If one were to regard father, older brother andruler like oneself, how could one not be filial
I interpret this as saying that filial actions, though important, are not as important as all around respect. Rather than emphasizing and teaching children to be filial one should teach them to treat everyone with the respect that they would give a family member. If you teach respect people will automatically be filial. I.E if you abuse your inferiors they will revolt and cause disorder. Like how the orphans in Annie revolted because Miss Hannigan did not show them any kindness or respect.