“if a person could develop peace within themselves—if they could achieve apatheia, as they called it—then the whole world could be at war, and they could still think well, work well, and be well. “You may be sure that you are at peace with yourself,” Seneca wrote, “when no noise reaches you, when no word shakes you out of yourself, whether it be flattery or a threat, or merely an empty sound buzzing about you with unmeaning sin.” In this state, nothing could touch them (not even a deranged emperor), no emotion could disturb them, no threat could interrupt them, and every beat of the present moment would be theirs for living.”