the explanation of the trigrams in the book of changes, expanding on the images of the eight trigrams

乾為天，為圜，為君，為父，為玉，為金；為寒，為冰；為大赤；為良馬，為老馬，為瘠馬，為駁馬；為木果。

The chapter in "Shuo Gua Zhuan" lists extensively the symbolic images associated with the Eight Trigrams. "Qian" represents Heaven, and also represents a circle, since "huan" means circle, and the heavenly body is round and continuously moves; it also represents a sovereign and a father; it represents jade and metal, as both are hard and clean in quality; since "Qian" is located in the northwest, which is the time of severe winter, it also represents cold and ice; its color resembles the sun, thus it is represented by the great red color, the color of the red flag used in court ceremonies; in terms of horses, it represents good horses, old horses, thin horses, and horses with mottled coats; in terms of plants and trees, it represents the fruits on trees. All these symbolic images reflect the virtue of "Qian," which is pure and strong, never ceasing: the horses are taken for their continuous movement, while the fruits on trees represent the beginning of life in a year, just as "Qian" is the source of all things.

坤為地，為母，為布；為釜；為吝嗇；為均；為子母牛；為大輿；為文；為眾，為柄；其於地也為黑。

"Kun" represents the earth, the mother, and silk and brocade (the term "bu" also refers to ancient currency, symbolizing its widespread distribution). It signifies a cooking pot, capable of containing things and bringing about transformation. It denotes frugality, referring to the earth's virtue of gathering and concealing. It signifies fairness, meaning it carries all things without partiality. It represents a cow with a calf, symbolizing its gentleness and ability to give birth. It signifies a large cart, representing its capacity to bear heavy loads over long distances. It signifies ornamentation, as all things are mixed on the earth to form patterns. It signifies the multitude; it signifies a handle, as all things take the earth as their foundation, just as objects have handles to hold. In terms of color, Kun is black, the color of pure yin.

震為雷，為龍，為玄黃；為旉；為大塗；為長子；為決躁；為蒼筤竹；為萑葦；其於馬也，為善鳴，為＄足，為作足，為的顙；其於稼也，為反生，其究為健，為蕃鮮。

"Zhen" represents thunder, dragon, and the mixture of heaven and earth (xuanhuang). Xuan is the color of heaven, and Huang is the color of earth. Zhen signifies the beginning of one yang force moving underground, where the colors of heaven and earth blend, hence xuanhuang; it also represents "fu," meaning flowers spreading out; the great way; the eldest son; decisiveness and impetuousness, indicating a quick and vigorous disposition; young green bamboo, and reed and bulrush, all symbolizing things that sprout and grow easily in spring. In relation to horses, it represents a horse that is good at neighing, a horse with a white mark on the left hind leg, a horse whose four legs move together when walking, and a horse with a white forehead. In relation to crops, it represents "fansi," meaning plants like hemp and beans that have a shell and break through the soil to grow upward. When vibration reaches its extreme, it transforms into strength, hence "its ultimate manifestation is strength," and thus grass and trees flourish and become vibrant.

巽為木；為風，為長女；為繩直，為工；為白；為長；為高；為進退；為不果；為臭；其於人也，為寡髮，為廣顙，為多白眼；為近利市三位；其究為躁卦。

"Xun" represents wood, wind, and the eldest daughter; it symbolizes a rope straightening, and the work of artisans, as woodworkers use a plumb line to make things straight, hence Xun signifies the image of a rope and craftsmen; it is associated with white, length, height, and movement forward and backward, as wind moves without constant direction, thus it has the image of indecisiveness and fragrance. In the human body, it represents someone with sparse hair, a broad forehead, and prominent white of the eyes. Xun is located in the southeast, close to "Li" which is associated with the noon market, hence it signifies proximity to market profits, yielding threefold interest. Xun's nature is to enter and conceal, and when movement reaches its extreme, it turns into restlessness, thus it is said "its ultimate form is the Zhen trigram," ultimately leading to Zhen.

坎為水，為溝瀆；為隱伏；為矯輮；為弓輪；其於人也，為加憂，為心病，為耳痛；為血卦，為赤；其於馬也，為美脊，為亟心，為下首，為薄蹄，為曳；其於輿也，為多眚；為通；為月；為盜；其於木也，為堅多心。

"Kan" represents water and ditches; it signifies concealment, as a single yang is hidden within two yin, thus symbolizing concealment. It also signifies "correcting and bending," where straightening a bend is called "correcting," and bending a straight line is called "bending." It represents bows and wheels, both of which are formed through correcting and bending. In the human body, it signifies heavy worry, heart disease, and ear pain. Since blood in the human body is like water in the earth, "Kan" is the blood hexagram, and its color is red. In horses, it signifies a horse with a beautiful back, a horse with a quick and restless temperament, a horse that lowers its head, a horse with worn-out hooves, and a horse that moves with difficulty. In vehicles, it signifies many troubles and difficulties. It also signifies smooth passage, the moon, and thieves. In plants and trees, it signifies trees with hard wood and many knots, such as thorn bushes and jujubes.

離為火，為日，為電；為中女；為甲冑，為戈兵；其於人也，為大腹；為乾卦；為鱉，為蟹，為蠃，為蚌，為龜；其於木也，為科上槁。

"Li" represents fire, the sun, and lightning. Since Li is located in the south and the south is associated with fire, and the sun is the essence of fiery energy, it is associated with the sun and lightning. It also represents the middle daughter, armor and helmets, and spears and weapons. The trigram Li is externally strong and internally gentle, just as armor and weapons are used to protect the inner softness. In the human body, it represents a large-bellied person, as the center is hollow and the exterior is covered. It is also a dry trigram, as fire has a drying quality, hence it is said to be associated with the乾 (Qian) trigram. Additionally, it represents turtles, crabs, snails, clams, and tortoises, which all have hard shells on the outside and soft bodies inside. In plants and trees, it represents trees with hollow centers and dry, withered tops.

艮為山，為徑路，為小石；為門闕；為果蓏；為閽寺；為指；為狗，為鼠，為黔喙之屬；其於木也，為堅多節。

"Gen" represents mountain, mountain paths, small stones; gate towers, that is, the pavilions on both sides of palace gates; "gǔ luǒ," which refers to fruits from woody plants called "gǔ" and fruits from herbaceous plants called "luǒ," such as gourds; "hūn sì," meaning the gatekeepers and palace attendants who are responsible for guarding the gates; fingers; dogs, mice, and fierce black-mouthed beasts; and in plants, it refers to trees that are hard and have many knots. All these images reflect the meaning of "Gen" as "stopping": mountains remain stationary and do not move, gatekeepers stop people from entering or leaving, dogs and mice with black mouths can guard and bite, and trees with many knots have the most firm stopping quality.

兌為澤；為少女；為巫；為口舌；為毀折，為附決；其於地也，為剛滷；為妾；為羊。

"Du" represents marshland; a young maiden; and a shaman. In ancient times, a woman who could communicate with spirits through dance and song was called a shaman, while a man was called a xie. The shaman used speech and words to connect with the divine, hence "Du" signifies a shaman; it also represents speech and words; and signifies destruction and breaking, as the top line of "Du" is broken, resembling the damage and breakage of objects. "Du" also signifies attachment and departure, encompassing both meanings of reliance and leaving. In terms of land, it represents hard saline land; it also signifies a concubine, as the position of a young maiden is lowly, hence it is associated with a concubine; and it represents a sheep. "Du" has one yin line appearing over two yang lines, symbolizing the meaning of harmony and joy expressed outwardly.