I am quite taken with this idea of cheng as offering significant insight into the process of self-cultivation. It is primarily a Confucian idea, but I think it also provides a means to better understanding the model of philosophical Daoism. It needs to be said, however, that my exploration of it here is not necessarily a faithful representation of cheng in the documents themselves or of Ziporyn's analysis of them. What I write here might better be described as a response, and then not always one that has properly understood the original intended meaning or appreciates it when it has. No matter — onward.
We have already discussed Ziporyn's quote from "The Doctrine of the Mean"; I offer it again now with his annotations: "Unseen coherence means self-completion [spontaneous coming into true being, being perfect as oneself]. Dao means self-guidance [auto-guidance, spontaneous nondeliberate directedness]. For unseen coherence is the end and beginning of each thing. Without unseen coherence there is no thing. This is why the exemplary person values unseen coherence. Unseen coherence not only brings the self to completion, but also brings things to completion. Completion of oneself is benevolence; completion of things is wisdom. These are the Virtuosities ['virtues', de] of the inborn nature, the Dao of joining the inner and the outer . . ."
I understand "bringing things to completion" as referring to the creation of a harmonious society and by extension, a harmonious world-environment. The self-cultivation of Confucianism, though it may have its beginning in the individual, intends the harmonization of the entire human enterprise, and this includes its environmental context. Is this also the Daoist vision? I think so, but it feels no need to articulate the extended goal since it takes more seriously the idea that these things arise spontaneously as one harmonizes oneself. Confucianism and Daoism are essentially on the same page in terms of desired outcomes, but philosophical Daoism refrains from political ambitions which, in the end, can only lead to the imposition of agendas, and these typically lead to just more coercion.
There is a great deal to unpack here, and this will have to be over the course of several posts.
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