Chengmen Sydney: In the Song Dynasty, there was a man named Shi Yang, who was a student of Cheng Zhu's Neo-Confucianism. In his forties, he went to Luoyang to visit Cheng Yi. When he and another classmate came to the Cheng family, it was snowing heavily and Cheng Yi was taking a nap. They stood outside the door and waited quietly until Cheng Yi woke up. At this time, the snow has fallen more than a foot deep. This is the story of "Chengmen Sydney" that has been passed down to this day.