For Americans, few decisions are as financially consequential as choosing when to take Social Security. Or as hard. While you can tap retirement benefits as early as age 62, the federal government offers big financial incentives to wait. The rules are complicated, however–books have been written on Social Security’s intricacies. And choosing to delay activation raises some arguably existential questions: If you maximize your benefit by waiting until age 70, what are you supposed to live on in the meantime? And what if you die earlier than you expected?