圣人所以崇德而广业也！知崇礼卑，崇效天，卑法地。天地设位而易行乎其中矣！《易经：系辞上》

The Sage adores moralities, therefor he is able to expand his great undertakings. He is courteous as well as humble, acts in manners,. He worships and learns from Heaven, and he respectfully follows the laws on Earth. The Heaven and Earth both set regulations and rules for the theories in the 《Book of Changes》 to comply with.