《论衡·卷二十八·正说篇》
然而《周礼》的六典和现存的《礼经》却并不相符合，今天的《礼经》不一定就是周礼，那么也应该怀疑今天的《易》不一定就是《周易》了。
六典不与今礼相应，今礼未必为周，则亦疑今《易》未必为周也。
However, the "Six Rites" of "Rites of Zhou" and the "Classic of Rites" which exists do not match. The "Classic of Rites" today may not be the "Rites of Zhou", so we should also doubt whether the "Yijing" today is "Yijing" of Zhou Dynasty.