From The Maze Where Realities Converge - the psychedelic encyclopedia of reality from The Ultimate Comment

The I-Ching is a classical Chinese text showing how all things emanate from the most fundamental principles. Like the Qabalah, it is a system for simplifying existence by categorizing every phenomenon.

The universe had to start somewhere. It had to start at the beginning, right? So let our investigation start at the beginning of all things: Zero. This is Wuji.
But this is nothing. For there to be something, we must go further, to One. This is Taiji.
But One is necessarily static and unchanging, so for a dynamic universe, the must be at least Two. These are Yin and Yang.
The interplay of Yin and Yang creates the universe.

Qabalistically, Wuji, Taiji, Yin and Yang correspond to Ain, Keter, Binah and Chokmah.

In any situation, there are 2 Things That Can Happen: Yin and Yang.
Yin is represented in the I-Ching by a broken line: ¦
Yang is represented in the I-Ching by an unbroken line: |

If two events occur, one after the other, there are 2² = 4 Things That Can Happen:
Yin and Yin: ¦¦
Yang and Yang: ||
Yin and Yang: ¦|
Yang and Yin: |¦

Get the idea? Good. Now let's get into the meat of it

The eight trigrams

If there are three events, there are 2³ = 8 Things That Can Happen. These are the eight trigrams (in Chinese: the Bagua). Here they are:

||| Qian. The Hindu lingam. Pure phallic, creative, imposing, hard force. Heaven. Strength.
||¦ Xun. Air. Penetrating.
¦|¦ Kan. Dynamic. Dangerous.
|¦¦ Gen. Earth. Mountain. Completion. Standing still.
¦¦¦ Kun. Yoni. Pure feminine, yielding, soft force. Understanding.
¦¦| Zhen. Initiative.
|¦| Li. Radiant, but clinging and dependent.
¦|| Dui. Pleasure. Tranquil, devoted. The final Heh of the tetragrammaton

The 64 hexagrams

If there are six events, theis gives to 2⁶ = 64 Things That Can Happen. These are the 64 hexagrams of the I-Ching, the 64 possible combinations of | and ¦ in six lines. Each consists of two of the eight trigrams, an upper trigram and a lower trigram. (8² = 64.) The 64 hexagrams and their meanings may be studied at http://deoxy.org/iching

Links

• The I-Ching translated by Richard Wilhelm
• The I-Ching translated with commentary by Aleister Crowley
• A page on the I-Ching at Kheper
• Carl Jung's foreword to a translation of the I-Ching