漢末象數易學具有邏輯化和系統化的特征(以鄭玄的爻辰說、荀爽的乾升坤降說和虞翻的卦變說為典型)。首先,其推演包括兩重邏輯:一重是從乾坤二卦到十二消息卦、再到六十四卦,另一重是乾坤二卦在一卦內部的推演。其次,卦爻象的邏輯推演又是卦氣說的根本,后者只是前者落實到時空圖式上的結果,這就形成了漢末易學以邏輯為綱,以方法(易例)為目的特點,與西漢易學的"經驗性"性格迥然不同。漢末易學的天道觀以"天地"和"陰陽"為核心原則,重視"乾坤"和"八卦"在卦爻符號系統和宇宙圖景中的建構作用。"中正""中和""時中"是三種爻位論,同時是對"中"的人文價值理念的象數化,它們綜合起來均以"成既濟定"為基本指向。"成既濟定"是一種"天下和平"(普遍和諧)的理念在爻位論上的具體反映。在漢魏之際,漢易象數學在走向極致的同時走向了極端,并由王弼在方法論上完成了《周易》解釋從象數到義理的轉變。

The imagistic numerology of the late Han Dynasty is characterized by logicalization and systematization,with Zheng Xuan,Xun Shuang,and Yu Fan’s theories being three typical examples. Its deduction includes two logics: one proceeds from the Qian hexagram and the Kun hexagram to the twelve decreasing and increasing hexagrams,and then to the sixty-four hexagrams; while the other is the internal deduction of the Qian hexagram and the Kun hexagram within one hexagram. The construction of the imagistic numerology of the late Han Dynasty is based on both logic and method. The conception of the way of Heaven in this imagistic numerology uses"Heaven and Earth"and"Yin and Yang"as essential principles,and attaches importance to the constructive function of "Qian and Kun"and the "Eight Trigrams"in the hexagram-line symbolic system and world view. "Zhong-Zheng,""Zhong-He,"and "Shi-Zhong"are three kinds of line-position theory which show both the imagistic and numerological turn to the humanistic value. Between Han and Wei Dynasties,this imagistic numerology goes to the ultimate and also the extreme. Wang Bi uses the methodology of "meaning and principle"and completes the major transformation in Zhouyi exegesis from a focus on image and number to one on meaning and principle.