How to Say the Unsayable Dao——An Linguistic Analysis of Lao-zi's Dao

In light of hermenuetical thought of Dai Zhen,a philosopher in Qing Dynasty,there are multi-levels of meaning in Lao-zi's core notion of Dao: The linguistic analysis of concept tells us that the original and the normative are fundamental contents of Lao-zi's Dao.Furthermore,the original can be understood from two perspectives,ontology and evolution theory,and the normative has two aspects,the Dao of Heaven and the human Dao.