Transumanar

THE STRULBRUG FALLACY: AN ESSAY BY EXTROPIA DaSILVA

This very good essay by Extropia DaSilva shows how to counter some of the usual “arguments” against life extension. Published with permission.

THE STRULBRUG FALLACY: AN ESSAY BY EXTROPIA DaSILVA

When surveys are conducted asking if people would like to live beyond the ‘natural limit’ of 120 years old, the answer is usually ‘no’. When asked to explain the reason behind their answer, replies tend to be along the lines of ‘too much life would be boring’ and ‘how would the Earth support us all’? What I want to show is that all such arguments stem from various misunderstandings and are therefore hopelessly weak.

Take the argument that life would become boring if it went on for too long. There may be a grain of truth in this statement, but I simply cannot believe that 120 years is sufficient time in which to have ‘been there , seen it, done it, know it all’. In fact, I think even a lifespan of 1000 years would not be long enough to have exhausted all opportunities for education and entertainment. Yet so many people truly believe life would be boring if it were not much longer than 10 decades.

Why is this? I think it is because they have fallen foul of what I call the ‘Struldbrug Fallacy’. It is named after a race of people in Swift’s ‘Gulliver’s Travels’ who are immortal. They can never die, but the cruel catch is that they age just as normal people do. The eponymous traveller’s initial marvelling at the gift of immortality (no end to the opportunity to improve oneself) turns very bleak as he considers how frail a 90 year old is compared to a person in the full bloom of youth, and therefore how much frailer a 190 year old must be.

The Struldbrug Fallacy is to ponder the prospect of extreme life extension in the following way: ‘Beyond a certain age, the older you get, the frailer you tend to be. No 90 year-old is anywhere near as fit and healthy as they were in their youthful days. If I were much older than that, I would surely be even more frail and even less able to enjoy life. What would be the point in living beyond 100?’. But such reasoning completely misunderstands the way in which extreme life extension will be brought about. The intention is NOT merely to add more years to our current life cycle. Rather, the goal is to SLOW DOWN the aging process to the point where negligible senescence is achieved. Senescence refers to the progressive loss of physical robustness that happens as we age and so negligible senescence means very little to no increase in physical and mental frailty as time goes by. It is important to understand that this in no way prevents death from accident or malice. It is just that, no matter how many birthdays have passed, you are no more likely to die than you were at any earlier point in your life. Some ethicists like Leon Kass have argued that ‘immortality’ would rob us of the opportunity to lay down our life in some heroic act, but that clearly mistakes ‘indefinite’ life for ‘immortal’ life. A fit and healthy 200 year old firefighter would have been in as much danger, and every bit as heroic, if such a person had been caught up in the Twin Towers attack.

Once you grasp the true goal of life extension, you can see how the question ‘would you like to live to be 100?’ aught to be rephrased to something like ‘would you want to be prevented from dying this year’?. I would hope that most fit and healthy people would reply in the positive and have no end of good reasons to want to see another 12 months go by. And if you asked them again, many, many decades in the future, way past their 100th birthday and yet just as fit, surely they would be just as reluctant to see life terminated at the end of that year, no excuses?

Another reason for not wishing life were a great deal longer is that it seems like a fool’s hope. We know, from the fact that every person ever born has grown old and died, that avoiding a similar future is not an option. Increasing senescence leading to a non-negotiable expirary date is the inevitable fate awaiting us all. But this kind of reasoning has been used before. In 1839, Dr Alfred Velpeau stated: ’The abolishment of pain in surgery is a chimera. It is absurd to go on seeking it today’. It must have seemed perfectly logical that cutting a person open with a knife could not help but cause them pain. Pain is also a phenomenon that is easy to explain in terms of evolutionary benefit- it is ’natural’ that injury should result in such strong signals. But regardless of the fact that cutting someone with a knife hurts and regardless of the fact that there is good reasons why this should be so, you can probably see that the good dr was quite wrong to argue that ’knife’ and ’pain’ were inseperable. The discovery, in 1846, of ether anesthesia, put paid to that.

The lesson we learn from this example is that advances in knowledge and technology can sometimes alter our perception of what is ’inevitable’. Admittedly, we still lack a convenient means to disable the various underlying principles of increasing senescence, but we ARE gaining clearer understandings of exactly why our bodies grow frail with time. And, more importantly, strategies have been outlined to counter each and every one discovered so far. There really does seem to be nothing behind the aging process that could not be fixed, given suitably advanced bio and nanotechnology. You do tend to get opposing voices condemning such pursuits as ’defying nature’ but that just goes to show that the goal of negligible senescence is indeed not impossible. If it were, why fret about its eventual success? By the way, arguing against extreme life extension on the grounds that it defies nature almost certainly places its advocate in the unfortunate position of being an utter hypocrit. We defy nature when we cure disease, when we wear glasses to correct poor vision, when we turn up the heating on a cold winter’s day, when we perform open-heart surgery on a patient with their capacity to feel pain temporarily turned off. You could write a very long list of all the ways in which our species has used technology to ’defy’ nature and it is inevitable that even the most staunch believer in the ’unnaturalness’ of indefinite lifespans has used some of them.

