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Anger unfolds in stages: an involuntary first jolt (the 'first movement') that even the wise feel, then the mind's assent to the judgment 'I have been wronged and ought to retaliate', then a runaway state in which reason is overthrown. Only the second stage is under our control, so the remedy is to intervene at the moment of assent, before the judgment is ratified.
Seneca argues against the view that anger in measured doses fuels courage or justice. Once reason admits a passion it can no longer set the limit, because the passion is stronger than the thing trying to govern it. Whatever anger supposedly achieves, reason can achieve more reliably on its own terms, by punishing as a physician treats a patient, without heat.
The best cure for anger is postponement, since its force comes from the first rush and fades if not acted on. By refusing to act or judge while provoked and waiting until the swelling subsides, one lets the false judgment of injury be re-examined before it turns into action.
Before condemning an offender, ask whether you have done the same thing or would have done it in their position. Since no one is without fault, anger at others' failings is inconsistent. Recognizing shared human frailty turns indignation into leniency, and the reasonable response to a common condition is pardon, not rage.
Each night, review the whole day and ask: what bad habit did I cure today, what fault did I resist, in what way am I better? Seneca describes doing this after the lamp is out, hiding nothing from himself. Anger shrinks when it knows it must appear before a judge every evening.
Angry with a slave, Plato stood frozen with his arm raised to strike. When a friend asked what he was doing, he said he was punishing an angry man, meaning himself. He later handed the punishment over to someone else because he did not trust his own judgment while angry, showing that anyone who administers correction must first be free of the passion.