Tiangan (the pinyin of Mandarin Gan is gān) is ten orderly symbols, which can be recycled. It is followed by A, B, C, D, E, Ji, G, Xin, Ren and Gui. In ancient China, it was often used for naming, sequencing and dating.
Tiangan production
It started at the latest in the Xia Dynasty, and the obvious evidence is that there were emperors such as Kongjia and Yinjia in the late Xia Dynasty. But the official name of these ten symbols is Tiangan, which should be related to the earthly branches: the trunk is the main trunk and the branch is the branch, and the two relative names should appear together. Heavenly stems and earthly branches was used to record the sun in Shang Dynasty, and the use of earthly branches was later.
About the meaning of ten symbols, there is an easy-to-understand saying that ten symbols represent ten states and logical order of things:
Method of breaking the shell
B has just emerged from the ground and is still bent.
C and ice, booming.
Ding is like adolescence.
Wu Tongmao has reached the pinnacle.
I should have turned around and gone down the mountain.
G and B have the same root.
New Tong Xin, the seed of a new round.
Different fetal pregnancy
graphical user interface
Heavenly Stems and Earthly Branches
Simple heavenly stems and earthly branches will be repeated when the service period exceeds 10, and will start to repeat when the service period exceeds 12. Heavenly stems and earthly branches combination can reduce duplication and avoid confusion. In ancient China, a zipper-like combination of stems and soil branches was adopted, in which one chain tooth is a circulating heavenly stem and the other chain tooth is a circulating soil branch, and the least common multiple of the two can be 60 combinations.
Tiangan is a decimal, which is convenient for intuitive calculation; The earthly branch is decimal, which has advantages in recording time and month; The combination of trunk and branches is sexagesimal's, which is suitable for the situation that the interval (date) is very close without confusing (date). In ancient China, the combination of heavenly stems, earthly branches and stem branches was used flexibly to express the year, month, day and time, so the so-called birthday appeared.
Heavenly dryness and five elements, five elements of yin and yang
The ten images of heavenly dryness can be matched with the five images and five parties of the five elements according to their own meaning.
A and b are wood and the east.
C and d stand for fire in the south.
E, own soil, central.
Geng, Xin Weijin, Xi
Ren, Gui is water, North.
There are yin and yang in the sky;
A, c, e, g and n belong to yang.
B, D, Ego, Xin and Gui belong to Yin.
combine
There are five combinations of heavenly stems, which will become different five elements, so there will be different corresponding. In addition to the combination, the heavenly stems will collide with each other, so they will have different correspondences.
Tiangan combination: methyl-hexyl-earth-ethyl-heptyl-gold-propyl-octyl-water-butyl-nonyl-wood-pentyl-decyl combination fire.
Collision between heaven and earth: A Geng collided with B Xin, C Ren collided with D Gui.
Tiangan Heke: A, B, Mu, Ke, Wu, Ji, Tu, C, D, Huo, Ke, Geng, Xin, Jin, Ke, B, Mu, Ren, Gui, Shui, Ke, D, Huo.
The modern sky is dry
Used to indicate things without names, such as passers-by.
Used to indicate the quality level.
License plate of China people and national army (until 2004)
In chemistry, the Chinese names of some similar organic compounds are often distinguished by Tiangan.
Such as methane, ethane, ethylene, propane, methyl, ethanol, etc. , usually indicating the number of c (carbon atoms) in the molecule. For example, decane refers to an alkyl molecule with 10 carbon atoms.
The combination of stems and branches is still used in the lunar calendar.