The Doctrine of the Mean (Zhōngyōng 中庸) — Heaven-Conferred Nature, the Mean, and Sincerity

N=1 fine-grained distillation. Source: James Legge, The Doctrine of the Mean, in The Four Books (Commercial Press bilingual edition), full text at Internet Archive — The four books (fourbooksconfuci00leggiala). Only the numbered canonical translation paragraphs are extracted (Legge's commentary and interleaved Chinese excluded). Quote anchors are working text pending Phase 7 char-for-char verification. Methodology & tags: ../00-methodology.md. Citation: Doctrine of the Mean <ch>:<para> (Zhu Xi's chapter division).

Book's role

The Doctrine of the Mean is the Four Books' metaphysical frame: it grounds the moral life in a Heaven-conferred nature, names the Path of duty as following that nature, and develops the two great doctrines unique to this text — equilibrium-and-harmony (zhongyong, "the Mean") as the root and path of all human action, and cheng (sincerity / integral truthfulness) as "the way of Heaven" and the self-completing power of moral being.

Atomic statements

DM-C1: What Heaven confers is the nature; following the nature is the Path; regulating the Path is instruction. (FOUNDATIONAL / HEAVEN+SELF)

Doctrine of the Mean 1:1: "What Heaven has conferred is called THE NATURE; an accordance with this nature is called THE PATH of duty; the regulation of this path is called INSTRUCTION."
Stance: assert · Importance: core · Untranslatable: tian (Heaven), the Heaven-conferred xing (nature)

DM-C2: Before the feelings stir, the mind is in EQUILIBRIUM; when stirred and acting in due degree, there is HARMONY; equilibrium is the great root, harmony the universal path. (FOUNDATIONAL / HARMONY+SELF)

Doctrine of the Mean 1:4: "While there are no stirrings of pleasure, anger, sorrow, or joy, the mind may be said to be in the state of EQUILIBRIUM. When those feelings have been stirred, and they act in their due degree, there ensues what may be called the state of HARMONY. This EQUILIBRIUM is the great root from which grow all the human actings in the world, and this HARMONY is the universal path which they all should pursue."
Stance: assert · Importance: core · Untranslatable: zhong (equilibrium/the Mean), he (harmony)

DM-C3: Let equilibrium and harmony exist in perfection, and a happy order prevails throughout heaven and earth, and all things flourish. (FOUNDATIONAL / HARMONY+HEAVEN)

Doctrine of the Mean 1:5: "Let the states of equilibrium and harmony exist in perfection, and a happy order will prevail [throughout heaven and earth, and all things will be nourished and flourish]."
Stance: assert · Importance: supporting

DM-C4: Sincerity is the way of Heaven; the attainment of sincerity is the way of men. (FOUNDATIONAL / HARMONY+HEAVEN)

Doctrine of the Mean 20:18: "Sincerity is the way of Heaven. The attainment of sincerity is the way of men. He who possesses sincerity is he who, without an effort, hits what is right… He who attains to sincerity is he who chooses what is good, and firmly holds it fast."
Stance: assert · Importance: core · Untranslatable: cheng (sincerity / integral truthfulness)

DM-C5: Sincerity is that whereby self-completion is effected; it is the end and beginning of things — without sincerity there would be nothing. (FOUNDATIONAL / HARMONY+SELF)

Doctrine of the Mean 25:1–2: "Sincerity is that whereby self-completion is effected, and its way is that by which man must direct himself… Sincerity is the end and beginning of things; without sincerity there would be nothing. On this account, the superior man regards the attainment of sincerity as the most excellent thing."
Stance: assert · Importance: core · Untranslatable: cheng

DM-C6: The man who attains sincerity chooses what is good and firmly holds it fast — sincerity is achieved by choosing the good. (OPERATIONAL / SELF+YI)

Doctrine of the Mean 20:18 (continued): "He who attains to sincerity is he who chooses what is good, and firmly holds it fast."
Stance: assert · Importance: supporting · Untranslatable: cheng attained by choosing shan (the good)