But perhaps the warning against defiance of nature probably has more to do with the supposed environmental consequences of extreme life extension. These are the ’where would we all live, earth has finite resources’ style of arguments, or the objection that it is immoral to hang around, spending the kids inheritance. I think that this objection is no less weak and flawed than the others. Our species’ tendency to put short-term profit before long-term environmental consequence is due to the fact that, so far, we have tended to die before the price for our partying had to be paid. When climate scientists warn that we will find life very difficult in the year 2100 unless we change our ways, most people old enough to understand the basics ’know’ they will be dead by then. A consequence that comes into effect AFTER you die might as well be one that never happens at all. It is somebody else’s problem. And those people not old enough to understand the science are by definition not in a position to do anything about it.

Look, I don’t know for sure that if humans had lifespans measured in centuries rather than decades we would be less inclined to be apathetic towards drastic consequences hundreds of years in the future, but it does seem like a reasonable conclusion. On the other hand, dying only a few decades after our minds mature is a tragic waste of resources. Each person carries in their head a vast database of knowledge, all of which is lost when they die (save for what portion of it they recorded for prosperity). Terry Grossman asked us to imagine that one person’s life experience equalled one book. That being the case, ’every year, natural death robs us of 52 million books, worldwide’. You can appreciate what a waste of knowledge that is by understanding that the US Library of Congress holds 18 million volumes. Therefore, it is like burning the world’s largest collection of books to the ground, three times over.

You could plausibly argue that the reality is less or more tragic. I think it is safe to assume that the sum total of one person’s life experience would fill many books, as opposed to one. Therefore we are robbed of an even greater body of work every year. On the other hand, I know my own head is filled with trivial information that is not much use to anyone. Perhaps only a tiny percentage of what the average person knows is worth recording for prosperity. Nevertheless, it seems to me that science should place a high priority on preventing increasing senescence in the generations old enough to understand and deal with the issues we face. And there should be a very LOW priority placed on developing fertility treatments to swell the ranks of the generation too young to help. People who think the best way to secure our future is to have children and die ’on time’ are saying: ’Let’s continue to wipe out a generation’s worth of knowledge, and wait while the ignorant generation slowly matures to the point where they can understand the problem, and then wait yet more years while they work out a solution’. But what happens if that generation takes a lifetime to solve these issues? They then have a ’duty’ to die..wave goodbye to another 52 million ’books’.

The issue of fertility does raise a seemingly valid objection. Nobody wants to die so long as life is worth living. Nearly everybody would like to become a parent. As the Earth really does have finite resources it seems we cannot have our cake and eat it. That objection is commonly raised in discussions about living indefinitely: ’how would the planet support us all’? This kind of argument fails to take into consideration the full impact of the knowledge and technologies required to achieve negligible senescence. It would require exquisite control over matter at the molecular level, and technology like that would be capable of managing the world’s resources far more efficiently than today’s industries. For transhumanists, the Holy Grail of medicine is the development of nanoscale machines capable of repairing the body from the level of molecules upwards. The existence proof for such molecular manufacturing comes from nature itself- all life is built using bionanotechnology and nature’s ’machinery’ has run for 4.3 billion years without ’killing the planet’, whatever that means. A naïve view would lead one to believe that widespread use of molecular nanotechnology would provide an industrial infrastructure every bit as ’green’ as nature. I say ’naïve’ because the nanotechnology that nature uses is far from optimal. Ray Kurzweil commented, ’biological systems are limited to building systems from protein, which has profound limitations in strength and speed’. In fact, for all its undeniable beauty, all the products of natural selection fall far short of what is theoretically possible.

If the layperson is aware of one product of nanotechnology outcompeting nature, you can bet it is the dreaded ’gray goo’. A lot of people really do believe that such an outbreak is bound to happen if we pursue nanotechnology, either by accident or sheer malice. I have already written an essay detailing why this is not necessarily so (’snowcrashing into the diamond age’) so here I will point out a fact that most people ignore: There already is a gray goo plague consuming the world’s resources. Our current technology allows us to support a worldwide population far beyond anything Thomas Malthus would have thought possible, but it is becoming increasingly obvious that sustaining modern civillization demands far more resources than the Earth has to offer. ‘Ah’, comes the inevitable response, ‘we can seek new planets to colonise‘. this is often held up as being some grand vision of our future, but I beg to differ. It seems to me that this notion of endlessly-replicating humans consuming the resources of one planet and then spreading out to do likewise to other worlds is a picture of the human race as a galactic viral infestation.

