Of course, any hexagram can change into any other if the relevant lines are changing. However, there are other relationships between hexagrams that are particularly helpful in unfolding their meanings. Each hexagram stands at the centre of a constellation of others, and studying these subtle interconnections brings a deeper understanding. In a normal, full reading I would consider this constellation (amongst other connections) for both the primary and relating hexagrams.
The nuclear hexagram
This is created from the original hexagram’s inner lines. A hexagram’s lines are numbered, from the bottom upwards, 123456, and the nuclear hexagram is formed from lines 234345. To take an example: with the original hexagram 33:
6  |
| 5 |
| 4 |
| 3 |
2  |
| 1 |
… then the nuclear hexagram would be #44:
| 5 |
| 4 |
| 3 |
| 4 |
| 3 |
| 2 |
The nuclear hexagram is like a seed in the original hexagram: something held in potential, that might grow. It can be a hidden possibility, or a hidden issue that’s being worked out through the original hexagram.
More on nuclear hexagrams from the blog:
- Nuclear hexagrams: why bother?
- The heart of the Home: Not Yet Across
- The Family of Hexagram 37
- Nuclear families of 37 and 38
Complementary hexagram
The complement of a hexagram is its mirror image: each broken line is replaced with a solid one, and vice versa. So the opposite of Hexagram 33, Retreating –
… is Hexagram 19, Nearing.
You can imagine how these two together form a yin/yang pair… like the sides of a coin. By showing exactly what your situation isn’t like, this hexagram helps you to understand more closely what it is.
More from the blog on complementary hexagrams:
- Casting the Vessel (a remarkable pattern created by complementary patterns in the Sequence – fully ‘worked out’ in the Sequence article in Change Circle)
- Pushing Upward, step 4 (more hexagrams of context)
Contrasting Hexagrams
The Sequence of hexagrams in the I Ching is arranged in contrasting pairs. The pair is usually generated by turning the original hexagram upside down. So the contrast to Hexagram 33 is Hexagram 34, Great Strength:
Some hexagrams, though, are symmetrical – they are the same if turned upside down. In these cases, the complementary hexagram is also taken as the contrast. For example, the complementary and contrasting hexagram to 30, Clarity –
– is 29, Repeating Chasms:
The contrasting hexagrams are paired in the I Ching – in other words, this is a vital part of its basic structure. They provide a context that helps to define the primary hexagram, often as part of a larger unit of meaning.
This relationship is the subject of the Zagua, one of the Ten Wings of commentary that make the I Ching a classic, which is included in complete translations.
The hexagram of sequence
This is simply the hexagram that immediately precedes the one you cast in the I Ching. It reveals the roots of your situation, or perhaps something which you will have to acknowledge or work on before you can exploit the current situation’s full potential. Like the contrasting hexagram pairs, the sequence of hexagrams has a Wing to itself, theXugua. This hexagram can’t be generated from the original one (though it will be the same as the contrasting one 50% of the time, of course) – you have to look it up.
Here’s a blog post on understanding Hexagram 46 in the light of 45, and one on Using the Sequence in readings.