Imagine immortality, where a marriage of fifty years feels like a one-night stand. Imagine the world more crowded and desperate every century. Imagine changing religions, homes, diets, careers, until none of them have any real value. Imagine your loves and hates and rivalries and victories, played out again and again until life is nothing more than a melodramatic soap opera. Until you regard the birth and death of other people with no more emotion than the wilted cut flowers you throw away.