Book VI · 52
It is in our power to have no opinion about a thing, and not to be disturbed in our soul; for things themselves have no natural power to form our judgments.
We need not form any opinion about the thing in question or be harassed in soul, for Nature gives the thing itself no power to compel our judgments.
Marcus Aurelius, Meditations VI.52. Translated by George Long (1862). The Stoic Library.