Seneca identifies anticipatory anxiety as a major source of unnecessary suffering. Most of our worries never materialize, yet we suffer as if they're already happening. This creates a cruel irony where we experience more pain from imagined futures than from actual present circumstances. The anxiety about potential job loss can be worse than actual unemployment; fear of rejection can be more painful than actual rejection; worry about illness can be more debilitating than actual sickness. By recognizing this pattern, we can reduce suffering by staying focused on present realities rather than possible futures, preparing appropriately for challenges without tormenting ourselves with endless 'what if' scenarios.