Mosaic from the Villa dei Casale, Piazza Armerina, Sicily. 3-4th century CE.

CV. On Facing the World with Confidence

Nothing, however, will help you so much as keeping still –talking very little with others, and as much as may be with yourself. For there is a sort of charm about conversation, something very subtle and coaxing, which, like intoxication or love, draws secrets from us. No man will keep to himself what he hears. No one will tell another only as much as he has heard. And he who tells tales will tell names, too. Everyone has someone to whom he entrusts exactly what has been entrusted to him. Though he checks his own garrulity, and is content with one hearer, he will bring about him a nation, if that which was a secret shortly before becomes common talk.

Seneca Epistles 93-124, Translation by Richard Gummere. Loeb Classical Library.