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If it is not right, do not do it: if it is not true, do not say it.
— Marcus Aurelius · Meditations

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The saying pairs a rule for action with a rule for speech: refuse wrongdoing and refuse falsehood. Both depend on checking what one is about to contribute to the world. Integrity is presented as restraint, with some things better left undone or unsaid.
Context reviewed