The Eight Trigrams (Bagua) are the eight basic single hexagrams of the I Ching. Each one is made of three lines, built from broken and unbroken strokes. The eight are Qian, Kun, Zhen, Xun, Kan, Li, Gen and Dui, standing for Heaven, Earth, Thunder, Wind, Water, Fire, Mountain and Lake in that order. Each trigram carries its own element and its own image from nature. Stack two trigrams on top of each other and you get a six-line hexagram, which is how the 64 hexagrams of the I Ching are built. Knowing the Bagua is the first step toward reading any hexagram.

For example, someone might cast a hexagram for the first time and see "Xun above, Kan below" without knowing what either name stands for. Once you recognize the eight trigrams, you can split any hexagram into an upper and a lower half and read each part, so it stops feeling like a wall of unfamiliar words.

What Are the Eight Trigrams? Definition and Basic Principle

In short: The Bagua are eight single trigrams of three lines each. They are the building blocks of all 64 hexagrams and 384 lines of the I Ching.

The smallest unit of the I Ching is the line. There are two kinds: an unbroken stroke is a Yang line, and a broken stroke is a Yin line. Stack 3 lines from the bottom up and you get one trigram. There are exactly 8 different ways to do it, and those eight are the Bagua.

If you are new to this, start with the idea of Yin and Yang lines, because they are the bricks that make up every trigram.

Each trigram in the Bagua is tied to an image from nature and to one of the Five Elements. This is how the I Ching uses familiar pictures of heaven and earth to describe states and the direction things tend to move in.

A full hexagram has 6 lines, made by joining two trigrams: the lower 3 lines are called the inner (lower) trigram, and the upper 3 lines are the outer (upper) trigram. Since there are 8 trigrams, the number of combinations is 8 times 8, which gives exactly 64 hexagrams. In other words, once you have the Bagua memorized, you are holding the key to the whole system.

The 8 Trigrams and Their Meanings: Image, Element and Nature

In short: Each trigram has its own image, element and nature. Qian and Dui belong to Metal, Zhen and Xun to Wood, Gen and Kun to Earth, Kan to Water, and Li to Fire.

The table below collects the eight trigrams in one place, and you can use it as a quick lookup when reading a hexagram. The directions follow the Later Heaven arrangement.

Trigram	Image	Element	Direction
Qian	Heaven	Metal	Northwest
Kun	Earth	Earth	Southwest
Zhen	Thunder	Wood	East
Xun	Wind	Wood	Southeast
Kan	Water	Water	North
Li	Fire	Fire	South
Gen	Mountain	Earth	Northeast
Dui	Lake	Metal	West

Here is one spot where many beginners slip, even when they look things up online: the element of each trigram. Remember these easily confused pairs.

• Qian is Metal, not Wood. Dui is also Metal, not Water.
• Zhen is Wood, not Fire. Xun is also Wood, not Earth.
• Gen is Earth, not Metal. Kun is also Earth, not Metal.

A short way to hold it in memory: Qian and Dui go with Metal, Zhen and Xun go with Wood, and Gen and Kun go with Earth. That leaves Kan as Water and Li as Fire, one element each.

As for their nature, you can build it from the image itself. Qian is Heaven, so it carries a strong, tireless drive. Kun is Earth, so it carries an accepting, nurturing quality. Zhen is Thunder, which suggests a jolt and a starting point. Xun is Wind, which suggests seeping in and going along with things. Kan is Water, which suggests depth and risk. Li is Fire, which suggests brightness and clinging to something. Gen is Mountain, which suggests stopping and standing firm. Dui is Lake, which suggests joy, harmony and openness.

Earlier Heaven and Later Heaven Bagua: What Is the Difference?

In short: The same eight trigrams can be arranged in two different layouts. The Earlier Heaven Bagua is traditionally linked to Fu Xi, and the Later Heaven Bagua to King Wen.

While studying the Bagua, you will run into two diagrams. This often confuses newcomers, who assume they are two different systems. In fact the eight trigrams are still Qian, Kun, Zhen, Xun, Kan, Li, Gen and Dui. Only the order and the position of each trigram change.

Type	Traditionally linked to
Earlier Heaven Bagua	Fu Xi
Later Heaven Bagua	King Wen

The Earlier Heaven arrangement is traditionally linked to the legendary Fu Xi. The Later Heaven arrangement is traditionally linked to King Wen, who is also credited in the I Ching tradition with the Judgment texts of the hexagrams.

If you are a beginner, you do not need to agonize over the two diagrams. What matters first is learning the 8 trigrams, with the right image and element for each. The two layouts are a more advanced layer, and you can pick them up gradually once the base is solid.

If you want to cast a hexagram and read the matching explanation, you can try it on HOROS.

Putting the Bagua to Work

In short: The Bagua are not just for memorizing. When you cast a hexagram, each half is a trigram, and their elements help you read the relationship in the situation you asked about.

Many beginners ask: once I have learned the Bagua, where do I use it? The answer is that every hexagram you cast is two trigrams joined together. You can only read the hexagram once you know the trigrams.

For example, in the Plum Blossom Numerology method, readers tell apart the trigram that holds the moving line from the trigram that does not, and then look at the Five Elements relationship between them. If you do not know the element of each trigram, this step stalls right away. That is why it helps to get the Bagua solid first.

The elements follow the familiar cycles of generating and restraining. In the generating cycle, Metal gives rise to Water, Water to Wood, Wood to Fire, Fire to Earth, and Earth to Metal. In the restraining cycle, Metal cuts Wood, Wood breaks Earth, Earth dams Water, Water puts out Fire, and Fire melts Metal. One thing few people notice: Metal and Wood restrain each other. They do not feed each other.

A gentle reminder: the I Ching speaks about tendencies and timing, not a fixed fate. No hexagram is entirely good or entirely bad. The same hexagram may flow well in one situation and call for care in another. Understanding the Bagua is meant to help you see your situation more clearly and act more on your own initiative, not to make you worry.

If you want to dig into how these eight trigrams grow from the very first steps, you can read about the Great Ultimate, the Two Modes and the Four Images, the middle stage between a line and a single trigram.

Final Thoughts: Five Points About the Bagua

Here are the main ideas worth keeping after this article.

• The Bagua are 8 single trigrams: Qian, Kun, Zhen, Xun, Kan, Li, Gen and Dui, each with 3 lines.
• Each trigram has an image from nature and an element. Remember the easily confused pairs, such as Qian and Dui both being Metal.
• Two trigrams joined together make a hexagram, and that is how the 64 hexagrams are built.
• Earlier Heaven is linked to Fu Xi and Later Heaven to King Wen. They differ only in layout.
• The Bagua speak about tendencies, not destiny, and help you look at a situation with more initiative.

Once the 8 trigrams are in your head, the best way to remember them is to practice. Try casting a hexagram on HOROS with a specific question you are unsure about, then look at the two trigrams that form your hexagram and at their elements. Learning and doing side by side makes the Bagua stick much faster than memorizing a table.