I Ching (Yijing): The Book of Changes, Explained

What the I Ching actually is

The I Ching (易經, Yijing), also called the Zhouyi or "Classic of Changes," is the oldest of China's five canonical classics and a foundation stone of Taoist thinking. At its heart it is a book of 64 hexagrams—six-line figures built from solid (yang) and broken (yin) lines—each paired with a judgment, an image, and layers of commentary. For more than three thousand years readers have used it both to seek guidance about a situation and to contemplate the nature of change itself. The Chinese Text Project's critical edition of the Yijing traces the core hexagram judgments to the Western Zhou period (c. 1000–750 BCE), as documented by the Chinese Text Project's Yijing edition source.

The 64 hexagrams

A hexagram is simply a stack of six lines, each either unbroken (━, yang) or broken (━ ━, yin), giving two to the sixth power, or 64, possible figures. Hexagram 1, Qian, is six yang lines—pure creative force; Hexagram 2, Kun, is six yin lines—receptive earth. The remaining sixty-two describe states of affairs: conflict, union, progress, retreat, nourishment, revolution, and so on. Each carries a short "judgment" (tuan) and an "image" (xiang) that invites reflection rather than prediction. The Stanford Encyclopedia of Philosophy notes that the text's enduring power lies less in fortune-telling than in its layered commentary on how situations mutate into their opposites, as recorded in the Stanford Encyclopedia of Philosophy entry on Daoism source.

How it was used—and still is

Originally the I Ching was consulted by heating a tortoise shell or counting yarrow stalks until the pattern produced a hexagram, which a diviner then interpreted for the court. Over centuries the practice shifted from state oracle to a personal instrument for clarifying one's own judgment. A common modern method uses three coins: six tosses build the hexagram from bottom to top, and any moving lines reveal a second, "future" hexagram showing where the situation is heading. The point was never to outsource decisions to fate but to slow the mind, frame the question honestly, and read the changing pattern beneath it—a method the Chinese Text Project's Daoism library situates within the wider classical corpus source.

The I Ching and Taoism

Taoist masters adopted the I Ching as a map of the dynamic balance between yin and yang and the perpetual motion of the Tao. Where the Tao Te Ching teaches wu wei—action without forcing—the I Ching shows that teaching in operation: every hexagram contains its own reversal, and the wise person moves with the turning of the situation rather than against it. Later Taoist alchemy, medicine, and Feng Shui all draw on the same eight three-line trigrams (qian, kun, zhen, xun, kan, li, gen, dui) that underlie the sixty-four. To see how the classic sits among Taoism's scriptures, read our FAQ on the main scriptures of Taoism, and for the philosophical root of this whole worldview, see what the Tao is.

How to approach it today

You do not need to believe in prophecy to benefit from the I Ching. Treat it as a mirror: pose a real question, cast a hexagram, and let the archaic language surprise you into a clearer view of your own situation. Begin with a single hexagram and its image rather than the entire commentary. For a companion reading of the Taoist fountainhead, our Tao Te Ching explained essay shows how the same insight into natural order appears in a different voice. The Book of Changes will not tell you what to do; it will show you the shape of the change you are already inside.