There has been a substantial increase in the length of human life. [I'll provide some statistics in a future version of this page.] The recent increases have involved both advanced and backward countries. [I use the word backward, because I think these countries should and will follow along a path very similar to that taken by the advanced countries.]

The largest increase in average longevity comes from the reduction in childhood mortality coming from public health measures and antibiotics. Better nutrition has also played a role. Young adult mortality has been reduced by the conquest of most infectious diseases, especially tuberculosis.

I think the reduction of childhood and young adult death has had a large psychological effect, although I have never seen a study of the phenomenon. When half of all children died in childhood, adults did not become so attached to an individual child - unless it was an only child. Children often experienced the deaths of brothers and sisters. Young adults expected that many of their contemporaries would die. Probably this made people take the Christian religion with its promises of immortality more seriously than people do today.

There has also been a substantial reduction in mortality of people over 60, over 70, over 80, over 90, and over 100. Last year (2002) was the first time I read of someone dying above 110 who was known for something other than having lived a long time. [The mathematician Leopold Vietoris died at almost 111. I'd read some of his work on topology.]

Much more interesting is the prospect of living in good health much longer than people can now expect. [From birth a girl can expect to live to be 80 and a boy to 75 - my 2002 age. I'm 80 now in 2007. These figures are based on present death rates at all ages and don't take into account improvements in medicine.]

Much greater longevity

  1. Existing longevity increases have concentrated property in the elderly. Had I died at the age my father died, my heirs would be richer. Many, perhaps most, American families accumulate equity in their homes, and have paid off their mortgages by the time they retire.
  2. Increased longevity will require an increase in the retirement age. This increase will be mitigated by advances in productivity and by the increasing employment of immigrants.
  3. A smaller fraction of a woman's life is taken up with children. This also applies to men but to a lesser extent. Imagine people living to 200 with only 25 years occupied with raising children. You still only get 2 children per woman if the population is to be stable.
  4. In a longer-lived society the ratio of adults to children will be larger. This could mean that young children could have all the adult attention from which they could benefit - maybe more.
  5. Unless something is done to mitigate the effect, society will increasingly be dominated by the very old. Maybe this will make it more difficult for new ideas to win support. Taking a favorable look at the same phenomenon, fads will win less support.
  6. Something, e.g. wealth taxes, will eventually be required to transfer wealth, e.g. homes, to younger generations.
  7. The present tax laws hinder transfer of wealth from parents to children. The amount that can be given per year from a parent to child without a special tax is in 2003 $11,000. The purpose of this restriction is to prevent avoidance of inheritance taxes. To put it bluntly, the Federal and State Governments are greedy. The consequences are not serious for the very rich, i.e. those with over $10 million, because there are gimmicks the tax advisors can help with. A current phenomenon is a great many middle income people who have paid off their mortgages cannot conveniently transfer money to their children that will permit them to buy homes. Many who bought homes in their 20s using the GI Bill and low interest rates have children in their 30s and 40s who cannot afford homes. This particular problem can be somewhat eased by removing the restrictions on gifts to children. Eventually, there should be a positive tax-benefit encouragement of gifts to children at least up to the cost of a home.
  8. Long distance space travel requires multi-generation voyages if present science is correct about the speed of light being a limitation. If we lived to 1,000 years, many other solar systems would be available without multi-generation voyages. Living 100,000 years might make the whole galaxy available.
  9. Increased length of life produces an increase in population proportional to the new length of life. It isn't exponential like an increase in the birth rate.
  10. People will have more than one career. Indeed it may become mandatory to retire from any particular job in 40 years.
  11. Increased length of life has caused an increased emphasis on safety. Firecrackers are forbidden. Cars become safer and safer. 40,000 people are killed in automobile accidents, but still it is one of the minor causes of death. If automobile accidents at the present rater were the only cause of death, Americans would have an average lifetime of 7,000 years. Now suppose that other causes of death were greatly reduced, so that people lived 1,000 years. Then automobile accidents would be one of the major causes of death, and there would be demands for very restrictive laws.
  12. Here are some hazards to life from an article by Bernard Cohen showing the relative safety of nuclear energy compared to other dangers. Note that the hazard from nuclear energy is less than any of the others.

Hazards to life

Hazards to life from Bernard Cohen, L.A. Times June 4, 1978
Risk: days of life expectancy lost by taking the risk
Riding in cars (10,000 miles/yr) 200
Not using seat belts 50
Driving small cars 50
Smoking one pack/day 2200
Overeating by 200 calories/day 400
Being one pound overweight 30
One diet drink/day 2.5
Fire 30
Drowning 40
Being poisoned 20
Choking on food 12
Being asphyxiated 7
Struck by falling object 6
Electrocution 6
Lightning 6
Being bitten by an animal or insect 0.3
Being murdered 90
Consuming electricity (if it were all nuclear) 0.05
Consuming electricity from coal 15
Air pollution (all sources) 25
Being male rather than female 2700
Remaining unmarried 1800
Working as a coal miner 1500

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