本文把《易．文言》「修辭立其誠」當作一句儒家「下學上達」的話，通過對《中庸》誠的觀念的重新解釋，對這句話進行了解讀。《中庸》的誠有三個層面，分別是宗教或神靈的誠、天道的誠、和心性的誠。前二者同屬超人文領域，後者則落在躬行實踐的道德層面。其中最值得注意的是天道層面的誠的概念。一方面它指的是一種超人文所以也是非道德的境界，另一方面，這境界因為也是修為所要達到的目標，所以誠這概念也被賦予最高的道德意義。本文認為〈文言〉這句話概括了這個修為階梯同時也凸出語言所處的關鍵地位。中國古代哲人重視語言規範，他們認識到語言的虛妄性格，因此嚴肅的對待語言，要求通過對語言行為的檢束達到淨化意識的效果，因此而回復到自然的認知狀態，只有真實，更無虛妄。宋儒解經，以後世的義理架構強加古人，過分強調誠的心性層面，又不謹守語文學規範，遂於「進德」「居業」文義之間，進退失據，無法自圓其說。

A close reading of the Confucian Classic Zhong Yong or On the Doctrine of the Mean reveals that its central concept cheng (ch'eng), which has commonly been translated as sincerity but would certainly fare better otherwise, perhaps with a freshly coined noun "realness," has ramifications pertaining to three different spheres of reality: the religious or numinous, the sphere of the Way of Heaven, and that of human moral practice. I would argue in this paper that it is this second sense of the word, rather than the third one, that could provide a most satisfactory reading for the famous passage about the relationship between language and reality xiuci li qi cheng of Wenyan, one of the Documents in the Book of Change. With this and other examples I show how Neo-Confucian scholars of the Song Dynasty tended to misread even the basic Confucian Classics as they, because, making no effort to set high standards in philological discipline for themselves, always inadvertently interpreted the Classics in terms of later metaphysis.