李鼎祚的《周易集解》，為目前保存漢《易》的主要文獻，也是對漢《易》認識的最佳進路。《易》卦的陰陽爻，以及其爻所處的爻位，為構成符號意象思維的重要成份，特別表現在爻位的「當」、「應」上。李道平的爻位觀，在「當」與「應」方面，其龐富多元之內涵，已非《易傳》或漢魏某家之說所能牢籠。李氏在爻位關係的理解或釋義的運用上，「當」與「應」的關係，往往相伴互現，而且重視正應的認識。同時，除了一般的「當」、「應」關係外，李氏也提到特殊的「當」、「應」關係，運用了動態的、積極的爻變手法，包括之正、升降等說，復求爻位的歸正，並反映出李氏同虞翻一樣對成既濟的理想定勢之期盼。李氏對不義之應作了次級或負面的認定，表現出他對良善本質與規律有序的高度肯定，對事物發展與定位的正當性作積極的確定。但是，對於其特殊的「當」、「應」說與爻變主張當中，仍可看到運用上的矛盾附會之現象，也看出這套釋義系統不能通解的侷限與困境！

Zhouyi Jijie by Li Dingzuo is the main literature of Hanyi and provides the best way to grasp the main ideas of it. The yin yao and yang yao of I-diagrams and their yao-wei （the position of component lines） are important elements of symbols and images, especially in terms of Dang and Ying. Li Daoping developed rich and diverse theories on Dang and Ying, which could no longer be covered by the content of I-zhuan or theories of any philosophers in Han or Wei Dynasty. Li proposed that Dang and Ying usually manifest at the same time and put emphasis on the concept of Zheng-Ying. In addition to regular Dang and Ying, he explored special Dang and Ying. By using dynamic and active yao-bian methods, including Zheng, and Sheng-Jiang , Li aimed to make yao-wei return to proper Dang and Ying, which suggested that he, like Yu-fan, longed for the idealism and stability of Jiji-gua. Li held a negative attitude towards bu-yi-zhi-Ying （non-rightous Ying）, demonstrating his high value on virtue, harmony and order. Despite the strengths of his theories, Li sometimes contradicted himself in the applications of his theories on special Dang and Ying, which showed the limitations of his theories.