Step 4 — Clusters

Cluster	Atomic statements	Intent
Heaven-conferred nature & path	C1	Morality is rooted in a nature given by Heaven and followed as the Path
Equilibrium and harmony	C2, C3	The Mean is the root and universal path; perfected, it orders the cosmos
Sincerity (cheng)	C4, C5, C6	Sincerity is Heaven's way and the self-completing, world-grounding power

Step 5 — Internal tensions

None. Cheng "of Heaven" (effortless, C4) and cheng "attained by men" (by choosing the good, C6) are two modes of one reality — the sage's spontaneity and the learner's effort — not a contradiction.

Step 6 — Synthesized book principles

DM-P1: Morality is rooted in a Heaven-conferred nature

What Heaven confers is the nature; following that nature is the Path of duty; regulating the Path is instruction. The moral order is neither invented nor commanded from outside but is the cultivation of a nature already given.

Tier: FOUNDATIONAL · Domain: HEAVEN+SELF · Covers: C1 · Evidence: Doctrine of the Mean 1:1 · Untranslatable: tian, xing

DM-P2: Equilibrium and harmony are the root and path of all action

Equilibrium (the unstirred mind) is the great root; harmony (the feelings acting in due degree) is the universal path. Perfected, they bring a happy order to heaven, earth, and all things — the doctrine of the Mean.

Tier: FOUNDATIONAL · Domain: HARMONY+HEAVEN · Covers: C2, C3 · Evidence: Doctrine of the Mean 1:4–1:5 · Untranslatable: zhong, he, zhongyong

DM-P3: Sincerity (cheng) is the way of Heaven and the self-completing power of being

Sincerity is the way of Heaven, and to attain it is the way of men; it is "the end and beginning of things — without sincerity there would be nothing," and self-completion is effected through it.

Tier: FOUNDATIONAL · Domain: HARMONY+SELF · Covers: C4, C5 · Evidence: Doctrine of the Mean 20:18, 25:1–2 · Untranslatable: cheng

DM-P4: Sincerity is attained by choosing and holding fast the good

The one who attains sincerity "chooses what is good, and firmly holds it fast" — sincerity is not mere feeling but the steady choosing of the good.

Tier: OPERATIONAL · Domain: SELF+YI · Covers: C6 · Evidence: Doctrine of the Mean 20:18 · Untranslatable: cheng

Step 7 — Traceability

Principle	Atomic statements	Passages
DM-P1	C1	Doctrine of the Mean 1:1
DM-P2	C2, C3	Doctrine of the Mean 1:4–1:5
DM-P3	C4, C5	Doctrine of the Mean 20:18, 25:1–2
DM-P4	C6	Doctrine of the Mean 20:18

Step 8 — Quality

Coverage: the Doctrine of the Mean's three load-bearing doctrines — the Heaven-conferred nature (ch.1), equilibrium-and-harmony (ch.1), and cheng (chs.20–26) — are each captured. The long central chapters elaborate cheng and the sage but do not add a distinct compass-level principle beyond these.
Orphaned: the historical/illustrative chapters (e.g. on filial kings, the ways of the junzi in detail) are not separately distilled.
Principles: 4 (within range).
Traceability: 100%.

Step 9 — Validation

Standalone comprehension (frame-independent): DM-P2 (balance/the Mean) and DM-P4 (steadily choosing the good) read as intelligible to an outsider; "the Mean / due measure" is a strong convergence candidate (cf. Aristotle's mean, many wisdom traditions). Two warrant-level flags for the Atlas: (1) DM-P1 grounds morality in a Heaven-conferred nature — close to natural-law/imago-Dei talk in claim (a given moral nature), but the warrant (an impersonal tian that confers without commanding or revealing) diverges from a personal creator; (2) DM-P3's cheng — sincerity as a near-cosmic, self-completing, world-grounding power ("without sincerity there would be nothing") — is a WEAK-distinctive Confucian jewel with no exact analogue elsewhere: it makes integral truthfulness an ontological, not merely ethical, reality.