Extending human life expectancy is not a new story. When our genes evolved thousands of years ago, it was not in the interests of the species for people to live past child-rearing, as resources such as food were in very short supply. So a thousand years ago, human life expectancy was in the 20s.
It was only 37 in 1800. In the West it is now pushing 80, and we have been adding about three months each year for the past several decades.
This progression is about to go into high gear. Until recently, health and medicine was a hit-or-miss affair. We would discover interventions that had benefits but also many side effects. We did not have the means to design interventions, but that is changing.
The breakthrough in stem cell bio-logy offers just one example of the progress. With the completion of the human genome project in 2003 and the advent of techniques such as RNA interference, which can turn off the genes that promote disease and ageing, medicine has transformed itself into an information technology.
It is now subject to the “law of accelerating returns” — a doubling of capability (for the same cost) each year.
Technologies to reprogramme the “software” — genes — underlying human biology will be 1Â 000 times more powerful in a decade, and a million times more powerful in two decades. We will be adding more than a year every year to our remaining life expectancy only 15 years from now. That will be a tipping point in life extension.
Within a couple of decades, we will have “nanobots” in our blood stream, basically small robots the size of blood cells, that will keep us healthy at the cellular and molecular level.
There are already dozens of successful experiments with a first generation of such devices in animals. One scientist cured type-I diabetes in rats with a blood cell-sized device, and scientists at MIT have microscopic devices that can scout out cancer cells in the bloodstream and destroy them. In 25 years these devices will be a billion times more powerful than they are today.
The prospect of dramatically reducing the death rate troubles observers who worry about issues such as overpopulation and depletion of natural resources. Indeed, if there was radical life extension and no other changes, it would lead to unsustainable stresses. But these same technologies will dramatically change the resource equation as well.
Take energy, for example. We are awash with it. We have 10Â 000 times more sunlight than we need to meet 100% of our energy needs. But we cannot capture sunlight with sufficient efficiency today because solar panels are still an old industrial technology. But nanotechnology will result in inexpensive and highly efficient solar panels that will easily capture the one part in 10 000 of the sunlight needed to replace fossil fuels. I believe that will happen within 20 years.
Emerging technologies can recycle dirty water into clean water at extremely low cost. About 80% of disease in the developing world comes from dirty water. Nanotechnology will also enable the production of food, modules to build housing, and manufacture clothing and the other staples of life, at extremely low cost.
One concern is that a human life span measured in centuries rather than decades will be boring.
Again, we must consider other parallel changes. We are not talking about becoming what we now think of as a 90-year-old and staying in that condition for hundreds of years. These technologies will enable us to stay young indefinitely.
Moreover, we will have the opportunity greatly to expand our experiences, and even mental capabilities.
The future will be greatly enriched with the advent of such developments as full-immersion virtual reality and the expansion of our thinking ability. Life will be anything but boring. — Â