In ancient times the sage who invented Yi studied the rituals of worshipping gods through silent observation and then produced the yarrow. He tripled heaven and doubled earth (3 x heaven means that heaven 1 plus heaven 3 and heaven 5 equals 9 (pieces of yarrows), which is the number of the old masculine. 2 x earth means that earth 2 plus earth 4 equals 6, the number of the old feminine. Additionally 9 - heaven 1 = 8 is the number of the young feminine, and 6 + heaven 1 = 7 is the number of the young masculine) and then counted on these numbers (creating the method of divination with yarrows). He observed changes between Yin and Yang (i.e. brightness and darkness, the forms of the feminine Yin and masculine Yang in the heavens) and then established the hexagram (which consists of six different space-time continuum). He brought rigidity and tenderness (i.e. the forms of the masculine Yang and feminine Yin on the earth) into full play and then gave birth to the (masculine and feminine) line (which represents strength or yielding, good or bad, etc). He submitted to the virtue and norm (i.e. righteousness and moderation which are available for the lines at their appropriate positions) and then had the doctrine (of Yi) exist in appropriateness (of their actions). He searched the cause (of social conventions) and looked into the instinct (of Nature) and then attained the fate (i.e. the course of life).
In ancient times the sage who invented Yi followed the principle of life (i.e. the rule of Nature) constituting it. Herewith those which build the Dao (norm) of heaven are the feminine Yin (presented in the form of darkness) and masculine Yang (in the form of brightness). Those which build the Dao (norm) of earth are tenderness (the feminine Yin in the form of weakness or smallness) and rigidity (the masculine Yang in the form of strength or largeness). Those which build the Dao (norm) of humans are benevolence (the kindheartedness of the tender feminine) and appropriateness (the righteous action of the strong masculine).
By outfitting three domains (i.e. the domains of heaven, earth and humanity) with two lines each, Yi obtains the aid of six lines forming the hexagram (like the world where we live). By classifying (the whole of creation) into masculinity and femininity, (and) shifting between rigidity and tenderness, Yi exists at six positions and establishes its contents (i.e. the texts).
Heaven (Qian) and earth (Kun) are positioned (i.e. Qian is placed at the top and Kun is at the bottom); Dui, Li and Zhen are located counter-clockwise from Qian, while Xun, Kan and Gen are located clockwise to Kun. Hereafter each two trigrams at the diagonal positions have the opposite structures of the masculine and feminine, but coexist in the following ways: the mountain (Gen) and marsh (Dui) exchange breath (as the water of the marsh (Dui) evaporates becoming rain; it falls on the mountain (Gen) and then flows back to the marsh); the thunder (Zhen) and wind (Xun) approach each other (so that they can travel far together and with prestige); water (Kan) and fire (Li) (tend to subdue each other; however they remain parallel and) don¡¦t defy each other. The abovementioned mainly refers to Fu Xi Bagua (also called: earlier or pre-heaven Bagua) describing their origination and relationship. Eight trigrams mingle with one another, whereby 64 hexagrams are formed.
Numbers which are counted in a way of 1, 2, 3, 4, 5 ..... go along their course, while predicting future goes against (the stream of time: the past is behind us, while the future is in front and moves toward us); hence Yi is against the course of the numbers (i.e. ..... 5, 4, 3, 2, 1. Yi performs as if it stands in the future and watches backward what is happening along the course).
The thunder (Zhen) arouses the whole of creation and urges them to move. The wind (Xun) distributes (or disperses) them. The rain moistens them. The sun (Li) brightens (or warms and dries) them. Gen (the mountain) stops (i.e. restrains) them. Dui (the marsh) makes them be joyful. Qian (heaven) rules them like the king. Kun (earth) preserves (i.e. accommodates) them. The essence and function of each trigram is hereafter specified.
The following mainly refers to King Wen¡¦s Bagua (also called: later or post-heaven Bagua), and describes the applications of the eight trigrams.
The dominator of all creatures comes of Zhen (to move, the thunder). All creatures grow in unison at Xun (to enter, the wind). They become visible to one another at Li (clinging, fire). They are all served at Kun (submissiveness, earth). They feel joyful at Dui (joy, the marsh). They battle at Qian (perseverance, heaven). At Kan (the abyss, water) they toil and fatigue. All are accomplished at Gen (keeping still, the mountain).
All creatures originate from Zhen (to move, the thunder), like the plant being aroused by the spring thunder starting to sprout; Zhen denotes the east. They grow in unison (»ôqi2) at Xun (to enter, the wind), and Xun locates southeast; Qi2 (»ô) means unanimity of all life. Li (clinging, fire) provides brightness and makes all creatures be visible and able to see one another; it is a trigram of the south; the sage faces south to listen to the word and rule it with brightness; this phrase is derived from here. Kun (submissiveness, earth) is earth, where all creatures get nurtured; therefore it is said: all being served at Kun. Dui (joy, the marsh) is the autumnal equinox, where all creatures feel joyful while celebrating the fruitful harvest; therefore Dui is signified as joy. Battling at Qian (perseverance, heaven); Qian is a trigram of the northwest, and battle means the masculine and feminine approaching each other. Kan (the abyss, water) is water, a trigram of the north, and a trigram of toil and fatigue, as well as a place where all creatures return; therefore it is said: toil and fatigue at Kan. Gen (keeping still, the mountain) is a trigram of the northeast, wherein all have accomplished their tasks and are going to have a new beginning; therefore Gen is seen as accomplishment.
