Letters 71.28

And so when one has just begun, or is on one’s way to the heights and is cultivating virtue, or even if one is drawing near the perfect good but has not yet put the finishing touch upon it, one will retrograde at times and there will be a certain slackening of mental effort. For such a man has not yet traversed the doubtful ground; he is still standing in slippery places. But the happy man, whose virtue is complete, loves himself most of all when his bravery has been submitted to the severest test, and when he not only, endures but welcomes that which all other men regard with fear, if it is the price which he must pay for the performance of a duty which honour imposes, and he greatly prefers to have men say of him: “how much more noble!” rather than “how much more lucky!”

Seneca, Letters to Lucilius 71.28, translated by Richard Mott Gummere