How did the saying that the winter solstice lasts for three days come from?

This is the ancient description of the winter solstice, and the source cannot be verified.

In ancient times, the winter solstice was divided into three phases: "the first phase of earthworm knot;" Two-phase angular solution; Waiting for the spring to gush out. "

1. Earthworm knot: It is said that earthworms are creatures with yin bending and yang stretching. At this time, although the yang has increased, the yin is still very strong, and the earthworms in the soil are still curled up.

2, Mi Jiao solution: it is cloudy from summer to the sun, so the deer feels yin and solves the angle; It's a sunny day in winter, so Amy feels sunny and harmonious. The ancients thought that the elk's horns were facing the afterlife, so they were cloudy. In winter, the sun began to recover, and the elk felt that the yin gradually retreated and solved the horn.

3. Water spring movement: The water spring buried deep in the ground began to flow because of the spirit of the sun. Because of the birth of yang, the spring water in the mountain began to flow and get warmer at this time.

The origin of three stages of extended data:

China's astrology culture has a long history and is profound. The ancients began to explore the mysteries of the universe very early, and thus deduced a complete and profound star-watching culture. The Big Dipper is an important astrological sign in the northern hemisphere (China is located in the northern hemisphere). The natural rhythm of the corresponding area in the northern hemisphere gradually changed during the rotation of the Big Dipper, so it became the basis for ancient people to judge the change of solar terms.

"Twenty-four solar terms" is the product of ancient farming civilization, and farming production is closely related to the rhythm of nature. It is a knowledge system formed by ancient ancestors following the farming season and observing the movement of celestial bodies to understand the changing laws of medieval (seasonal), climate and phenology. Each solar term represents different changes in time, climate and phenology.