Those which perform as gods are those which manipulate the whole of creation. Nothing is more powerful than the thunder to move (i.e. to arouse and inspire) the whole of creation. Nothing is more efficient than the wind to bend (i.e. to widely reach and affect) the whole of creation. Nothing is dryer than fire to dry the whole of creation. Nothing is more joyous than the marsh to please the whole of creation (i.e. make them become prosperous and vivid). Nothing is moister than water to moisten the whole of creation. Nothing is grander than Gen to end and start up the whole of creation (like the mountain stopping everything, and like the new cycle of the King's Wen Bagua starting right after it). Therefore, water and fire at the diagonal positions of the King's Wen Bagua can reach to each other (as water flows downward and flames blaze upwards, whereby they generate steam and power). The thunder and wind stay next to each other in the King's Wen Bagua but won¡¦t revolt against each other (as they can reach far with prestige by travelling side-by-side; all life is aroused). The mountain and marsh exchange breath with each other (in this way Qi starts circulating) though they are separated by Kan and Qian. Then they vary with each other creating all phenomena of life.
Qian possesses the characteristic of perseverance, and Kun possesses the characteristic of submissiveness; Zhen, movement; Xun, entrance; Kan, the abyss; Li, clinging; Gen, keeping still (or stop), and Dui, joy (or to speak, or to persuade).
Qian denotes the horse, and Kun denotes cattle; Zhen, the dragon; Xun, the chicken; Kan, the pig; Li, the pheasant; Gen, the dog, and Dui, the goat.
Qian denotes the head, and Kun denotes the belly; Zhen, the foot; Xun, the thigh; Kan, the ears; Li, the eyes; Gen, the hand, and Dui, the mouth.
Qian denotes heaven; thus it is called the father. Kun denotes earth; thus it is called the mother. Zhen is one masculine line of Qian (the father) entering Kun (the mother) and occupying its bottom position as the first mating to become a masculine trigram*; thus it is called the eldest son. Xun is one feminine line of Kun entering Qian and occupying its bottom position as the first mating to become a feminine trigram*; thus it is called the eldest daughter. Kan is one masculine line of Qian entering Kun and occupying its middle position as the second mating to become a masculine trigram; thus it is called the second son. Li is one feminine line of Kun entering Qian and occupying its middle position as the second mating to become a feminine trigram; thus it is called the second daughter. Gen is one masculine line of Qian entering Kun and occupying its top position as the third mating to become a masculine trigram; thus it is called the youngest son. Dui is one feminine line of Kun entering Qian and occupying its top position as the third mating to become a feminine trigram; thus it is called the youngest daughter.
*According to Xi Ci Zhuan, Volume 2, Chapter 4: The masculine trigram is (constituted by the line stroke of) the odd number, while the feminine trigram is the even number. Therefore, Qian, Zhen, Kan and Gen are the male trigram, while Kun, Xun, Li and Dui are the female trigram.
Qian denotes heaven, roundness, the king, the father, jade, metal (or gold), cold, ice, bright red color, a good horse, an old horse, a thin horse, a belligerent horse, and the fruits on a tree.
Kun denotes earth, the mother, cloth, a cooking vessel, a calf and a cow, a big cart, a quality of culture, a multitude (of people), and the handler. It is symbolic of skimpiness and even distribution. Referring to earth, it is black.
Zhen denotes the thunder, the dragon, the blended color of dark blue and yellow, an avenue, the eldest son, the green young bamboo, and the spreading reed. It is also signified as: to apply (substance such as paint) all over, and changing decision swiftly and testily. Referring to the horse, it denotes the white rear left leg, and the white forehead; it is associated with a horse good at neighing, and a horse lifting its front legs. Referring to the crop, it means reverse growth. When Zhen behaves differently from its normal becoming perseverant, it symbolises lushness and vividness (of a plant).
Xun denotes wood, the wind, the eldest daughter, the marking cord, and white. It is also signified as: craftsmanship, a long distance, height, advancing and receding, indecision, and odor. Referring to humans, it denotes the sparse hair, a broad forehead, and the white of the eye very visible; it also means to earn a profit three times the average. When Xun behaves differently from its normal, it is a trigram of uneasiness.
Kan denotes water, the ditch, the bow, the wheel, the moon, the bandit, and red. It is also signified as: hiding in a prostrate way, and straightening and bending (something). Referring to humans, it means to worry about, the illness of the heart, and the earache; it is a trigram of blood. Referring to the horse, it denotes the beautiful spine, an impatient heart, a sagging head, the thin hoof, and a horse dragging (its hoofs). Referring to the carriage, it is associated with lots of man-made calamities, and to progress without obstruction. Referring to the tree, it denotes rigidity with lots of thorns.
Li denotes fire, the sun, lightning, the middle daughter, the armour, and weaponry. Referring to humans, it denotes the big belly. It is a hexagram of dryness. It also denotes the tortoise, the crab, the spiral shell, and the clam. Referring to the tree, it denotes a tree hollow and withered above.
Gen denotes the mountain, a footpath, small stones, the door (and / or watchtower), fruit or melon, the door guard, the finger, the dog, the mouse, and the various kinds of black-billed birds. Referring to the tree, it denotes a rigid tree with many nodes.
Dui denotes the marsh, the youngest daughter, the mouth and tongue, as well as the witch. It is signified as: to bend and break, and to adhere and to separate. Referring to earth, it denotes the hard and alkaline land. It also denotes the concubine, and the goat.