It would be much better if we learned to use the resources of THIS planet as efficiently as possible and it doesn’t get much more efficient than manufacturing everything we need at the level molecular nanotechnology would allow. You might wonder, though, if nanotechnology will support the human race once we develop nanomedicine. It has been estimated by nanomedicine researcher Rob Frietas that preventing 99% of naturally occurring medical problems would enable us to live for more than a thousand years. Assuming ‘medical problems’ includes infertility, it might be the case that nanomedicine results in humans becoming animals that never fail to bring a pregnancy to term and can expect to live for a millienium. One would think that even Drexlerian nanotechnology would be insufficient to sustain a species like that.

It seems, then, that there is a valid objection. The medical knowledge required to halt the aging process could also be used to eradicate infertility. Indeed, given the natural urge to procreate and the anguish felt by couples unable to start families, the case for eradicating fertility could be argued rather strongly. However, to argue that the technologies required for engineered negligible senescence could also be used to treat infertility, and that this would inevitably lead to explosive population growth, is to put the transhumanists’ desire for indefinite lifespans in the wrong context. People tend to treat radical life extension as the goal, rather than one more necessary step towards a richer future. You might call this ’poverty of imagination’, the tendency to miss the bigger picture while focusing on minor details.

In version 3.11 of ’The Principles of Extropy’, Max More wrote ’Extropy means seeking more intelligence, wisdom, and effectiveness…perpetually overcoming constraints on our progress and possibilities as individuals, as organizations, and as a species’. Extropians accept that the laws of physics may impose certain constraints, but even here there is a necessity to continually question our faith in the reliability of our understanding of physics and hence our assumptions of the limitations those laws impose. As soon as science finds a way through any barrier, extropians consider it an imperative to develop whatever practical means there are to achieve this.

So engineering negligible human senescence should be seen, not so much as a goal, but a by-product of a greater drive toward expanding our opportunities to learn more, enjoy more, continue to strive towards finer levels of self-development. But so what? What does this have to do with perceived explosions in population growth? Well, there is extensive evidence proving a high correlation between female literacy and fertility rate. James Martin, one of the world’s most respected authorities on the impact of technology on society, wrote in ’The Meaning of the 21st Century’ ’In the 1980s in many of the world’s poorest countries, only 3% of the women could read, and the average number of children a woman had was seven, sometimes eight…as female literacy spreads, fertility rates drop…when almost all women can read, the average number of children a woman has is often below two…A chart of literacy rate against fertility rate…doesn’t have smooth mathematical curves, but its message is unmistakable. Teaching women to read…slows the population growth.’

Of course, lessons in effective birth control are essential too. But why should literacy have this impact on fertility rate? If I were to hazard a guess, I would say that since literacy is an important step towards being educated, and being educated leads to better career prospects and higher aspirations, these women come to feel they have more to contribute than just raising children. Certainly, that is the case with women in first world societies. The great advances expected in genetics, robotics, information technology and nanotechnology will converge and combine to open up vast new markets, which will in turn will open up a wealth of opportunities in terms of career prospects and lifestyle choices. Moreover, these technologies may very well put an end to the need to divide our lives up into distinct chapters, since this is by and large dictated by the tick of our biological clock. ’This part of a person’s life is spent in basic education, that part in higher education. After that comes career/kids and don’t forget to save for a comfortable old age’. People continue to assume that this course of events will play out, not only for their life, but the life of their kids and grandchildren. But already we are seeing the power of science and technology to disrupt the status quo. We see people long past ’natural’ child-bearing age nevertheless giving birth and the sight of a 70 year old cradling her newborn babe is but a taste of things to come. In the future, very young children whose brains are wired directly to computer networks running formidably powerful forms of artificial intelligences may be fundamentally smarter than even the most gifted of today’s adults. Such bright eight year olds would have no trouble completing one of today’s courses in higher education. And what about the adults? TODAY there is a very good reason why the thought of old-aged people becoming parents receives the negative reaction that it does. It is because these people can be expected to die before they have raised their child to adulthood. Like it or not, there is a window of opportunity in which it is biologically most acceptable to have offspring. But people long past their 70th birthday who are nonetheless as physically robust as they were aged twenty could decide to have children and it would be difficult to see why this would raise the objections it does today. Similarly, a person as ’old’ as that who still feels a need to put off having children in order to enjoy their own life could hardly be said to be risking the window of opportunity closing in their face: Thanks to engineered negligible senescence, it wouldn’t ever close.

