For example, in Zhou dynasty regulations governing clan ancestral worship, only the emperor could worship ancestors back to the fourth generation. Zhu Xi extended this rule to all families, and today, the altars that can be found in many rural homes can be traced back to Zhu Xi's ruling.
比如周代規定家族祭祀對象，只有天子可以祭祀四代祖先牌位，朱熹將此規定推及所有家庭，直到今天，鄉下人家正廳供奉的祖先牌位，仍以此為本。