Guesswork against inspection. The passage opens with a rhetorical question: τίς ὑπονοίας χρεία — "what need of surmise (ὑπόνοια), when it is open to you to look (σκοπεῖν) at what must be done?" ὑπόνοια is suspicion, conjecture, the thought that runs "underneath" things; against it is set a direct look at the matter. Marcus does not forbid doubting — he forbids guessing where one can investigate. What is to be inspected is τί δεῖ πραχθῆναι, "what must be done": a descriptive stand-in for καθῆκον, the term itself being absent here.

A three-branch algorithm. What follows is a procedure rarely set out so mechanically in Marcus:

1. You see clearly (συνορᾷς) — go that way εὐμενῶς and ἀμεταστρεπτί, "graciously" and "without turning round." Both adverbs matter: without irritation, and without looking back at the options forgone.
2. You do not see — ἐπέχειν, "hold off," and use the best advisers. Note that a technical term of the school is taken up: ἐποχή, the suspension of assent, is carried over from epistemology into practical decision.
3. Circumstances resist — go forward κατὰ τὰς παρούσας ἀφορμὰς λελογισμένως, "on the resources at hand, with reasoning," holding to τὸ φαινόμενον δίκαιον — "what appears just." The third branch is the reserve-clause in action: the impulse is not cancelled by the obstacle but re-set upon what remains possible (cf. 6.50).

A practical fallibilism. The formula τὸ φαινόμενον δίκαιον is the key one: not certainty is required, but the best available appearance of the just. Hence the justification: ἄριστον γὰρ κατατυγχάνειν τούτου, ἐπεί τοι ἥ γε ἀπόπτωσις ἀπὸ τούτου ἐστίν — "best is to hit this, since a falling-short is precisely a falling away from it." The only real failure is to fall away from the just; and so aiming at it cannot be a mistake (cf. 8.32 — the external does not prevent acting justly). Note that the whole passage rests on justice, yet the word δικαιοσύνη is never uttered in it: only the adjective (τὸ δίκαιον) and, twice, the pronoun τούτου.

Four predicates in pairs. The closing portrait is built from two pairs of apparent opposites: σχολαῖον — εὐκίνητον ("unhurried" and "easily moved"), φαιδρόν — συνεστηκός ("bright" and "collected"). Ordinarily these exclude one another: the unhurried man is slow, the cheerful man scattered. He who TERMfollows λόγος in all things dissolves the opposition — not by balancing extremes, but because both qualities follow from one thing: he has neither haste nor disarray, because the decision has already been made by procedure. The governing discipline is action, the sustaining one assent.

A note on the tagging. Exactly one term is marked in the text of this passage — TERMλόγος — and that is not an oversight but the consequence of the strict-by-word rule. The concepts the passage rests on are all named descriptively: justice by an adjective (τὸ φαινόμενον δίκαιον, not δικαιοσύνη); the appropriate by the phrase τί δεῖ πραχθῆναι (not καθῆκον); the reservation by the very construction of the third branch (the word ὑπεξαίρεσις is absent); the available by the participle πάρουσαι with ἀφορμαί rather than the substantivized τὸ παρόν. All four therefore stand here, in the commentary, and not in the text or the frontmatter. Separately: σκοπεῖν ("to inspect") is not σκοπός ("the mark aimed at"), despite the shared root; there is no connection of sense.

A note on Long's version. The clause ἐπεί τοι ἥ γε ἀπόπτωσις ἀπὸ τούτου ἐστίν is rendered freely by Long: "if thou dost fail, let thy failure be in attempting this" — an imperative in place of a statement. Rogovin is nearer the letter («уклонение от него — наихудшее»), though he adds an evaluation the Greek does not have. Long also reduces εὐμενῶς ("graciously") to "content"; the modernization restores it.