Living a long time is one of our deepest wishes, and medical and economic progress offers the hope that it will be fulfilled. Some scientists say that the average human lifespan could reach 90 years or more by mid-century. But what if our wish is granted? What good is a longer life if we cannot maintain our standard of living?
The fundamental difficulty in planning for enhanced longevity is that we do not know whether it will really happen. Life expectancy might well be only 80 years by mid-century – about where it is now in advanced countries – if medical progress is disappointing or is offset by new threats or hazards. If we make provisions for long lives that are cut short, we will have wasted huge amounts of precious economic resources. But if we fail to make provisions for lives that are longer, many elderly people will be condemned to poverty.