“Is there anyone in India who does not admire China?” the Chinese scholar Yi Jing asked in 691 AD. Yi Jing had just returned to China after 10 years of study in India at the university of Nandala. Although Yi Jing admired certain innovations in India, he returned home even more convinced o China’s superiority. There was one sector in particular in which China’s superiority was evident and important; Yi Jing’s field of specialisation, ayurveda, the science of prolonging life towards immortality.

Both India and China considered the capacity to extend human life – even if not made available to the mass of the population – a sign of a superpower. They recognised more than 1000 years ago that although a country may pride itself on economic and military power, without recognition of being advanced in science and above all without being able to potentially offer its people a longer and healthy life, no nation can consider itself superior ideologically. The battle for the minds of the people begins with the body.

The same applies today. The rivalry between India and China – both by now modern superpowers – over the prolonging of human life continues today, as shown by statistics. In the period after World War II, commencing respectively from the establishment of the communist regime in China in 1949 and the independence of India in 1947, China has maintained a clear advantage in the ancient contest. At the present time, the average lifespan in China is approximately 71 years, while in India it is approximately 65 years. These lifespans represent an enormous improvement over the last two generations and are superior to those of a rival like Russia but still well behind the average lifespans of the USA or the European Union. Wealth has also brought problems to these last two – for example in terms of health, obesity, but in the battle of ideologies, the USA and the European Union appear to the world as the two superpowers in which there is the best chance of living long and well. This is thanks to medicine, lifestyle and diet.

The United States Census Bureau has estimated that the average lifespan in the United States (currently approximately 80 years) will have reached about 85 years by 2050. The United Nations has carried its own conservative projections much further into the future and estimates that by the year 2300 life expectancy in developed countries will be between 100 and 106 years and will still be very slowly increasing. The United Nations expects that less-developed countries will still be behind at that point, but that the gap will have greatly closed.

Together with a nation’s prestige that traditionally comes from being able to offer its citizens a longer lifespan, this continual extension of human life will also create significant problems. A continually aging population that expects to live in retirement not for just 15 years, but for 20, 30 or 40 years with the related medical costs and resulting over-population will create enormous costs. The ongoing debates in various countries on the strategy of increasing the retirement age demonstrate the problems posed by these great demographic changes. The challenge of providing a long life with a decent standard of living will affect more and more countries in the future and the search for possible solutions will increasingly involve new technologies. Some scientists foresee a future world in which people will not only have a longer old age, but in which the body will be rejuvenated, thereby permitting a longer youth and a longer working and active life.

This faith is based on proposed technology for life extension, particularly the Strategies for Engineered Negligible Senescence (SENS) put forward by British scientists. The goals of SENS go far beyond merely slowing aging and extending the human lifespan; those effects have already been noticeable for decades as a result of improved diet, standard of living and medical treatment. SENS aims at preventing or reversing aging, thereby extending lifespan indefinitely and even outrunning death altogether.

SENS identifies seven causes of aging: cell loss; cell aging; cancerous cellular mutations; mitochondrial cellular mutations (which affect energy production); intracellular waste products (such as those that cause atherosclerosis); extracellular waste products (such as those that cause Alzheimer’s Disease); and the weakening of extracellular links. The general approach of SENS is to develop new enzymes and drugs to stimulate or enhance the action of the immune system and other metabolic functions; to utilise stem cell therapy to create new cells; or even to use surgical intervention in some cases. SENS would also require great advances in nanotechnology – machines or robots so tiny that they can act at molecular level. The remedies would be applied periodically to try and return cells to a younger condition.

None of the proposed techniques of SENS are currently possible. Many scientists think they never will be and SENS has therefore been criticised as unscientific. Still, it is attracting significant investment from organisations and from rich individuals such as Bill Liao, the Australian founder of the internet networking site Xing. Supporters of SENS hope that investment and research will increase to such an extent that anti-aging technology eventually exceeds the actuarial “escape velocity”. This would occur when the speed of increase of life expectancy exceeds the speed of aging. Currently, average life expectancy is increasing by a matter of weeks each year. If technology allowed life expectancy to increase by more than 12 months a year, it would be theoretically possible to extend lifespan indefinitely. By using the latest technology to extend their lives far enough into the future to be able to take advantage of the next level of technology – and so on – humans could potentially live for centuries.