Well, it might. Negligible senescence only makes you equally likely to die from accident or misfortune as a person in the full bloom of their youth, it is by no means ’immortality’. Lives may still be lost to natural or human-created disasters and so our continued existence on this planet may well necessitate the creation of new lives. So long as the birthrates were not higher than the average amount of lives lost each year, this would obviously result in sustainable population growth. But can we really be certain that the vastly wider set of life experiences available to transhuman societies really would ensure enough people delay becoming parents to keep the population levels from rising too high? One might think that such a high-tech society would be far less accident prone than ours, and with lives measured in centuries enough people would need to postpone parenthood for a very long time. Surely, it must still be the case that the earth’s ability to support a technologically-advanced civillization would be pushed beyond all reasonable limits?

But if you think this is the case, you are seriously underestimating the planet’s capacity to support intelligence. Intelligence is a form of information processing and it is an oft-noted fact that, through our technology, we have continually discovered ever-more efficient forms of computation. In 1965, intel founder Gordon Moore predicted, ’by 1975, economics may dictate squeezing as many as 65,000 components on a single sillicon chip‘. He believed this would be the case because, since the first chip had been invented, the amount of transistors that could be packed onto a chip had doubled every year. This regular cycle was later adjusted to a doubling of processor power every 18 months. Carver Mead called this prediction ’Moore’s Law’.

1975 passed a long time ago but Moore’s Law is still going strong. In 1978, intel’s chips performed 6000 calculations per second (CPS). By 1989, cps was 1,200,000. By 1999 it was 9,500,000. In 2007, intel announced a protoype multiccore chip that could deliver more than 1 trillion mathematical calculations per second. To put this into persepective, compare that chip to the first computer to benchmark at a teraflops. ASCI Red required 10,000 Pentium pro processors and took up about 2,000 square feet. Intel’s experimental chip is about the size of a large postage stamp and it consumes 62 watts. ASCI Red needed 1,000 times more power.

The weird thing about Moore’s Law is that, somewhat like Jonathon Swift, rumours of its demise keep cropping up and always turn out to have been exaggerated. Obstacles are seen looming on the horizon, prompting insiders to announce that Moore’s Law will not continue, but nevertheless it does. Still, nobody would be foolish enough to predict that intergrated circuits will double their performance forever, because there really are fundamental limits that will ultimately prevent us squeezing more performance out of ICs. But the consensus of opinion among computer scientists is that the demise of Moore’s Law will not mean an end to the doubling of computing power. They believe this is so because the regular doubling was not a phenomenon that began with sillicon chips. In actual fact, as Ray Kurzweil has noted, this growth in computing power runs smoothly back through 5 paradigms of information technology. Singularity theorist John Smart, moreover, has noted that “Computation” (which he defines as ’forming an encoded internal representation of the laws or information of the actual environment’) has discovered ever-more-clever ways of using matter, energy, space and time to process information, and that this has been happening long before humans came on the scene. In his own words: ’our planet’s history of accelerating creation of pre-biological (atomic and molecular based), then genetic (dna and cell-based), neurologic (neuron-based), and memetic (mental pattern-based)…information arises out of, and controls, the continuous reorganization of matter-energy systems.’

So any one technology will inevitably run up against limits. But a more generalised capability like computation, storage, or bandwidth tends to follow a pure exponential, bridging across a variety of technologies.

Actually, the laws of physics place ultimate limits on the growth of computing, but before we get around to discussing them, we need to look at another good reason why the growth of computing power won’t end with the IC. It is because there exists another information processor that puts contemporary computers to shame. The human brain is 100 million times more efficient in power/ calculation than the best processor, and it stands as existence-proof of the levels of computation that can be reached. It also points us towards the 6th paradigm of computing systems, which is three-dimensional molecular computing. Current ICs cannot be stacked in a 3D volume because so much heat would be generated that the sillicon would melt. Carbon nanotubes, widely held to be crucial components of 6th paradigm computing, are incredibly heat-resistant and can therefore be used to construct cubes of computing circuitry, in contrast to today’s chips. Another advantage with using molecules to store memory bits and to act as logic gates is that molecules are so very tiny. ’Moore’s Law’ is fundamentally driven by miniaturization. Semiconductor feature sizes shrink by half every 5.4 years in each dimension, and this means that the number of elements per square millimetre doubles every 2.7 years. Current logic gates are only 50 nanometres wide and chips pack in billions of components. But, incredibly, a single drop of water contains roughly 100 times more molecules than all the transistors that have ever been built.

Molecular electronics is not just theoretical. A company called Zeta Core has built molecular memories using multiporphyrin nanostructures. The key to using these molecules as a storage medium lies in the fact they can be oxidised and reduced (electrons removed or replaced). Multiporphyrins have already demonstrated up to 8 digital states per molecule. Other nanotechnologists have proposed encoding information in fluorinated polythene molecules, where each bit is marked by the presence of fluorine or hydrogen on a certain carbon atom. Such a system would use 10 atoms per bit, which would correspond to 5.10^21 bits if diamondoid densities were reached. Analyses of existing nanotube circuits point to a one-inch cube of such circuitry performing 10^24 CPS. Estimates for the brain’s computational capacity range from 10^14 cps to 10^19 cps. Assuming the highest estimate is true, 10^24 CPS is equal to one hundred thousand human brains. One hundred thousand, packed into a device not much larger than a sugar cube. You can start to see how the resources the earth can provide for intelligence might, in fact, go a very long way.

