Sounds unlikely? It's not - it's actually quite likely.
The only way to get people to live for a thousand years or more is to develop advanced technologies that can manipulate our bodies down to the cellular and molecular level. So the question is whether humanity will develop the necessary technologies over the next 30 years, or not. Personally, I think it's very close to 100% certain that we'll manage to do this.
That is, we don't have to perfect the technology in 30 years. What we must do is to develop technology that can make old people 10, 20 or 30 years younger, biologically speaking, so an 80-year-old, for example, can get the body of a 60-year-old. In that case, he has bought himself 20 more years of life, and in those 20 years the technology will have progressed even further, so that when he is 100 years and his body again is like an 80-year-old's, he can rejuvenate more than 20 years. In all likelihood we will take treatments more often than once every 20 years, and if so, the remaining life expectancy can be illustrated like this:
The figure is not entirely accurate, partly because people aged 100 years and 0 years clearly don't have the same remaining life expectancy today, and also because the curves would be more jagged (since it might go some time between each treatment), but it still illustrates the point well: the numbers above the curves represent how old the person is today (today is all the way to the left in the figure), and if the curve hits the horizontal line at the bottom (the time axis), the person is dead. According to the figure, then, a person who's 80 years old today will have difficulty living forever, while a typical 50-year-old might just make it.
Normally, the remaining life expectancy of a person goes down as time passes and the person gets older. When someone is 50 years old, for example, one thinks that they have a shorter remaining life expectancy than when the person was 30. In the figure that means that the curve always slopes downward towards 0 (the horizontal line) as time passes. But in the future, better technology will cause life expectancy to start increasing: The older we get, the longer we can actually expect to live. In the figure this is illustrated by the curve turning and starting to slope upwards.
It would therefore theoretically be possible to live indefinitely without getting an old body, but not only is it possible for many of us, it is possible even if the technology isn't progressing particularly fast. For it is, like I said, not necessary for the technology that can make us younger to be perfect in 30 years, it only needs to work well enough that we can live long enough to benefit from the technology that will be developed after that. Looking at it like this, it doesn't really take all that much to get people to live for more than 1,000 years.
Many might still be skeptical of the notion that technology will progress fast enough over the next 30 years. Will we be able to rejuvenate people by about 20 years, biologically speaking, in such a relatively short time span? I am almost certain that the answer to that question is Yes.
Because technology will advance fast - very fast.
With a few assumptions, such as the Earth not being hit by a large asteroid, some aspects of the future can actually be predicted with a high degree of certainty. One of these is that we will have more efficient technology in the future than today. It's even become apparent that just how much better the technology will be is also quite easy to predict - in certain areas. The best known example of this is perhaps Moore's Law, which states that the number of transistors on an area doubles every two years. More generally, the amount of computing power we can buy for a fixed amount of money doubles in a relatively short span of time. 1) This was true long before we got transistors (Moore's Law), and it will probably also hold true after it is no longer possible to increase the number of transistors per area. At that point another technology with significantly greater potential will take over for transistors.
The time it takes to double computers' performance is only half the time it takes to double the number of transistors per area, for since the spacing between transistors is shorter, it also takes less time for signals to move between them. Thus, the performance of computers doubles, not every other year, but every single year!
The fact that the performance of computers does not increase linearly, but actually doubles at regular intervals, is very important. Those who know the history of the inventor of the game of chess know how few doublings are needed before we get to very large numbers: If we take the number 1 as the starting point, 10 doublings take us to about 1000, 20 doublings get us to a million and 30 doublings from the number 1 take us to a little over one billion. If the price performance of computers doubles every year, the price performance will thus be a billion times better in 30 years than it is today. At that point it's virtually just the imagination that limits what we can achieve with all that computing power.
If we examine how computing power per constant dollar has evolved since the year 1900, we will see that the time between each doubling is actually shorter now than it was 100 years ago. If this trend continues and we extrapolate the trend all the way to the end of this century, we might get a development that looks something like this: 2)
Note that the y-axis is logarithmic - each of the marked values on the y-axis is actually 100,000 times greater than the previous one. A straight line pointing upwards in a logarithmic plot corresponds to an exponential (explosive) increase. The amount of computing power we can buy for a given amount of money increases even faster than this!
Computers aren't just getting faster, they are also becoming smarter and can do more and more of the things we previously thought only humans could do. In 1997, the world's best chess player, Garry Kasparov was defeated in chess by a computer. In 2011, two of the world's best Jeopardy players were defeated in Jeopardy by Watson, a supercomputer developed by IBM. So with increased computing power and better algorithms computers have become smarter and smarter. The progress has been very rapid, and if it continues, machine intelligence will at some point not only be faster, but also become smarter than human/biological intelligence. Machine intelligence will then be able to make improvements to itself without input from humans. Ray Kurzweil, whom Bill Gates has called the best person I know at predicting the future of artificial intelligence, and who works as director of engineering at Google, is perhaps the best-known futurologist, and he has said that this will happen by the year 2045. 2045 is less than 30 years away.
Sure, computers are getting better, but how's that relevant for making people younger?
We take advantage of computers in ever more areas of our lives. According to Ray Kurzweil, as soon as something becomes an information technology, it starts progressing according to Moore's Law. The technology thus begins to progress exponentially, with regular doublings in performance. An information technology is a technology that uses computers extensively. In recent decades, biology and medicine has to an increasing extent started to become an information technology. With computers we can now, among other things:
- Read human genes.
