From 《
孝经·
孝治章》:
昔者明王之以孝治天下也 (In ancient times, enlightened kings governed all under heaven through filial piety). The Han dynasty adopted this Confucian doctrine as state ideology - posthumous emperor titles even prefixed
孝 (e.g.
孝文帝,
孝武帝). The saying
以孝治天下 became a defining slogan of Confucian monarchy.