Letters 76.20

You may perhaps remember my saying that the things which have been generally desired and feared have been trampled down by many a man in moments of sudden passion. There have been found men who would place their hands in the flames, men whose smiles could not be stopped by the torturer, men who would shed not a tear at the funeral of their children, men who would meet death unflinchingly. It is love, for example, anger, lust, which have challenged dangers. If a momentary stubbornness can accomplish all this when roused by some goad that pricks the spirit, how much more can be accomplished by virtue, which does not act impulsively or suddenly, but uniformly and with a strength that is lasting!

Seneca, Letters to Lucilius 76.20, translated by Richard Mott Gummere