Am Duong – Yin Yang are 2 principles, forces, components or 2 sides of Tao, symbolizing all opposites, conflicting but also complementary and inseparable.
Classification method
Currently, in “I Ching”, once Khôn is determined as Yin & Càn, Yang, 2 methods are applied to classify the Am Duong – Yin Yang of the trigrams.
- On the early heaven: Yin or Yang of the trigrams is determined based on whether it is birthed of Yin (Khôn ☷) or Yang (Càn ☰) as shown in the Fig. 1.
- On the late heaven: The Yin or Yang of the trigrams, except Càn & Khôn, is determined based on if it has only 1 Yin (broken) or 1 Yang (solid) line.
| Image | Name (Vietnamese) | On Early heaven (1) | On late heaven (2) | |
| 1 | ☰ | Can, Thien (Càn, Thiên) | D | D |
| 2 | ☱ | Doai, Trach (Đoài, Trạch) | D | A |
| 3 | ☲ | Ly, Hoa (Ly, Hỏa) | D | A |
| 4 | ☳ | Chan, Loi (Chấn, Lôi) | D | D |
| 5 | ☴ | Ton, Phong (Tốn, Phong) | A | A |
| 6 | ☵ | Kham, Thuy (Khảm, Thủy) | A | D |
| 7 | ☶ | Can, Son (Cấn, Sơn) | A | D |
| 8 | ☷ | Khon, Dia (Khôn, Địa) | A | A |
Am Duong (Yin Yang) is very important concept. Therefore, we need to find out What is the right Am Duong Classification method so that it can be applied throughout and consistently. Let’s start to understand the AD of Càn & Khon because they are the 2 most important trigrams.
Vietnamese language
Referring to the word Âm (Yin), Vietnamese people often think of something hidden, covered or the reverse side as in the sentences Âm phủ, Cõi Âm (world of the dead, underworld), Âm bản, Âm tính (negative), and Dương (yang), vice versa, related to Trần gian, Cõi dương (this world) and dương tính (positive).
In the 2 words Âm Phủ (underworld) and Trần gian (this world), we also see that Âm (yin) goes with Phủ (cover), that is, to cover up and Trần (Nake, without cover) goes with gian or Dương (yang).
The underworld, also known as the netherworld, is the supernatural world of the dead in various religious traditions and myths, located below the world of the living.[1]Chthonic is the technical adjective for things of the underworld1Source: Underworld – Wikipedia.
Similarly, in the 2 words Tâm (Heart, Spirit) and Tướng (the face) there are also hidden Âm (yin) and Dương (yang).
Ta (I, me) + Âm (Yin) = Tâm (Take the consonant T with the word Âm), which means the heart, spirit, all hidden inside each person.
And Ta (I, me) + Dương (yang) = Tướng (the face), is the expression, which appears outwardly.
Even in pronunciation, our mouth closes when we say the word Âm and opens when we say the word Dương.
The above evidences show that in Vietnamese, Âm means hidden, invisible, inside and Dương is visible, outside.
Càn & Khôn in current KD
The King Wen’s sutra for the 2 hexagrams or double trigrams of Càn & Khôn, states:
Càn: Big beginning, smooth, benefit, durable
Khôn: Big beginning, smooth, benefit, surrender ensures durability.
The only difference is in the last phrase. If Khôn (Earth) wants to be durable, it must follow Càn.
What is Càn that Khôn has to follow? Each trigram has many meanings, but the most important meaning of Càn is shown in the comments on each line of the 64 hexagrams given by Mr. Chu Cong Dan, the son of King Wen. Of the 7 lines of Càn, there are 5 with the word Long (Dragon).
Reading starts at line 1. Among all 64 hexagrams, only double Càn & double Khôn has an additional line No. 7.
7 — Headless Dragons. Good.
6 — The dragon rose too high, regretting it.
5 – The dragon appeared in the sky, beneficial to meet the gentleman.
4 — Jump over the abyss without error.
3 — Adults who are active all day, always careful, are not at fault.
2 – The dragon appeared on the surface of the field, beneficial to meet the gentleman.
1 – Hidden dragons don’t work.
Long, Rồng or Thìn means Dragon & is the symbol of the spirit, willpower, wisdom and what is very important that makes human different from other species is self-awareness. All are invisible, hidden & inside.
As for Khôn, it represents the material part, urges, needs, instincts, life experiences, knowledge … These are more visible, external or conspicuous, easier to grasp than what Càn represents.
So, from the beginning, hundreds of years before the Ten Wings, King Wen & his son had assigned Càn a symbol of the hidden, invisible & spiritual or Càn represents Âm (Yin) & Khôn, Dương (Yang).
However, the Ten Wings said the opposite “Càn represents things belonging to Yang, Khôn represents things belonging to Yin” 2Nguyễn Hiến Lê: Kinh Dịch Đạo Của Người Quân Tử, NXB Hồng Đức, and this concept of Càn-Yang and Khôn-Yin has been accepted and used for more than 2000 years.