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 canceled 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 vocabulary. 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 παροῦσαι with ἀφορμαί rather than the substantivized τὸ παρόν. Of the Stoic technical terms only TERMλόγος is named outright.

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.