How does Epictetus say we should respond when someone insults or wrongs us?

Epictetus's argument starts from a claim about the other person's mind, not about yours. When someone harms you or speaks badly of you, he says, remember that "he acts or speaks from a supposition of its being his duty" (Handbook 42). The insult, from the inside, feels justified to the person giving it. He cannot act on what seems right to you, only on what seems right to himself.

From there Epictetus draws a conclusion that most people resist. If the other person is judging from a false appearance, "he is the person hurt, since he too is the person deceived" (Handbook 42). He gives an analogy: if someone takes a true proposition to be false, the proposition suffers nothing. The person who is wrong about it is the one who suffers, because he is walking around with a false belief. An insult works the same way. The words do not damage you. The false judgment behind them damages the person who holds it, because a distorted view of the world is itself a kind of harm to the one who holds it.

That misses what Epictetus is actually claiming. He is not offering a mood hack. He is applying the dichotomy of control that opens the Handbook: some things are in our power and some are not, and reputation is explicitly listed among the things that are not (Handbook 1). Your reputation, how you look in another person's eyes, was never yours to begin with. It belongs to them, since it is their judgment. So when someone insults you, they are not touching anything of yours. They are exercising a judgment that belongs to them, badly.

This is also why Epictetus does not tell you to retaliate, defend your name, or even feel wounded and suppress it. His conclusion is that you will "meekly bear a person who reviles you," and the internal move he prescribes is simple: say to yourself, "it seemed so to him" (Handbook 42). That sentence is not resignation. It is an accurate description of what happened: a person acted on his own mistaken appearance, and nothing that is actually yours, your judgments, your choices, your character, was touched by it.

The deeper reason this matters is in Zeus's speech in the Discourses. Epictetus imagines Zeus explaining why he could not make the body and property free from hindrance, but gave human beings something else instead: "this faculty of pursuing an object and avoiding it, and the faculty of desire and aversion, and, in a word, the faculty of using the appearances of things." Take care of that faculty and treat it as your only real possession, and "you will never be hindered... you will not lament, you will not blame, you will not flatter any person" (Discourses I 1). Reputation was left outside that gift on purpose. It was never going to be fully yours, so building your peace on it was always going to fail.

None of this says the other person did nothing wrong. Epictetus is not excusing bad behavior. He is locating where the actual damage lands, and it is not on you. What changes for someone who takes this seriously is where they put their attention after being insulted. Instead of building a case for why they were wronged, they ask a narrower question: did anything that is actually mine, my judgment, my choice, get damaged here. Usually the honest answer is no.

A concrete practice follows directly from the text. The next time someone insults you, before you respond, say the line to yourself: it seemed so to him. Not as a slogan to make the sting go away, but as a true description of what just happened. Then decide, separately, whether anything up to you, your own action, needs correcting.