A syllogism on tirelessness. Three steps converging on a paradox. (1) "No one tires (κάμνει) of receiving benefit (ὠφελούμενος)" — self-evident: benefit is received gladly, without fatigue. (2) "But benefit (ὠφέλεια) is DOGMAan act TERMκατὰ φύσιν" — the Stoic definition: useful is what accords with nature, and for a rational-social being nature is to do good. (3) The reversing conclusion: "do not tire of receiving benefit — DOGMAin the very act of benefiting others (ἐν ᾧ ὠφελεῖς)."

The giver = the receiver. The trap is disarmed by a swap of roles: ordinarily "tiring of doing good" seems natural (strength runs out, thanks fail — cf. 7.73). Marcus shows this to be a category error: in benefiting, you do not spend but receive benefit — for an act is by its nature a good for the agent (DOGMAanother's good is your own, as in 7.13: the limb, serving the whole, serves itself). To tire of doing good is like tiring of receiving: logically impossible, once the nature of the act is grasped. Whoever is wearied by good deeds has simply failed to notice that all this while he was receiving, not giving. The strict term TERMφύσις is in the text. The discipline is action.