Winston: (laughing) My real body?. How droll! No one but my neurotechnician has seen it for years! Believe me, that's not what you want. I can do much better! He fans rapidly through a thousand images, and Nellie grimaces.
Nellie: Damn it! You're just one of Winston's MI's! Where is the real Winston? I know I used the right connection!
Winston: Nellie, I'm sorry to have to tell you this. There was a transporter accident a few weeks ago in Evanston, and... well, I'm lucky they got to me in time for the full upload. I'm all of Winston that's left. The body's gone.
When Nellie contacts her friend Winston through the Internet connection in her brain, he is already, biologically speaking, dead. It is his electronic mind double, a virtual reality twin, that greets Nellie in their virtual Parisian cafe. What's surprising here is not so much the notion that human minds may someday live on inside computers after their bodies have expired. It's the fact that this vignette is closer at hand than most people realize. Within 30 years, the minds in those computers may just be our own.
The history of technology has shown over and over that as one mode of technology exhausts its potential, a new more sophisticated paradigm emerges to keep us moving at an exponential pace. Between 1910 and 1950, computer technology doubled in power every three years; between 1950 and 1966, it doubled every two years; and it has recently been doubling every year.
By the year 2020, your $1,000 personal computer will have the processing power of the human brain--20 million billion calculations per second (100 billion neurons times 1,000 connections per neuron times 200 calculations per second per connection). By 2030, it will take a village of human brains to match a $1,000 computer. By 2050, $1,000 worth of computing will equal the processing power of all human brains on earth.
Of course, achieving the processing power of the human brain is necessary but not sufficient for creating human level intelligence in a machine. But by 2030, we'll have the means to scan the human brain and re-create its design electronically.
Most people don't realize the revolutionary impact of that. The development of computers that match and vastly exceed the capabilities of the human brain will be no less important than the evolution of human intelligence itself some thousands of generations ago. Current predictions overlook the imminence of a world in which machines become more like humans--programmed with replicated brain synapses that re-create the ability to respond appropriately to human emotion, and humans become more like machines-our biological bodies and brains enhanced with billions of "nanobots," swarms of microscopic robots transporting us in and out of virtual reality. We have already started down this road: Human and machine have already begun to meld.
It starts with uploading, or scanning the brain into a computer. One scenario is invasive: One very thin slice at a time, scientists input a brain of choice--having been frozen just slightly before it was going to die--at an extremely high speed. This way, they can easily see every neuron, every connection and every neurotransmitter concentration represented in each synapse-thin layer.
Seven years ago, a condemned killer allowed his brain and body to be scanned in this way, and you can access all 10 billion bytes of him on the Internet. You can see for yourself every bone, muscle and section of gray matter in his body. But the scan is not yet at a high enough resolution to recreate the interneuronal connections, synapses and neurotransmitter concentrations that are the key to capturing the individuality within a human brain.
Our scanning machines today can clearly capture neural features as long as the scanner is very. close to the source. Within 30 years, however, we will be able to send billions of nanobots--blood cell-size scanning machines--through every capillary of the brain to create a complete noninvasive scan of every neural feature. A shot full of nanobots will someday allow the most subtle details of our knowledge, skills and personalities to be copied into a file and stored in a computer.
We can touch and feel this technology today. We just can't make the nanobots small enough, not yet anyway. But miniaturization is another one of those accelerating technology trends. We're currently shrinking the size of technology by a factor of 5.6 per linear dimension per decade, so it is conservative to say that this scenario will be feasible in a few decades. The nanobots will capture the locations, interconnections and contents of all the nerve cell bodies, axons, dendrites, presynaptic vesicles, neurotransmitter concentrations and other relevant neural components. Using high-speed wireless communication, the nanobots will then communicate with each other and with other computers that are compiling the brain-scan database.
If this seems daunting, another scanning project, that of the human genome, was also considered ambitious when it was first introduced 12 years ago. At the time, skeptics said the task would take thousands of years, given current scanning capabilities. But the project is finishing on time nevertheless because the speed with which we can sequence DNA has grown exponentially.
Brain scanning is a prerequisite to Winston and Nellie's virtual life--and apparent immortality.
