The Dao of Heaven is to be cheng; the Dao of man is to become cheng.
Cheng is usually translated as "sincere" (or as a noun, "sincerity"). However, Ziporyn suggests as equally valid for the use above "real", "integrated", or in the context of his overall theme, "coherent". I would like to suggest another possibility: "authentic".
Despite the incredible mess that humanity has created in its own little backwater of the Universe, the view from Dao tells us that all is nevertheless well. Dao has its own act together, and since there is really nothing that is not Dao, that means that even humanity has its act together. Yes, that is indeed an assertion hard to get one's mind around, but one that I think is unavoidable from the point of view of philosophical Daoism and absolutely necessary to the actual behaviorial outcomes that Daoism envisions as condusive of the greatest enjoyment of life. Wuwei (non-doing), ziran (spontaneity), and Zhuangzi's free and unfettered wandering are all predicated on this implicit trust in the ultimate 'rightness' of things as they are.
Is this a "belief" (something I usually eschew)? Perhaps; but if so, it is, I would suggest, one that naturally arises out of the life experience, and as such requires no defence. Is it a belief to say that life seeks to live? Perhaps; but that life lives requires no proof. (Just as knowing the happiness of fish is self-evidential and lies beyond proof.)
Cheng, in the case of Reality, is being real, a wonderful tautology, to be sure. In the case of humanity, however, it is to become real. Thus, I have suggested "authenticity" as an appropriate stand in. Authenticity is becoming who we are. Becoming who we are is much more a question of seeing and admitting to who we are than it is changing who we are, though the latter is understood to follow naturally from the former. Thus, cheng is "sincerity", honesty. We can see then how that cheng is a necessary requirement for self-cultivation, especially as that is facilitated by self-examination.
Cheng is also "integration", which is essentially Ziporyn's "coherence". The Dao of Heaven is the way all things fit together. All things fit together; this is so ‘true’ that to say it is to miss it. It could not be otherwise (from the point of view of Daoism). In the case of human subjectivity, therefore, it is similarly the realization of integration with the givens of life and the realities of one’s own unique existential expression. It is fitting in with the way things are, or appear to be (it does not matter which). It is thus first the illumination of one’s context (internal and external) and secondly the affirmation of that which is illuminated.
Cheng also implies the fulfillment of one’s potential. In seeing who we are and affirming who we are, we become more of who we are. What is that? For Daoism, it is certainly not realizing one’s “true nature”, for there is no such thing until one becomes it.
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