Since the major absorption of scientific method into the research and practice of medicine in the 1860s, the longevity curve, at least for the white population in industrial countries, took off and has continued fairly constantly. That has been on the whole a benign result, and has begun to introduce the idea of tolerably good health as one of the basic Human Rights. But one now reads of projections to 200 years, and perhaps more. The economic, social and human costs of the increasing fraction of very elderly citizens have begun to be noticed already.
To glimpse one of the possible results of the continuing projection of the longevity curve in terms of a plausible scenario: The matriarch of the family, on her deathbed at age 200, is being visited by the surviving, grieving family members: a son and a daughter, each of age of about 180, plus /their/ three "children" , around 150-160 years old each, plus all their offspring, in the range of 120 to 130, and so on..... A touching picture. But what are all the "costs" involved?