The Heavenly Stems and Earthly Branches are a system of time recording created by ancient Chinese people, consisting of ten Heavenly Stems and twelve Earthly Branches. Among them, Ding is one of the ten Heavenly Stems, representing specific time periods and the Five Elements properties. This article will deeply analyze the time period corresponding to the Heavenly Stem "Ding" and its significance in the Five Elements and directions.

Constitution of the Heavenly Stems and Earthly Branches

The Heavenly Stems and Earthly Branches are the core of the ancient Chinese time recording system, consisting of ten Heavenly Stems and twelve Earthly Branches. The ten Heavenly Stems include Jia, Yi, Bing, Ding, Wu, Ji, Geng, Xin, Ren, and Gui, while the twelve Earthly Branches are Zi, Chou, Yin, Mao, Chen, Si, Wu, Wei, Shen, You, Xu, and Hai. The odd numbers of the Heavenly Stems and Earthly Branches are Yang, while the even numbers are Yin. They combine with each other to form the cycle of the Sixty Jiazi.

Yin and Yang Properties of the Heavenly Stems

In the ten Heavenly Stems, Jia, Bing, Wu, Geng, and Ren are Yang Stems, while Yi, Ding, Ji, Xin, and Gui are Yin Stems. As one of the Yin Stems, Ding corresponds to Bing Fire. Bing is the Yang Fire, representing the sun's fire, while Ding is the Yin Fire, symbolizing the fire of a lamp or candle. In the Five Elements, Fire is located in the South, so Ding Fire is also associated with the Southern direction.

Correspondence Between Earthly Branches and Time Periods

The correspondence between Earthly Branches and time periods is as follows: Zi hour (23:00-01:00), Chou hour (01:00-03:00), Yin hour (03:00-05:00), Mao hour (05:00-07:00), Chen hour (07:00-09:00), Si hour (09:00-11:00), Wu hour (11:00-13:00), Wei hour (13:00-15:00), Shen hour (15:00-17:00), You hour (17:00-19:00), Xu hour (19:00-21:00), and Hai hour (21:00-23:00). These time periods are closely related to people's daily lives, especially the four hours of Zi, Wu, Mao, and You, known as the "Four Major Hours."

Determination of the Ding Fire Hour

According to the rules of combination between Heavenly Stems and Earthly Branches, the hour corresponding to Ding Fire is Wu hour, i.e., 11:00-13:00. This is the noon time of the day when the sunlight is strongest, which coincides with the nature of Ding Fire. Therefore, when people refer to the hour with the Heavenly Stem "Ding," they actually mean Wu hour.

This article elaborates in detail on the constitution of the Heavenly Stems and Earthly Branches, their Yin and Yang properties, and their relationship with time periods and the Five Elements and directions. It specifically points out that the hour corresponding to the Heavenly Stem "Ding" is Wu hour, i.e., the noon time of the day. Understanding this knowledge helps us better understand the ancient Chinese concept of time and cosmology.