父没有官职，难道是以年龄为主吗？
武王之母弟八人，周公为大宰，康叔为司寇，耼季为司空，五叔无官，岂尚年哉！
King Wu had eight brother born of the same mother. Duke of Zhou was chief minister, Kang Shu was minister of justice, Dan Ji was minister of construction, and the other five uncles had no official posts. Was it because seniority was emphasized?