Why do so many of us not give ourselves permission to be...

Why do so many of us not give ourselves permission to be alive until we are absolutely assured that we will die? ...If we are not in [this present millisecond of life and conscious experience], we are not alive; we are merely thinking our lives. Yet we have seen so many die, looking back over their shoulders at their lives, shaking their heads and muttering in bewilderment, "What was that all about?"