Two trajectories. A short comparison with a precise difference. The arrow (βέλος) flies on a single trajectory — straight, but blind and irreversible: once loosed, it cannot turn. The TERMmind (νοῦς) moves "otherwise" (ἄλλως): it can be cautious (εὐλαβεῖσθαι) and "turn about in inquiry" (περὶ τὴν σκέψιν στρέφεσθαι) — circle, weigh, draw back and approach from another side. And yet — here is the point — it moves "none the less" (οὐδὲν ἧττον) κατ’ εὐθύ, straight, to what is set before it (τὸ προκείμενον).

Circling is not wandering. The mind's roundabout moves are no deviation from the goal: circumspection and all-sided examination are precisely its way of going straight. The arrow is straight mechanically; the mind is straight despite the crookedness of its path — straight in the intention, not the trajectory. Marcus has just applied the same κατ’ εὐθύ to the sunbeam (08-57: "the ray goes κατ’ εὐθύ and braces against the obstacle, yet stands"): in both, straightness is the mark of the unswerving movement of the rational toward its own. The same thesis is unfolded in 05-14 (reason "makes its way to the end set before it," προκείμενον τέλος, and "right action" — κατόρθωσις — is named for the straightness, ὀρθότης, of its road). The governing discipline is action: to hold the bearing on the προκείμενον through all one's circumspection.