The most optimistic SENS scientists estimate that there is a good chance of the necessary technology to allow significant life extension being available within the next generation. If that were true, then beginning the “escape velocity” race against death is a real possibility for many people living today. There remains the problem of staying alive long enough to benefit from the new technology. For now, the only available strategies are the simple ones of diet, healthy lifestyle and exercise. These, combined with improved medicine have already greatly increased the average lifespan and will probably continue to do so.

Other branches of medical technology currently more developed than SENS are likely to be very important in the quest for life extension. The United States military is already experimenting with cloning techniques to create living replacement limbs for wounded soldiers. Cloning and body part replacement could also work together with SENS and other technology to overcome the most serious limitation on life extension potential. A person who is “immune” to old age and disease could still die from accident, violence or other trauma. The creation of stronger and more resistant limbs and organs might help such a person get nearer to immortality. For now, science has suggested other ways of buying enough time until new life extension technology becomes available.

One of these already being used is cryonics, commonly known as “freezing”. Many people have been preserved by cryonics immediately after death in the hope of being revived in the future when medicine, including life extension techniques, might be greatly advanced. It might even be possible in the future to use cryonics for limited periods of a few years to gain time to take advantage of new phases of technology. Ice damages body tissue, so modern cryonics uses anti-freeze substances to prevent ice formation. Even if any tissue damage did occur, cryonics users hope that future technology will also be able to repair that.

Cryonics has not so far been proven to work in the case of large mammals. A similar technique that has already been successfully tested for a few hours at a time on pigs, dogs and mice is suspended animation. Body temperature is greatly lowered and the blood is replaced by an ice-cold liquid. For resuscitation, the blood is returned and an electric shock given to the heart. Whereas cryonics is normally used after death, suspended animation is used on a living subject. Breathing and heartbeat may still occur, but extremely slowly, and theoretically the speed of aging is greatly slowed down. Both cryonics and suspended animation may eventually play a part in deep space exploration, as passengers could be revived after many years of travel. Science fiction has considered this possibility for years already.

There are – and there always will be – fears concerning the continuation of the arms race in space. However, the prolonging of human life raises many other ethical questions. Protests against cloning and other scientific processes are very common. The objective of extending human life towards immortality has been strongly criticised by the Christian church and by philosophers such as Francis Fukuyama and Jurgen Habermas. These criticisms arise in general from the concern that by overcoming death in this way the human being would in effect become a different entity and that a social order not based on the periodic substitution of people through death would be a nightmare.

However, even those who accept the general objective of prolonging life are often concerned for other reasons. These include the possibility that only extremely rich people could use the technology given the very high cost. This might increase economic inequality; the rich would live even longer and therefore accumulate even more wealth. It is also feared that totalitarian regimes would use the technology to reproduce themselves indefinitely. Some supporters of life extension accept that it would be essential to offer the benefits of the technology to everyone. It would be difficult to guarantee this, though, if rich people, companies and governments were prepared to pay any price asked in any part of the world. The same applies to other objections to life extension; the related world market might become so powerful as to be able to overcome any opposition.

Space exploration is one of the possible wider benefits that might come from research into life extension. The development of medicine – such as a cure for cancer – is another. Supporters of life extension also point to purely financial benefits that justify increased investment in SENS and related technologies. Age-related diseases such as Alzheimer’s affect thousands of people and cost billions of dollars each year. Part of that enormous human and monetary cost could be removed in future if life extension research discovered ways of preventing or curing these diseases.

It is likely that investment in ageing research will dramatically increase – and not only because the investors hope to have their own lives lengthened. Companies and other institutions offering life extension may become very popular and profitable and therefore could represent attractive investment opportunities. Larry Ellison, the founder of Oracle software, has been investing heavily in the sector for ten years. The current financial crisis shows that traditional investments like real estate and shares are not always safe and investors with a lot of money to spend might look increasingly to future growth areas. Life extension could be one of those as more people start to believe in it and to spend accordingly.

Life extension raises many difficult ethical issues. One of these is whether only rich people will be able to make use of it, due to the huge cost. This could lead to inequalities of wealth increasing, as rich people lived longer and accumulated still further wealth. It is also feared that totalitarian regimes could use the technology to perpetuate themselves. Some supporters of life extension agree that it would be essential to allow everyone to benefit equally. This is likely to be difficult to control, however, if rich individuals, companies and governments were able to pay whatever price was asked anywhere around the world.

Still, Yi Jing would today be pleased to see China still ahead of India in the ace for immortality. And he would probably be even happier to think that the ancient challenge of seeking immortality might take his countrymen much, much further away from the university of Nandala – even as far as the stars.