There are no chapters with twelve points and their names in Neijing, such as the word "eating time", which is not found in Neijing. The twelve-hour regimen is a summary of later generations and can only be used as a reference. In ancient times, twelve o'clock was called midnight, crow, pingdan, sunrise, food time, angle, day, day, sunset, and human destiny. This systematic view can be found in Hanshu.