Two questions that might be asked are: ’How do we calculate the computational capacity of the human brain’ and ’aren’t brains different to computers’? The second question is really an objection to AI and it is one that does not take into account neuromorphic modelling, which involves using technologies to analyse how a brain region works and using this knowledge to develop software running functionally-equivililent algorithms. The pace of building working models is only slightly behind the availability of brain scanning and neuron-structure information. We can take a region we have already reverse-engineered, take our knowledge of its capacity and extrapolate that capacity to the entire brain by considering what portion of the brain that region represents. Various estimates of different regions all result in similar orders of magnitude for the entire brain- somewhere between 10^14 and 10^15cps. The highest estimate (10^19cps) assumes that we must simulate every nonlinearity in every neural component, but it is generally believed that this level of detail is unnecessary unless you are uploading a person (we’ll get to that later).

The common objection to AI (’but we don’t know how the brain creates intelligence’) assumes our current level of understanding will never improve. This is clearly ridiculous. In contemporary neuroscience, models are being developed from diverse sources that include brain scans, interneural connection models, neuronal models and psychophysical testing. Thanks to increasingly sophisticated search engines, the 50 thousand neuroscientists worldwide can easily find, share, and add to this growing body of knowledge. And they are being helped by the scientists and engineers who are building ever-more accurate brain-scanning technologies. Nanotechnology expert Rob Frietas has exhaustively analysed the feasibility of using micron-scale robots to scan a living brain cell by cell, molecule by molecule, thereby allowing us to copy the neural patterns of the brain into another medium without necessarily understanding their higher-level organization. The objection that you have to understand exactly how something works before you can copy it is demonstratably false. Compilers translate computer programs from one language to another without understanding how they work. Photocopiers faithfully copy books even though they cannot read. Nanotechnology will ultimately enable us to both match (indeed, surpass) the computational power of the brain and to build neuromorphic models that reproduce its capabilities.

You might be thinking that I have gone off on a wild tangent. Rather than talking about indefinite lifespans and finite living space, I am talking about AI. But the drive to reverse-engineer our internal organs will have many medical benefits. For instance, UC San Diego’s Andrew McCulloh said, ’we can do a good job now of modelling on a computer what happens to cardiac cells in a heart failure, and predict how a heart contraction will respond to a drug’. As organ simulation software matures, drug trials will be simulated and yield results in hours, rather than months as is the case now. Another benefit is that neuromorphic models of brain regions could be installed in living brains when the biological region fails. We have already starting doing this with cochlear and retinal implants, with an artificial hippocampus just about ready for animal testing.

Nanobots will eventually be able to repair our bodies at the molecular level, thereby effectively halting the aging process. But why be satisfied with simply maintaining a body that is essentially a large bag of seawater? It would be far better to inhabit the morphable bodies and explore the enormous possibilities of virtual reality, if only we had a way of transferring our very consciousness into cyberspace. Anders Sandberg explained that there are many advantages to life as a software (rather than a biological) being. ’Less resources are needed to sustain the being, evolution of intelligent beings directed by them instead of natural selection becomes much more realisable, and the limits to its existence are determined by the computing system it exists in, rather than a constant body’. A very radical transhumanist proposal-uploading- involves scanning a brain at such a fine-grained level that everything stored on it, all the memories, personality traits, etc, of its owner are faithfully transferred to a model of that brain running on a suitable computing platform. As you may well imagine, whether this could ever work in practice, and if a copy of a mind can be said to be the same as the original person, are both controversial points. I have covered all this already in ’Post-human Perspectives Of Self part II’. Here I will assume uploading is a viable future technology and explain how, even given the limits of information processing and storage, we will be able to support numbers of uploaded humans that beggar the unnaugmented imagination.

The amount of computation that can be performed is ultimately limited by the amount of information that can be stored in an isolated region of space with a finite energy content, and by access to available materials. The former tells us that there is a finite size that the miniaturisation of computing elements can reach, thereby placing an upper limit on the computational and memory densities of a system. As we progress from ’micro’ to ’nano’computing, it is perhaps tempting to suppose we will then progress towards ’pico’, ’femto’ and so on through infinitesimally small scales. But since the region and its energy content are bounded, the phase space of the system must be bounded as well. Quantum uncertainty ultimately prevents phase space from being divided too small, because you cannot encode information if the partitions are so fine they are impossible to distinguish.

