Letters 76.35

Hence, the wise man accustoms himself to coming trouble, lightening by long reflection the evils which others lighten by long endurance. We sometimes hear the inexperienced say: “I knew that this was in store for me.” But the wise man knows that all things are in store for him. Whatever happens, he says: “I knew it.” Farewell.

Seneca, Letters to Lucilius 76.35, translated by Richard Mott Gummere