The I-Ching · Book of Changes
ZHOU YI 周易 · THE CLASSIC OF CHANGES
KEY TAKEAWAYS / TL;DR
- ◈The I Ching (c. 1000 BCE) is one of the oldest surviving divination and philosophical texts, and the foremost of Confucianism's Five Classics.
- ◈Its architecture is binary: Yin and Yang lines combine into 8 trigrams, which stack into 64 hexagrams — a complete matrix of human experience.
- ◈Leibniz noted in 1703 that the I Ching's hexagram system perfectly corresponds to binary arithmetic — the same system that underpins all modern computing.
The I Ching (易經), also known as the Book of Changes or Classic of Changes, is one of the oldest surviving texts in human civilization and one of the Five Classics of Confucianism. Its origins are shrouded in myth, with some traditions attributing it to the legendary sage Fu Xi (伏羲), believed to have lived nearly 5,000 years ago.
The core text, the Zhou Yi (周易) ("Changes of Zhou"), dates back to the Western Zhou dynasty (1000–750 BCE). By the 3rd century BCE, the "Ten Wings" (十翼) commentaries were added — transforming the Zhou Yi from a strictly divinatory manual into a profound philosophical and ethical text. In 136 BCE, Emperor Wu of Han officially designated it as the most important of the Five Classics.
Tradition credits King Wen of Zhou (周文王) with organizing the 64 hexagrams into their canonical order while imprisoned in the 12th century BCE, and composing the "judgments" (卦辞). His son, the Duke of Zhou (周公), is said to have written the line texts (爻辞).
BINARY ARCHITECTURE
The universe encoded in two elemental lines
The German mathematician Gottfried Wilhelm Leibniz noted the correspondence between the I Ching's hexagram system and his own binary arithmetic in 1703, remarking that Fu Xi had intuited the binary number system thousands of years before its formal invention.
THE EIGHT TRIGRAMS
Yin and Yang lines grouped into sets of three, representing the fundamental forces of nature
Creative, strong, initiating
Receptive, yielding, nurturing
Arousing, shocking, movement
Gentle, penetrating, gradual
Abysmal, dangerous, flowing
Clinging, luminous, clarity
Keeping still, meditative, stable
Joyous, open, communicative
64 HEXAGRAMS
When two trigrams stack, they form the complete matrix of human experience
Each hexagram is a figure of six stacked lines (爻 yao), read from bottom to top. The lower three lines form the Inner Trigram (representing the internal situation), while the upper three lines form the Outer Trigram (representing the external situation).
Since there are 8 possible trigrams, stacking any two yields 8 x 8 = 64 unique hexagrams. Each hexagram has a name, a Judgment (卦辞) attributed to King Wen, and six Line Texts (爻辞) traditionally attributed to the Duke of Zhou.
The King Wen Sequence (文王序卦) arranges the 64 hexagrams in a deliberate narrative order. Hexagrams are typically paired: the second in each pair is usually the first inverted.
DIVINATION
The art of consulting the Changes through yarrow stalks or coins
Yarrow Stalk Method
THE CLASSICAL APPROACH
The original and most revered method involves sorting 50 yarrow stalks through a ritualized process of division and counting. One stalk is set aside, and the remaining 49 are repeatedly divided into groups to determine each line.
This process is repeated six times (once per line), building the hexagram from bottom to top. The yarrow stalk method produces a subtly different probability distribution than coins, making "old" (changing) lines rarer and more significant.
Three-Coin Method
THE POPULAR APPROACH
Three coins are tossed simultaneously six times. Each toss produces a line: heads = 3, tails = 2. The sum determines the line type:
- 6 — Old Yin ⚋ (changing → becomes Yang)
- 7 — Young Yang ⚊ (static)
- 8 — Young Yin ⚋ (static)
- 9 — Old Yang ⚊ (changing → becomes Yin)
Changing Lines
THE SECRET KEY TO INTERPRETATION
The true depth of I Ching divination lies not just in the initial hexagram, but in the Changing Lines (变爻). When a line is "old" (6 or 9), it indicates a point of extreme energy that flips — old Yang (9) becomes Yin, old Yin (6) becomes Yang.
These changing lines create a second hexagram — the "relating" or "future" hexagram — charting your trajectory from one archetypal situation to the next.
A reading with no changing lines describes a stable situation; a reading with many changing lines suggests a period of profound transformation.
Global Influence
FROM CHINA TO THE WORLD
The I Ching gained widespread attention in the West through Richard Wilhelm's influential 1923 German translation, rendered into English by Cary F. Baynes in 1950. The Swiss psychologist Carl Gustav Jung wrote a famous foreword to the English edition, connecting the I Ching's logic to his theory of synchronicity.
The mathematician Gottfried Leibniz recognized the I Ching's binary structure in 1703, seeing in its hexagrams a natural precursor to the binary number system he was developing — the same system that would eventually underpin all modern computing.
Source: Wikipedia — I Ching, §History and textual origins & §Hexagrams & §Divination; King Wen Sequence; Stanford Encyclopedia of Philosophy, §Chinese Philosophy