So the amount of bits that can be stored on a hydrogen atom are ultimately limited…to one million bits. The so-called Bekenstein bound tells us that the particles comprising one average human have the potential to store 10^45 bits. Now, if 10^15 bits are sufficient to encode one human-brain equivilent, and assuming a thousand times as much storage would be required for the body and its surrounding environment, the person’s living space would consume 10^18 bits. As for the world and its entire population, that could be encoded in 10^28 bits. That is, of course, a very large amount of bits, since it literally describes a world of information. But the optimised storage capacity of the particles in one human- 10^45 bits- is astronomically larger. It is equivilent to the biospheres of a thousand galaxies. I will say that again, just to make sure it sinks in: Encoded as properly efficient cyberspace, the bits represented by one human being would provide enough computation to support a population of uploaded people equal to 10 billion people for every star in a thousand galaxies! One person!

It boggles the mind, but we need to be cautious when dealing with capabilities pushed to the very limits permitted by physical laws. The technical capability required to achieve these limits would be prodigious. In order to reach the ultimate density of one million bits per hydrogen atom, it is necessary to first convert all of its mass into energy. That is essentially what happens in a thermonuclear explosion, and Ray Kurzweil noted that ‘we don’t want (an explosion) so this will require some careful packaging’. Moreover, completely converting an atom’s mass into low-energy photons (each of which stores one bit) requires matter/antimatter combination and anihilation, or even the transformations of matter and energy that occur in the extreme environments of black holes. One might well question technology’s ability to scale to these levels.

Never mind, though, because the computational potential of ordinary matter is very high indeed. Kurzweil noted that a 2.2 pound rock weighs about the same as a brain but when it comes to computation, one far outperforms the other. You would be forgiven for thinking the brain must be the winner here, but that is a prejudice brought about by an inability to easily see the activity happening at the atomic level. Here we find electrons being shared back and forth, particles changing spin and rapidly moving electromagnetic fields. The latter alone represents one million, trillion, trillion, trillion calculations per second.

However, the belief that a brain is a better computer than a rock is justified by something called ’computational efficiency’. In other words, the fractions of matter and energy taking place in an object that represent USEFUL computing. That’s where the stone loses out; the structure of the atoms is effectively random and no good for performing useful work. A brain is slightly more organised to perform useful computing, but is still far from its potential of 10^42 cps. A 2.2 pound object, properly organised, would have a capacity equal to ten trillion planets, each with a population of 10 billion people.

On a logarithmic scale, our brain lies roughly halfway between a rock and the ultimate ’cold’ computer (cold in that its mass has not been entirely converted to energy). It also turns out that, on a logarithmic scale, the average size of a human being places us roughly halfway between the subatomic and the astronomical. That we have evolved enough complexity to understand what the limits of computation are, and also the technological ability to reach them, are both consequences of our position on the logarithmic scale. Thanks to our size, we are strong enough to break molecular bonds in solid materials, bend and fashion metals, etch and sharpen hard materials like flint. The kinetic energy a human can obtain from throwing a rock is sufficient to kill other animals. These capabilities obviously enabled our technology to grow, something that could not happen if we were much smaller. Evolution favours different reproductive strategies for large and small animals. Large animals tend to have few young and devote great care and attention to their wellbeing. A lower probability for survival is not counterbalanced by a large number of young (as is the case with small animals who tend to have large litters) and a large body represents a significant investment of scarce resources. Both make longer lifespans sensible from an evolutionary perspective, because longer lifespans make the investment in resources more worthwhile and enable the nurturing of young to reproductive age. Compared to most animals, human beings have extraordinarily long periods of childhood and a large size, a long lifespan and extended learning periods all facillitate technological evolution. As well as manipulate matter in a variety of ways, we can manipulate energy. Most importantly, we aquired the capacity to manage fire. Again, our size enabled this because as the volume of combustible material gets smaller, the surface becomes too small for the flame to persist and so it dies. As is the case with computing elements, there is a minimun size for a flame, which is defined by a balance between the volume of combustible material and the surface area over which oxygen can fuel the combustion reaction. This means very small animals cannot make use of fire because the smallest stable flame would be too large to be safely approached in order to feed it. But at our size, small and stable flames are well-suited to our needs and our capacity to manage fire aided our mental development. It provided light and it increased the range of palatable foodstuffs. The former provided us with more hours in the day to devote to activities, and the latter allowed more time to be devoted on activities other than hunting (because the greater variety of foods you can eat, the less time you need to spend looking for dinner). Learning became more extensive and the long periods of close interactions with community members lead to complex relationships in which extensive knowledge on how to manipulate the environment could be shared.

