Did Confucius write the I Ching?

No. The core of the I Ching — the 64 hexagrams with their Judgments and line statements, the Zhouyi — was in use before Confucius was born (traditionally 551 BCE). What tradition credited him with is the Ten Wings (十翼), the commentaries that turned a divination manual into a philosophical classic. Modern scholars mostly doubt that too, while agreeing that the Wings speak in a Confucian voice and that Confucius probably did study the book.

Here is the evidence, from the earliest sources to the present.

The traditional story

The classic account is in Sima Qian's Records of the Grand Historian (史記), written around 100 BCE, in his biography of Confucius:

孔子晚而喜易，序彖、繫、象、說卦、文言。讀易，韋編三絕。

"In his later years Confucius delighted in the Yi. He arranged the Tuan, the Xici, the Xiang, the Shuogua and the Wenyan. He read the Yi so much that the leather thongs binding its bamboo slips broke three times." That last image, 韋編三絕, became a Chinese idiom for diligent study.

Later the bibliography of the Han shu (漢書藝文志) summed up the authorship in a formula: 人更三聖，世歷三古 — "three sages in three ages of antiquity". Fu Xi drew the trigrams, King Wen of Zhou doubled them into hexagrams and wrote the Judgments (with the Duke of Zhou often credited for the line texts), and Confucius wrote the Wings. For about a thousand years this was simply what everyone knew. Commentators such as Kong Yingda and Cheng Yi read the Wings as the words of Confucius.

What the Analects actually says

The Analects (論語), the record of Confucius's sayings, mentions the Yi only rarely. The famous passage is in Book 7 (述而):

子曰：加我數年，五十以學易，可以無大過矣。

"Give me a few more years, so that at fifty I may study the Yi, and I may be free of great faults." This looks like direct evidence — but there is a textual problem. An early variant of the Analects, the Lu version, read 亦 ("also") where the received text has 易 (the Yi), which turns the sentence into something like "…so that at fifty I may study, and also be free of great faults." The two characters sounded alike. Scholars still disagree about which reading is original, and the Yi may not be in this passage at all.

The second passage, 13.22, is firmer. Confucius quotes the third line of Hexagram 32, Heng — 不恆其德，或承之羞, "if you are not constant in your virtue, disgrace may come upon you" — and then comments: 不占而已矣, "this is simply a matter of not needing to divine." The line is cited as moral wisdom, not as an oracle. That attitude, reading the Changes for its ethics rather than its predictions, is exactly what the Ten Wings develop.

The Mawangdui "Yao"

In 1973 archaeologists opened a tomb at Mawangdui, sealed in 168 BCE, and found a silk manuscript of the Zhouyi together with several previously unknown commentaries. One of them, called Yao (要, "Essentials"), describes Confucius and the Changes in detail.

It says that 夫子老而好易，居則在席，行則在囊 — "the Master in old age loved the Yi; at home it was on his mat, travelling it was in his bag." His disciple Zigong objects: had the Master not taught that those who rely on divination lack virtue? Confucius answers that he puts divination last and looks for the book's "virtue and meaning" (德義). He says he walks the same road as the court diviners but arrives somewhere different (同塗而殊歸), and he admits that later scholars might doubt him because of the Yi.

The Yao does not prove that Confucius wrote anything. But it shows that by the early Han, and probably earlier, people told stories of an elderly Confucius absorbed in the Changes and defending a moral reading of it. That supports Sima Qian's picture of the man, even if not his attribution of the texts.

The doubts

Questions began long before modern scholarship. In the Song dynasty Ouyang Xiu (歐陽修) argued, in his Questions of a Boy on the Yi (易童子問), that the Xici, Wenyan and other Wings contain contradictions and repetitions that one author would not produce, and so could not all be Confucius's work. Zhu Xi, writing soon after, kept the traditional attribution in general but insisted that the Zhouyi was first of all a book of divination, to be understood on its own terms before the Wings (Zhu Xi and the Zhouyi Benyi).

In the twentieth century the "Doubting Antiquity" movement went further, and most scholars now hold a view along these lines:

• The Zhouyi took shape in the Western Zhou, centuries before Confucius. The credit to King Wen and the Duke of Zhou is legend.
• The Ten Wings were written by several hands, from the Warring States period into the early Han. Passages introduced with 子曰 ("the Master said") record what later Confucians attributed to him, not dictation.
• Confucius himself probably knew the Changes and may have taught from it. The Analects shows him quoting a line for its moral sense, and later traditions, including the Yao, remember him as a reader of the book in old age.

There is no consensus on the exact dates of each Wing, and some scholars give Confucius's school a larger role than others. But hardly anyone today holds that he wrote the Wings in their present form.

Why it still matters

Even if Confucius did not write a word of it, the Confucian reading shaped the I Ching you meet today. The Great Image of every hexagram ends with "the superior person (君子), in accordance with this…" — moral advice drawn from the image. See who the superior person is. The Wenyan reads the opening words of Qian, 元亨利貞, as four virtues (Yuan Heng Li Zhen). Wang Bi, Cheng Yi and Wilhelm all follow this path of "meaning and principle" rather than pure omen-reading.

Reading a cast the Confucian way

You can borrow the attitude without settling the authorship:

• Read the line for conduct, not only for outcome. Ask, as Confucius did with Heng, "what does this say about how I should behave?" before "what will happen?"
• Use the Image. After the Judgment and any moving line, read the Great Image (大象) as advice for you.
• Keep the oracle in proportion. In the Yao, Confucius puts divination last. A cast is a prompt for reflection, not a verdict, and the Ten Wings read it that way.