The reader might have noticed that these posts about cheng (sincerity, honesty, authenticity) have been more about Mencius' take than that of the Liji; this is because Ziporyn introduces the latter with the former. To this writer, the exploration of the meaning of cheng is profitable irrespective of which philosophy provides us access. In other words, I am more interested in the ideas than I am in their source.
Ziporyn finds in the Liji's sense of cheng "a newly appropriated subjective form of ironic intelligibility as a hiddenness that is indirectly expressed in all actions, and hence omnipresent in that sense." He calls this sense of cheng an "unseen coherence". This is the folding of the ironic Dao of Daoism into the otherwise non-ironic Dao of Confucianism. The question is: How do we make sense of the world (so as to know how to live) when we admit to the ultimate unintelligibility of the world (the ironic Dao)? The “Doctrine of the Mean” and “The Great Learning” of the Liji answer this question by admitting that cheng spontaneously arises out of the nature of humanity and the world and is thus rooted in the "hidden", and not in an articulable analysis of the world which we subsequently follow. In other words, we realize cheng by letting it happen rather than by following some rationalized schema of our understanding of the nature of the world. This is a huge concession on the part of Confucianism, and the antithesis of Xunzi’s approach.
In this, Ziporyn sees the “Doctrine of the Mean” as going beyond Mencius and “The Great Learning” to a cheng with "a metaphysical twist": "Unseen coherence (cheng) means self-completion. Dao means self-guidance. For unseen coherence is the end and the beginning of each thing. Without unseen coherence there is no thing." Cheng spontaneously happens, arising out of that which cannot be articulated. This is the position of philosophical Daoism. But here it is given a moral interpretation. The text continues: "This is why the exemplary person values unseen coherence. . . . Completion of oneself is benevolence; completion of things is wisdom. These are the Virtues [de] of the inborn nature, the Dao of joining the inner and the outer . . ."
Because he gives it a moral meaning (benevolence spontaneously happens), we can say that this "twist" is "metaphysical". Daoism, on the other hand, though it does not dispute this outcome of spontaneity, does not assert it either, or require that it be so; whatever happens is so. In this sense, philosophical Daoism's reliance on spontaneity is non-metaphysical.
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