Seneca’s injunction begins in the Stoic conviction that character is crafted one day at a time. In his Letters to Lucilius, he urges rehearsals of adversity and voluntary discomfort—not to court misery, but to tame it before it arrives. By training desire and fear in controlled settings, the mind learns to remain steady when life becomes unsettled. Thus, preparation is less about hoarding plans and more about shaping the person who will face events. From this vantage, the soul becomes a disciplined instrument, tuned for fate’s changing weather. [...]