An axiom and its practical corollary in a single line. Two short sentences are locked together as premise and consequence. The premise is the fundamental Stoic DOGMAaxiom of sociability: Οἱ ἄνθρωποι γεγόνασιν ἀλλήλων ἕνεκεν, "human beings are born for one another." From the natural mutual belonging of rational beings Marcus draws not sentimental love but a strict practical fork with respect to the one who errs: ἢ δίδασκε ἢ φέρε — "either teach, or bear."

Teach or bear. The fork is exhaustive. If the neighbor errs from ignorance, it is one's task to set him right by instruction (διδάσκειν); if he cannot be set right (or not by you, or not now), what remains is to bear with him (φέρειν) without anger, since anger at a fellow-member contradicts the very same axiom. A third option — to hate, to retaliate, to turn away — the nature of those born-for-one-another does not provide. The formula recurs in Marcus as a ready instrument: cf. 5.28 (toward the ill-smelling man, not anger but "show him his error, admonish him"), 9.11, 11.13, 11.18. The same premise ἀλλήλων ἕνεκεν also stands in 8.56 (where, however, the conclusion runs the other way: another's vice does not harm me). The governing discipline is action: one's stance toward a fellow-member of the common body.