What do the Book of Changes and the Solstice of Half a Winter mean?

Half a winter solstice, the heavenly heart has not changed. At the beginning of the sun, when everything is not born, its meaning is as follows:

The winter solstice in a year is like noon during the day, which is twelve o'clock at night. Everything is calm, but it is ready to go.

Because of the revolution of the earth, the angle of the sun shining on the ground has changed, which has led to the changes of the four seasons-spring, summer, autumn and winter. Winter is related to the meaning of the end. When the sun is getting farther and farther away from us and the vitality disappears in the ice and snow, it is called winter.

So the sun is closest to us in summer and farthest from us in winter. It can also be said that in summer, the yang is the most abundant and the yin is the weakest; In winter, yang is the weakest and yin is the most abundant.

There are few characters mentioned in the Book of Changes, but Yan Yuan, the son of Yan, is mentioned here. "He is almost average" can probably represent this hexagram, so the first hexagram is represented by Yan Hui, Yan Hui is the solstice in winter, and the solstice in winter is the hope of mankind.