In 2029, we will swallow or inject billions of nanobots into our veins to enter a three dimensional cyberspace--a virtual reality environment. Already, neural implants are used to counteract tremors from Parkinson's disease as well as multiple sclerosis. I have a deaf friend who can now hear what I'm saying because of his cochlear implant. Under development is a retinal implant that will perform a similar function for blind people, basically replacing certain visual processing circuits of the brain. Recently, scientists from Emory University placed a chip in the brain of a paralyzed stroke victim who can now begin to communicate and control his environment directly from his brain.
But while a surgically introduced neural implant can be placed in only one or at most a few locations, nanobots can take up billions or trillions of positions throughout the brain. We already have electronic devices called neuron transistors that, noninvasively, allow communication between electronics and biological neurons. Using this technology, developed at Germany's Max Planck Institute of Biochemistry, scientists were recently able to control from their computer the movements of a living leech.
By taking up positions next to specific neurons, the nanobots will be able to detect and control their activity. For virtual reality applications, the nanobots will take up positions next to every nerve fiber coming from all five of our senses. When we want to enter a specific virtual environment, the nanobots will suppress the signals coming from our real senses and replace them with new, virtual ones. We can then cause our virtual body to move, speak and otherwise interact in the virtual environment. The nanobots would prevent our real bodies from moving; instead, we would have a virtual body in a virtual environment, which need not be the same as our real body.
Like the experiences Winston and Nellie enjoyed, this technology will enable us to have virtual interactions with other people--or simulated people--without requiring any equipment not already in our heads. And virtual reality will not be as crude as what you experience in today's arcade games. It will be as detailed and subtle as real life. So instead of just phoning a friend, you can meet in a virtual Italian bistro or stroll down a virtual tropical beach, and it will all seem real. People will be able to share any type of experience--business, social, romantic or sexual--regardless of physical proximity.
The trip to virtual reality will be readily reversible since, with your thoughts alone, you will be able to shut the nanobots off, or even direct them to leave your body. Nanobots are programmable, in that they can provide virtual reality one minute and a variety of brain extensions the next. They can change their configuration, and even alter their software.
While the combination of human-level intelligence in a machine and a computer's inherent superiority in the speed, accuracy and sharing ability of its memory will be formidable--this is not an alien invasion. It is emerging from within our human-machine civilization.
But will virtual life and its promise of immortality obviate the fear of death? Once we upload our knowledge, memories and insights into a computer, will we have acquired eternal life? First we must determine what human life is. What is consciousness anyway? If my thoughts, knowledge, experience, skills and memories achieve eternal life without me, what does that mean for me?
Consciousness--a seemingly basic tenet of "living"--is perplexing and reflects issues that have been debated since the Platonic dialogues. We assume, for instance, that other humans are conscious, but when we consider the possibility that nonhuman animals may be conscious, our understanding of consciousness is called into question.
The issue of consciousness will become even more contentious in the 21st century because nonbiological entities--read: machines--will be able to convince most of us that they are conscious. They will master all the subtle cues that we now use to determine that humans are conscious. And they will get mad if we refute their claims.
Consider this: If we scan me, for example, and record the exact state, level and position of my every neurotransmitter, synapse, neural connection and other relevant details, and then reinstantiate this massive database into a neural computer, then who is the real me? If you ask the machine, it will vehemently claim to be the original Ray. Since it will have all of my memories, it will say, "I grew up in Queens, New York, went to college at MIT, stayed in the Boston area, sold a few artificial intelligence companies, walked into a scanner there and woke up in the machine here. Hey, this technology really works."
But there are strong arguments that this is really a different person. For one thing, old biological Ray (that's me) still exists. I'll still be here in my carbon, cell-based brain. Alas, I (the old biological Ray) will have to sit back and watch the new Ray succeed in endeavors that I could only dream of. But New Ray will have some strong claims as well. He will say that while he is not absolutely identical to Old Ray, neither is the current version of Old Ray, since the particles making up my biological brain and body are constantly changing. It is the patterns of matter and energy that are semipermanent (that is, changing only gradually), while the actual material content changes constantly and very quickly.
