Wonhyo's system of thought is structured around the concept of "one mind," as illustrated in his commentaries on the Awakening of Faith. "One mind" is another term for the mind of all sentient beings, a mind intrinsically pure and unchanging, but appearing externally to be impure and ephemeral. Even though every deluded thought arises from the mind, it is that same mind that simultaneously provides the capacity to achieve enlightenment. Wonhyo explains how this seemingly paradoxical achievement is possible using a three-fold structure to illustrate the experience of original enlightenment, non-enlightenment, and actualizing enlightenment, not as discrete entities, but as mutually contingent tensions. Original enlightenment is the theoretical base for enlightenment; non-enlightenment is a misconception about the nature of original enlightenment; and actualizing enlightenment is the incitement to practice. Practice here is based on the conditional definition of non-enlightenment, that is, the insubstantiality of defilements. Practice, therefore, does not involve removing something; rather, it is the creation of the correct knowledge that the defilements we experience in daily life are unreal. The distinction Wonhyo draws between original and non-enlightenment, and the attempts he makes to integrate the two, prepare the foundation for assertions of the universality of Buddhahood in later East Asian Buddhism. The Awakening of Faith itself originally provided the conceptual frame for this notion, but it was Wonhyo's elaboration in his commentary to that treatise that provided a more coherent interpretation of this construct and proposed a comprehensive solution to the tensions inherent in the definition of enlightenment in Buddhist history. This elaboration helped to establish a unique cognitive framework for East Asian Buddhism and made Wonhyo's commentary one of the most influential texts in the East Asian Buddhist tradition.
