孔穎達為《周易》作正義，統一經說，採用了王弼、韓康伯注，取得官方的地位。王弼以其玄學背景，黜象數而講義理，其《周易注》與孔穎達《周易正義》成為「道家《易》」代表。經宋明理學發展，王弼《周易注》並無法定於一尊，程頤有《易程傳》，朱熹有《周易本義》等「儒家《易》」作。時至今日，《周易》乃本著其變易的特質，諸家各憑所好解讀，同一字之義，常有相對不同的解釋，令讀者心生困惑。〈夬〉卦〈大象〉文中「居德則忌」一詞，朱熹就以「不詳」存疑，因此溯流求源，釐清各家之說，實有其價值。因此，本文擬就〈夬〉卦之卦象與卦義，尤其在分歧的「居德則忌」一詞，針對各家注解加以離析，以為或可分為五大詮解方式，分別是王弼、孔穎達「居德明禁」、程頤「居德約防」、王安石「功成弗居」、項安世「積德忌決」與來知德「居澤為忌」。其中程頤「居德約防」具有承上啟下的關鍵地位，他一方面繼承了王弼「居德明禁」之說，一方面提示了〈夬〉卦當有防潰決之義，當時與後世學者在防潰決的思考下，或以「功成弗居」消解之，或以「積德忌決」消解之。接著，筆者將各類注解，置於〈夬〉卦與〈大象〉的義理脈絡中。王安石「功成弗居」根據薄弱，項安世與來知德則失之片面。相對的，王弼之說以「則忌」為「明禁」實有其據，以卦體「上下之義」解釋〈夬〉卦卦義，實合理一貫，最能呼應易道「不易」之精神，程頤補以「有防禁則無潰散」之義，以解決「居德則忌」未有應之相的問題。最後，筆者將王弼〈夬〉卦〈大象〉之說與「修身」、「為政」二端相應，以為其言充滿現實治世的關懷，然而論者多以「道家《易〉」視之，實有重新審視的空間。

Con, Ying-da (a scholar of the Tang Dynasty) writed ”Zhengyi” for ”Zhouyi”, based on ”Zhouyi-zhu” which written by Wang Bi and Han, Kang-bo, make this book get official status. Wang Bi believes that moral principle is better than image-numerology. Besides, Wang Bi's ”Notes of Zhouyi” and Con, Ying-da's ”Zhouyi-Zhengyi” become the Representative of the Daoist Yi. But some of scholars believe that Wang Bi's ”Notes of Zhouyi” Can not be set at the only way. Cheng Yi's ”Yi Cheng zhuan” and Zhu Xi's ”Zhouyi Benyi” are the Representative of the Confucian Yi. From now on, scholars often have different views when they talk over ”Zhouyi”. For example, there is a saying 'Ju-De-Ze-Ji' in the book of ”JueGua-DaXiangChuan”, and Zhu Xi said that he did not understand. Therefore, I try to get at the root of the matter, and try to clarify the various. Thus, this question can be solved.