Viewed in this way, my identity is rather like the pattern that water makes when rushing around a rock in a stream. The pattern remains relatively unchanged for hours, even years, while the actual material constituting the pattern--the water--is replaced in milliseconds.
This idea is consistent with the philosophical notion that we should not associate our fundamental identity with a set of particles, but rather with the pattern of matter and energy that we represent. In other words, if we change our definition of consciousness to value patterns over particles, then New Ray may have an equal claim to be the continuation of Old Ray.
One could scan my brain and reinstantiate the new Ray while ! was sleeping, and I would not necessarily even know about it. If you then came to me, and said, "Good news, Ray, we've successfully reinstantiated your mind file so we won't be needing your old body and brain anymore," I may quickly realize the philosophical flaw in the argument that New Ray is a continuation of my consciousness. I may wish New Ray well, and realize that he shares my pattern, but I would nonetheless conclude that he is not me, because I'm still here.
Wherever you wind up on this debate, it is worth noting that data do not necessarily last forever. The longevity, of information depends on its relevance, utility and accessibility. If you've ever tried to retrieve information from an obsolete form of data storage in an old obscure format (e.g., a reel of magnetic tape from a 1970s minicomputer), you understand the challenge of keeping software viable. But if we are diligent in maintaining our mind file, keeping current backups and porting to the latest formats and mediums, then at least a crucial aspect of who we are will attain a longevity independent of our bodies.
What does this super technological intelligence mean for the future? There will certainly be grave dangers associated with 21st century technologies. Consider unrestrained nanobot replication. The technology requires billions or trillions of nanobots in order to be useful, and the most cost-effective way to reach such levels is through self-replication, essentially the same approach used in the biological world, by bacteria, for example. So in the same way that biological self-replication gone awry (i.e., cancer) results in biological destruction, a defect in the mechanism curtailing nanobot self-replication would endanger all physical entities, biological or otherwise.
Other salient questions are: Who is controlling the nanobots? Who else might the nanobots be talking to?
Organizations, including governments, extremist groups or even a clever individual, could put trillions of undetectable nanobots in the water or food supply of an entire population. These "spy" nanobots could then monitor, influence and even control our thoughts and actions. In addition, authorized nanobots could be influenced by software viruses and other hacking techniques. Just as technology poses dangers today, there will be a panoply of risks in the decades ahead.
On a personal level, I am an optimist, and I expect that the creative and constructive applications of this technology will persevere, as I believe they do today. But there will be a valuable and increasingly vocal role for a concerned movement of Luddites--those anti-technologists inspired by early 19th century weavers who in protest destroyed machinery that was threatening their livelihood.
Still, I regard the freeing of the human mind from its severe physical limitations as a necessary next step in evolution. Evolution, in my view, is the purpose of life, meaning that the purpose of life--and of our lives--is to evolve.
What does it mean to evolve? Evolution moves toward greater complexity, elegance, intelligence, beauty, creativity and love. And God has been called all these things, only without any limitation, infinite. While evolution never reaches an infinite level, it advances exponentially, certainly moving in that direction. Technological evolution, therefore, moves us inexorably closer to becoming like God. And the freeing of our thinking from the severe limitations of our biological form may be regarded as an essential spiritual quest.
By the close of the next century, nonbiological intelligence will be ubiquitous. There will be few humans without some form of artificial intelligence, which is growing at a double exponential rate, whereas biological intelligence is basically at a standstill. Nonbiological thinking will be trillions of trillions of times more powerful than that of its biological progenitors, although it will be still of human origin.
Ultimately, however, the earth's technology-creating species will merge with its own computational technology. After all, what is the difference between a human brain enhanced a trillion-fold by nanobot-based implants, and a computer whose design is based on high-resolution scans of the human brain, and then extended a trillion-fold?
This may be the ominous, existential question that our own children, certainly our grandchildren, will face. But at this point, there's no turning back. And there's no slowing down.
Adapted by Ph.D.
Ray Kurzweil, Ph.D., an award-winning inventor and high-tech entrepreneur, developed the world's first print-to-speech reading machine for the blind and the first music synthesizer capable of re-creating the grand piano, among other technologies. He is author of The Age of Spiritual Machines: When Computers Exceed Human Intelligence, (Viking, 1999).