王陽明底「知行合一」說可上溯至孟子底「良知」學說。康德在〈論俗語所謂:這在理論上可能是正確的,但不切實際〉一文中則分別從道德學、國內法、國際法三個層面討論理論與實踐之關係。在道德底層面上,康德得到一項結論:凡是對於理論而言是正確的,對於實踐也必然有效。理論與實踐在道德中的這種一致性正是王陽明「知行合一」說,以澄清有關「知行合一」說的若干誤解。本文指出:儘管王陽明底「知行合一」說與「心即理」、「致良知」之說並非同時提出,但此三說在義理上是互涵的。
Wang Yang-ming's doctrine of the ”unity of moral knowledge and action” (chih-hsing ho-i) can be traced back to Mencius' theory of liang-chih (良知). Similiarly, Kant has discussed the relationships of theory to practice on three different levels in his article, ”On the Common Saying:' This May be True in Theory, but it does not Apply in Practice'”. He proposed the unity of theory and practice in moral philosophy. So in the light of Kant's doctrine of theory and practice, I interpret Wang's doctrine of the ”unity of moral knowledge and action” with a view to clarifying some misinterpretations of it. Thereby, I demonstrate that this doctrine is logically interconnected with Wang's other two doctrines, namely, the doctrine of hsin-chi-li (心即理) and that of chih liang-chih (致良知), although these tree doctrines were advanced by him different times.