Triage of the work. The passage is a decision-procedure laid out in branches. The first question is sober self-assessment: "is my διάνοια sufficient for this?" If yes — take it up and work. If not — two honest branches: yield the work to one who will do it better (παραχωρῶ — with no jealousy for precedence), or — if the task is such that yielding it TERMis not fitting (μὴ καθήκῃ: some works cannot be handed over, and an emperor has many) — do what you can, taking a helper. Self-regard enters the calculation in neither branch: what matters is the deed, not the doer.
The mind as issued equipment. The ground of this indifference to precedence lies in the status of the mind itself: it is "an instrument given by the TERMnature of the Whole" (ὡς ὀργάνῳ παρὰ τῆς τῶν ὅλων φύσεως δοθέντι). My reason is not private property to be vain of, but issued equipment for which I answer to the issuer. Hence too the remarkable formula about the helper acting "κατὰ πρόσχρησιν τοῦ ἐμοῦ TERMἡγεμονικοῦ" — "making use of my ruling part as well": even when another leads, my ἡγεμονικόν remains material for the common act. The hierarchy of executors is indifferent; the instruments add up.
The single measure. The close draws everything to one criterion: εἰς τὸ κοινῇ χρήσιμον καὶ εὐάρμοστον — "to what is commonly useful and well-fitting" (κοινωνία, κοινῇ — the communal lexicon; for the concept see τὸ κοινωνικόν). To accomplish by one's own strength or another's is indifferent; only the aim, never the manner, could be shameful. The nearest parallel is 7.7: "do not be ashamed to be helped: your task is to do your duty, like a soldier at the storming of a wall"; cf. 4.12 (readiness to change course at a just correction) and 8.16 (to change one's mind at another's correction is also a free act). The governing discipline is action; the sustaining one, assent (the exact estimate of one's powers).