We progressed from storing knowledge in our minds and imparting it through language, to manipulating the environmental resources of matter, energy, space and time to perform both roles. In modern civilization, our accumulated wealth of knowledge exists in the cyberspace of the Internet. 600 billion pages. A massively decentralised ’computer’ with a total RAM of roughly 200 terabytes and 10 terabits of data coursing through it every second. No single neuron, no single brain component, is capable of reaching human-levels of intelligence but the ensemble clearly is. Similarly, while no individual computer has achieved the 20 petahertz threshold for intelligence, the ’computer’ and its distributed chip of billions of pcs has, and its growth has clear parallels with the way brains develop. I have explained all that in ’Metaverse Reloaded’ so here I will concentrate on the second limiting factor to computational power: available resources.

When I described our brain as sitting roughly halfway on a logarithmic scale between a rock and the ultimate computer, I was assuming an equivilent mass for all three. Of course, we hardly restrict information-processing to a mere 2.2 pounds of matter. Once we have the nanotechnological capability to stop aging, we shall also be able to provide all material needs extremely inexpensively, at least where physical wealth is concerned. For a nanotechnological society, value is almost entirely represented by information. It seems reasonable to assume, then, that the less capable matter is at storing information, the less valuable it will be. To borrow a phrase from Stross’s ’Accelerando’, ’if it isn’t thinking, it isn’t working’. Given that the potential computing power of 2.2 pounds of matter is 10^42 cps, the potential locked in the 6.10^24 kgs of the entire planet must be many orders of magnitude higher. But if we measure MIPS per millimetre , we find very little useful computation occurring. In terms of its ability to process our thoughts, most of the solar system is a dead loss and we would barely scratch the surface of its potential if humans migrated to and filled every body orbiting the Sun.

Still, the Internet represents outward growth of computing, and the number of chips is increasing at a rate of 8.3% per year. Natural selection arranged biological matter to perform crude computations, and we now use those abilities to increase the computational capacity of our resources. If we assume available energy is the total output of the Sun (roughly 10^26 W) and available matter is represented by everything orbiting it (roughly 10^26 kg) we begin to see the outlines of a future internet on a scale beyond the imagination: Litterally, a star-sized ’internet.’ The ‘current ‘net is a computing system comprised of a global network of Pcs. This future computing substrate will consist of enough information processors to ’englobe’ the Sun in a cloud of computing platforms. According to J. Robert Bradbury, each individual component requires a power collector, such as high-efficiency solar cells; computing components, which would ideally be nanoCPUs with high-bandwidth optical communications channels to similar devices; storage components, with the ideal being photonic storage which would allow the lowest possible amount of energy with which to store a bit, and radiation protection. Some of the material locked up in planets etc is not usable for energy production or computing. Resources like iron, helium or neon could be used to provide shielding against high-energy cosmic rays.

As well as designing and building such components, we must also develop an assembly process that can be scaled up to handle the mammoth task of reducing planets to streams of elements and then reassembling them into the needed parts. Bacteria demonstrate a way to provide sufficient numbers of assemblers in a short space of time, via exponential assembly. In only four days, a single bacteria produces enough replications to fill a sugar cube. Four more days, enough to fill a village pond, and four days later its offspring would fill the pacific ocean. Within two weeks, provided it does not run out of resources (which is, of course, what always happens) a single bacteria could have converted itself into a mass of bacteria equal in mass to an entire galaxy. This demonstration of the feasibility of molecular manufacturing is often held up as a proof of principle for molecular nanotechnology. It should be pointed out, though, that nanotechnology is not required for any stage in Bradbury’s proposal. The exponential assembly, for instance, could be handled by the kind of automata John Von Nuemann described in 1965 which, along with Feynman’s speech ’There’s Plenty of Room At The Bottom’, laid down the groundwork for Drexler’s vision. But nanotechnology would be the optimal choice so I assume here that it will be in widespread use by the time a project of this magnitude is attempted.

According to Bradbury, the construction job begins with the conversion of one or more asteroids into solar power collectors. It will take several years to manufacture enough solar collectors to harvest the 10^23 watts required for the next stage: Building enough power collectors to harvest the Sun’s entire output. If we assume a power-to-mass harvesting capability of 10^5 W/kg, the sun’s 4.10^26 watts implies a mass requirement of 10^21 kg for solar collectors in Earth orbit, with the mass requirement reducing if we build closer to the star (for obvious reasons we cannot build too near to the sun). There is enough useful material locked up in the asteroid belt to provide the required solar collectors. More likely, though, is that the 10^23 watts from stage one will be beamed to Mercury and the bulk of that planet used to provide sufficient power collectors to harvest the total output of the Sun. That energy is then used to run the process of disassembling all but the giant gas planets, which will require extra energy in order to lift matter out of their gravitational well. Assuming exponential replication of nano assemblers, dissaembling the minor planets will take weeks to months. Von Nuemann-style self-replicating factories would require years or decades to complete the task. The raw materials are then reprocessed into ’computronium’ or matter/ energy organised to perform computations as efficiently as possible. Bradbury assumes this will be rod-logic nanocomputers capable of operating in conditions hot enough to melt iron. High-temperature rod logic nanocomputers could be made from diamond (melting point 1235 degrees K) aluminium oxide (MP 2345K) or titanium carbide (MP 3143 K). As well as the nanocomputer, each component consists of a solar array facing the sun to harvest useful energy, a radiator for disposal of waste energy, and the surface of the computer will incorporate communication arrays of light transmitters and receivers, composed of vertical-cavity-surface-emitting-lasers to provide high-bandwidth communications to adjacent devices.

