Seneca isn't simply saying that hard times build character—he's making a muscular claim about the *mechanism* of growth, comparing mental development to physical conditioning. The crucial difference is that he treats difficulty not as an unfortunate obstacle but as the actual *medium* through which the mind becomes capable, much as a blacksmith's iron grows stronger only through repeated hammering. When you struggle through a problem at work that initially seems beyond you, you're not just solving that one problem; you're literally rewiring your capacity to handle complexity itself. It's why people who've weathered genuine hardship often possess a quiet confidence that no amount of smooth success can manufacture.