Filial piety is the concept that respect and deference should be given to elders within a family, and that there exists a defined hierarchy within a familial structure, mostly based on age and relation to other members.
This concept is easily transferred to political structures, and can be used to assert that one must know his place in society and show obedience, deference, and respect to those higher up in the societal hierarchy, with the emperor at the very top.