1973年，湖南長沙馬王堆三號西漢墓出土了一批帛書《周易》，包括了〈二三子問〉、〈繫辭傳〉、〈易之義〉、〈要〉、〈繆和〉、〈昭力〉等共六篇《易傳》。其中〈繫辭傳〉一篇文字基本上與通行本相去不遠，只是一部分通行本章節歸入了〈易之義〉、〈要〉篇中。但最令人驚訝的是，帛書〈繫辭傳〉並沒有通行本「大衍之數五十」的談筮法的一章，使人不禁懷疑原來的〈繫辭傳〉本來就是沒有這一章的。再者，我們比較一下《易經》和《易傳》的語言，本來就是兩套語言，兩個系統，前者是占筮性質，後者是義理性質。這兩套語言也見於通行本〈繫辭傳〉一篇中。但通行本〈繫辭傳〉上下篇共24章，除上篇第9章「大衍之數五十」是談筮法的之外，其餘23章都是談義理的，這便使兩者顯得有點格格不入。所以筆者很懷疑最早期談筮法的和談義理的本來是獨立的兩篇解《易》之作，這由六篇帛書《易傳》都是談義理的，而沒有談筮法的一段，亦足以證明。通行本的〈繫辭傳〉（又稱〈易大傳〉）是誤植了早期另外談筮法的解《易》之作的其中一章（段）為一篇，而成為現在這個樣子。而由今本〈繫辭傳〉中既有「〈乾〉〈坤〉成卦說」，又同時有「占筮成卦說」兩個不一致的成卦系統在一起的這點來看，它顯然地是一個綜合之作。本文因而推論先秦時代可能是有一篇專門講占筮的解《易》之作，和談義理的一篇〈繫辭傳〉並存。只不過由於孔子論《易》重視義理，不重視占筮，故儒門弟子沒有積極保存這篇專門談占筮的解《易》之作，因而後來失傳了，只留下「大衍之數五十」這一小段，保存在通行本〈繫辭傳〉中。

In 1973, the Silk Manuscript ”Zhou Yi” was unearthed from tomb no. 3 at Ma Wangdui which is a tomb of Western Han dynasty, in Chang Sha, Hunan. The manuscript includes documents such as Erh San Zi Wen, Xi Ci Zhuan (or Yi Da Zhuan), Yi Zhi Yi, Yao, Miao He, and Zhao Li. Among them, the Xi Ci Zhuan is basically the same as the existing version of the document. However, some parts of the unearthed Xi Ci Zhuan were incorporated in the Yi Zhi Yi and Yao documents. Most astonishing of all, the unearthed Xi Ci Zhuan does not have the Da Yan chapter which the existing version includes. Therefore, the author suspects that the original Xi Ci Zhuan didn't have this chapter. Moreover, if we compare the ”Yi Jing” and the ”Yi Zhuan”, they have different language systems and concepts; the former is about divination, the latter is about philosophical concepts. These two kinds of language system do exist in the existing version of Xi Ci Zhuan. The existing version has 24 chapters. Apart from the chapter 9 in part 1-the Da Yan chapter which is about divination, the remaining 23 chapters are all on philosophical concepts. This has made the two groups of chapter(s) very different from one another. Therefore, the author suspects that at the early time, there were two pieces of commentary on the ”Yi Jing”: one is on divination and the other one on philosophical concepts. This suspicion is supported by the fact that the six manuscripts unearthed from Ma Wangdui are all on philosophy. The author believes that the existing Xi Ci Zhuan is basically a piece of commentary on philosophy, but it has mistakenly incorporated the divination chapter from the divinatory piece of commentary. Furthermore, the existing Xi Ci Zhuan has two systems in the formation of ba-gua (eight diagrams), one formed by the qian and kun, another by divination. This has also proved that the existing Xi Ci Zhuan is a combination of two works together. Therefore, the author has inferred that in pre-Qin China, there were two pieces of commentary on ”Yi Jing”-the one on divination and the one on philosophy. Nevertheless, because Confucius emphasized philosophy but not divination in his study of ”the Book of Changes”, the piece of commentary about divination has eventually not been transmitted to the present time. Only the small chapter on Da Yan survives and is mistakenly incorporated into the piece of commentary on philosophy, that is, the Xi Ci Zhuan existing today.