The world is getting older. A while ago there was a huge expansion of young people in third world countries. AIDS and contraception are curtailing that. In 1984 Japan had the youngest population in the developed world; by 2005 it had become the world's most elderly country. Soon it will become the first country where most people are over 50 years old. Japanese men can expect to reach 79 and women 86. But it it not just that the old aren't dying, it's also that the Japanese have practically given up having babies. The fertility rate is just 1.2 children per woman; A ratio of 2.1 is needed to maintain a steady population.
But it's not just Japan. The longevity revolution affects every country, every community and almost every household. Change is coming that will effect the economy, the family, politics and the world order.
This is frightening, especially for rich nations. In Germany, France and Japan, there are fewer than two taxpaying workers to support each retired pensioner. In Italy, the figure is already fewer than 1.3.
However, there might be a bright side. It isn't only pop singers like Mick Jagger and Tina Turner (who took to the stage in London, dancing in heels and a microskirt in her 70th year) who behave in their dotage like they did as teenagers. Last year we had the elderly Tom Watson leading in the Open and now Fred Couples a first round leader in the Masters. And millions of ordinary middle-class retired people continue working at everything from lucrative consultancies to teaching literacy or English as a foreign language. They are often more valuable than the young workers that the experts imagine are supporting them: in fact, the growing number of society's most qualified, most experienced individuals is a huge demographic dividend.
The idea of a retirement age was invented by Otto von Bismarck in the 1880s. When as chancellor of Germany he needed a starting age for paying war pensions, he chose the age of 65 because that was the age when ex-soldiers typically died. Today, women can expect nearly 30 years of retirement, and men 20 years.
Last night I watched an episode of the Swedish TV detective, Wallender. At 62 he is horrified that he will shortly have to retire. What's a man supposed to do? Plant potatoes and wait for the grim reaper?
A national do-it-yourself store has taken a lead by employing older men who are able to give advice about how to do jobs around the house. I know of doctors in their eighties leading teams in American hospitals. Indeed, some of my American colleagues were astonished that I had retired so early.
Some older people do need healthcare, but many others are fit, competent and self-sustaining. Across Europe, typically only one retired person in 20 lives in a care home. In the UK, of 10 million over-65s, just 300,000 (or 3%) live in care homes. What is to become of our older citizens?
Have you watched day-time TV? Recycled episodes of Poirot and Midsummer Murders, a grey haired Dick Van Dyke, children's cartoons, Escape to the country, Cash in the Attic, Antiques Road Show, Oprah, Rikki Lake, Judge Judy, Ugh! There has to be more in life.
To my mind, ageism in employment must stop. At 60 you can't do what you could at 40 and at 80 you're no longer 60. You do get tired. But mixing with people keeps you young. It's not that you need the money. Many people find the mortgage paid, children catered for, the pension sufficient. Your local hospital can't afford to employ a receptionist? Most volunteers could easily do the job. You may not be up to an 8 hour shift, but you could easily manage 2 or 3.
Many could do more. I find a couple of hours a week teaching the Fellows to be rewarding. In fact, I would happily do a clinic (unpaid) once a week as long as I could abstain from medical politics.
The elderly are an underused resource.