- Edit genes with CRISPR/Cas9, a revolutionary technology that has been adopted by laboratories worldwide. Still better technologies for gene editing are under development.
- 3D print some human organs.
- Create a physical chromosome designed on a computer. Researchers at the J. Craig Venter Institute did this in 2010, before putting the chromosome into a cell where it caused the cell to start dividing.
- Diagnose diseases better than human doctors, based on image files, description of symptoms and information about the patient. (The Watson supercomputer has, among other things, been used for this purpose after its Jeopardy victory.)
- Measure the body's health condition using small sensors. Do you remember that relatively small device the Star Trek doctors scanned their patients with to diagnose them? In Star Trek, they called it a Tricorder. The X Prize Foundation has an ongoing competition where the goal of the participating teams is to create a Tricorder-like device that can be used to diagnose a few diseases, 16 of them to begin with. The aim is to give people, even in poor parts of the world, easy access to their own health information. Patients must therefore be able to use the Tricorder to diagnose themselves with ease.
So medicine is about to become an information technology, and that's the main reason why we can expect medical technology to advance exponentially in the future.
The more advanced our technology becomes, the smaller sized computers we're able to make, and in the long term we can envisage mini computers the size of red blood cells. We can have billions of these in our blood, and they can act as an artificial immune system that continuously helps our natural immune system to fix things that have gone wrong. In the long term this may be the way we will be controlling the aging process, but fortunately it's not necessary with technology that advanced in order to repair aging damage 'well enough' in the short term.
Most aging researchers agree that there's only about seven fundamental reasons why we age. Aubrey de Grey, the best-known advocate for defeating aging and Chief Science Officer of SENS Research Foundation 3), a charitable organization working to fight aging, stated already more than ten years ago that even without revolutionary new technologies there was about a 50% chance that we would be able, within 25 years, to repair the seven types of aging damage well enough to increase people's life expectancy by 25-30 years.
For this to be achievable in just 25 years, the level of funding would have to be very good, according to the Grey. Thus far, the funding has been far from as good as one might hope for, but important progress has been made, nonetheless, and 2015 was a good year for aging research. Private firms are now trying to develop treatments for four (perhaps soon to be five) of the seven categories of aging damage. Simply removing old "zombie cells" (senescent cells - cells that have stopped dividing, but that aren't being recycled by the immune system) has led to a 25% increase in longevity in mice. Actually, two different companies are now working to develop treatments to remove this type of harmful cells in humans, Unity Biotechnology and Oisin Biotechnology. The more firms competing to develop treatments, the greater the likelihood that someone succeeds, so this is very promising!
So considering how far we've come already and how fast technology is improving and can be expected to improve in the future, I don't think there's any doubt that we'll have the aging process under control in less than 30 years. Maybe 30 years is too cautious an estimate, even. Ray Kurzweil has said that already by 2030, life expectancy will increase by one year per year, and I actually won't be very surprised if he's right. But everyone in the world won't get access to the technology as early as Kurzweil estimates, which is why nearly 30 years might still be closer to the truth for most people?
Is it inevitable that we'll be living much longer lives in the future?
Living a long time is closely linked to being healthy. As long as you have good health, you are not going to die of aging. No matter how skeptical some people are today to the idea of people living lives of more than 1,000 years, I think most of them will still choose good health if they can. No one wants to get cancer, dementia or heart problems. One would have to be pretty principled if one refuses to take the anti-aging treatments that in the future can provide us with much better health, when most other people around us are taking them. It is in everyone's interest to develop these treatments and to have good health. 4) Technology trends indicate that the treatments will arrive soon, and, yes, it is virtually inevitable!
And we're not going to extend human life expectancy to a mere 150 years. It may well be that new, still unknown, types of aging damage will be found to be important when people start approaching 150 years of age, but given the incredibly fast pace of technological progress, at the time when the first humans will be 150 years old, it's going to be easy to figure out how to repair these new types of aging damage. So if you've made it to 150, you're "over the hump" (a long time ago), and then there's simply no limit to how long you can live.
1) An important reason why technological progress is speeding up as rapidly as it is, is that we're developing more and more effective tools, and with more effective tools, we're in turn able to develop even more effective tool.
2) But isn't the pace of technological progress eventually going to slow down? Maybe, but Ray Kurzweil (who thinks people are going to improve themselves by "merging" with the technology we're developing) thinks it's going to be a very long time until that's going to happen. In his essay The Law of Accelerating Returns, he writes:
Can the pace of technological progress continue to speed up indefinitely? Is there not a point where humans are unable to think fast enough to keep up with it? With regard to unenhanced humans, clearly so. But what would a thousand scientists, each a thousand times more intelligent than human scientists today, and each operating a thousand times faster than contemporary humans (because the information processing in their primarily nonbiological brains is faster) accomplish? One year would be like a millennium. What would they come up with?
Well, for one thing, they would come up with technology to become even more intelligent (because their intelligence is no longer of fixed capacity). They would change their own thought processes to think even faster. When the scientists evolve to be a million times more intelligent and operate a million times faster, then an hour would result in a century of progress (in today's terms).
4) Many people might think that the Earth will be overpopulated if we stop dying. That's far from certain.