As a consequence of the 2nd law of thermodynamics, the computers will produce heat that must be disposed of. But, rather than just radiating this waste energy into space, another even larger shell of nested computing elements could enclose the first one and do what work is possible with that energy, and another beyond that, and so on. If the inner shell runs close to the melting point of iron, the outer shells would be almost as cold as liquid helium. The radiation emitted by the outer shells would consist of low energy infrared photons which are extremely difficult to harvest for direct conversion into electricity. The outer layers are therefore likely to use mirrors to focus thermal energy and heat engines with Carnot cycles to gather power.

Russia is famous for its wooden dolls that can be opened to reveal a smaller doll nested inside, and one inside that..dolls all the way down. They are called ’Matrioska Dolls’. Here we have a shell of computronium containing another, and another, with a star sitting in the centre providing the energy for its thought processes (actually, ’cloud’ might be a better description than ’shell’ since the orbiting computing platforms will not be a solid sphere). Bradbury named his theoretical mega scale computer the ’Matrioska Brain’. How powerful a computer is it?

If no nanotechnology were used, and we instead relied on most of the sillicon in Venus as raw material and current trends in sillicon wafer production, the MB would have a thought capacity a million times greater than that of 6 billion people. We can safely assume nanocomputers will be used, in which the case the MB’s computational capacity will be ‘ten million billion times GREATER than the DIFFERENCE between a human and a nemotode worm‘. Sufficient capacity to emulate the entire history of human thought in a couple of microseconds. The population of uploads such a system could support would be equivilent to a population of 6 billion people for every star in the Milky Way Galaxy. Other theorists like Anders Sandburg have calculated that forms of computing more advanced than rod-logic nanocomputers could achieve 10^47 bits, thereby giving enough capacity to support the biospheres of more than a thousand galaxies.

At a conservative estimate, then, the resources available to us will provide room for six hundred billion people, and orders of magnitude more if 10^47 bits can be reached. Technology as advanced as a Matrioska Brain is a result of trends already underway, like Moore’s Law, Dickerson’s Law, (which tracks the rise in our ability to solve 3D protein structures), and Bell’s Law (every decade a new class of computer emerges from a hundred-fold drop in processing power). It has been noted that technology is becoming organic and nature is becoming technologic. The latter is driven by attempts to understand the ’information technology’ of biological processes so that they can be reprogrammed for negligible senescence etc via biotechnology, or upgraded with nanotechnology. And by incorporating biological ’lifelike’ architectures, computing systems are increasingly able to guide their own self-improvement, while at the same time we increasingly think of them as extensions of our own minds. The gradual dissecting of the components and functions of the structures of the brain and the rise of programming methodologies increasingly able to model human intelligence is enabled by increasingly close collaborations between neuroscience and computer science. Progress in these areas and others are showing that the association of increasing maturity and decreasing ability is no more unavoidable than the association of pain with surgery. We can fix it. We imagine that solving the ’problem’ of aging will have negative consequences. This is true, but as we have seen these will not be the problems many people think. In particular, the objection that we lack the resources to support people with indefinite lifespans is nonsense. Economics, or the study of the allocation of scarce goods, has long driven a process known as the ’marginalization of scarcity’ in which we learn to produce goods with increasing efficiency at less cost. The tools and knowledge that will enable us to engineer indefininite lifespans will also provide tools to manage our ’local’ resources so efficiently we shall comfortably provide for hundreds of billions of uploaded people.

And yet the problem of death is only postponed by the technology of the Matrioska Brain. These pinnacles of human civilization support uploads for as long as their host star provides energy. The Sun will continue to do so for tens of billions of years, but after that how will the uploaded population persist? What knowledge must be applied in order for life to continue? This is a question best left for ’post’human civilizations to answer. The search for a cure for senescence is an incidental outcome of a much grander drive that defines us as a species; the desire to reach beyond our limits. Darwinian evolution provided us with the tools necessary to drive an autoevolutionary process from which minds enormously more powerful than ours will emerge.

Their problems are not ours to solve.

Posted by G.P. on 03/06 at 06:42 AM
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