Part 8 (2/2)
We have demonstrated that our ability to build detailed models and working simulations of subcellular portions, neurons, and extensive neural regions follows closely upon the availability of the requisite tools and data. The performance of neurons and subcellular portions of neurons often involves substantial complexity and numerous nonlinearities, but the performance of neural cl.u.s.ters and neuronal regions is often simpler than their const.i.tuent parts. We have increasingly powerful mathematical tools, implemented in effective computer software, that are able to accurately model these types of complex hierarchical, adaptive, semirandom, self-organizing, highly nonlinear systems. Our success to date in effectively modeling several important regions of the brain shows the effectiveness of this approach.
The generation of scanning tools now emerging will for the first time provide spatial and temporal resolution capable of observing in real time the performance of individual dendrites, spines, and synapses. These tools will quickly lead to a new generation of higher-resolution models and simulations.
Once the nan.o.bot era arrives in the 2020s we will be able to observe all of the relevant features of neural performance with very high resolution from inside the brain itself. Sending billions of nan.o.bots through its capillaries will enable us to noninvasively scan an entire working brain in real time. We have already created effective (although still incomplete) models of extensive regions of the brain with today's relatively crude tools. Within twenty years, we will have at least a millionfold increase in computational power and vastly improved scanning resolution and bandwidth. So we can have confidence that we will have the data-gathering and computational tools needed by the 2020s to model and simulate the entire brain, which will make it possible to combine the principles of operation of human intelligence with the forms of intelligent information processing that we have derived from other AI research. We will also benefit from the inherent strength of machines in storing, retrieving, and quickly sharing ma.s.sive amounts of information. We will then be in a position to implement these powerful hybrid systems on computational platforms that greatly exceed the capabilities of the human brain's relatively fixed architecture.
The Scalability of Human Intelligence. In response to Hofstadter's concern as to whether human intelligence is just above or below the threshold necessary for ”self-understanding,” the accelerating pace of brain reverse engineering makes it clear that there are no limits to our ability to understand ourselves-or anything else, for that matter. The key to the scalability of human intelligence is our ability to build models of reality in our mind. These models can be recursive, meaning that one model can include other models, which can include yet finer models, without limit. For example, a model of a biological cell can include models of the nucleus, ribosomes, and other cellular systems. In turn, the model of the ribosome may include models of its submolecular components, and then down to the atoms and subatomic particles and forces that it comprises. In response to Hofstadter's concern as to whether human intelligence is just above or below the threshold necessary for ”self-understanding,” the accelerating pace of brain reverse engineering makes it clear that there are no limits to our ability to understand ourselves-or anything else, for that matter. The key to the scalability of human intelligence is our ability to build models of reality in our mind. These models can be recursive, meaning that one model can include other models, which can include yet finer models, without limit. For example, a model of a biological cell can include models of the nucleus, ribosomes, and other cellular systems. In turn, the model of the ribosome may include models of its submolecular components, and then down to the atoms and subatomic particles and forces that it comprises.
Our ability to understand complex systems is not necessarily hierarchical. A complex system like a cell or the human brain cannot be understood simply by breaking it down into const.i.tuent subsystems and their components. We have increasingly sophisticated mathematical tools for understanding systems that combine both order and chaos-and there is plenty of both in a cell and in the brain-and for understanding the complex interactions that defy logical breakdown.
Our computers, which are themselves accelerating, have been a critical tool in enabling us to handle increasingly complex models, which we would otherwise be unable to envision with our brains alone. Clearly, Hofstadter's concern would be correct if we were limited just to models that we could keep in our minds without technology to a.s.sist us. That our intelligence is just above the threshold necessary to understand itself results from our native ability, combined with the tools of our own making, to envision, refine, extend, and alter abstract-and increasingly subtle-models of our own observations.
Uploading the Human Brain
To become a figment of your computer's imagination.-DAVID VICTOR DE TRANSCEND, G.o.dLING'S GLOSSARY G.o.dLING'S GLOSSARY, DEFINITION OF ”UPLOAD”
A more controversial application than the scanning-the-brain-to-understand-it scenario is scanning the brain to upload it scanning the brain to upload it. Uploading a human brain means scanning all of its salient details and then reinstantiating those details into a suitably powerful computational substrate. This process would capture a person's entire personality, memory, skills, and history.
If we are truly capturing a particular person's mental processes, then the reinstantiated mind will need a body, since so much of our thinking is directed toward physical needs and desires. As I will discuss in chapter 5, by the time we have the tools to capture and re-create a human brain with all of its subtleties, we will have plenty of options for twenty-first-century bodies for both nonbiological humans and biological humans who avail themselves of extensions to our intelligence. The human body version 2.0 will include virtual bodies in completely realistic virtual environments, nanotechnology-based physical bodies, and more.
In chapter 3 I discussed my estimates for the memory and computational requirements to simulate the human brain. Although I estimated that 1016 cps of computation and 10 cps of computation and 1013 bits of memory are sufficient to emulate human levels of intelligence, my estimates for the requirements of uploading were higher: 10 bits of memory are sufficient to emulate human levels of intelligence, my estimates for the requirements of uploading were higher: 1019 cps and 10 cps and 1018 bits, respectively. The reason for the higher estimates is that the lower ones are based on the requirements to re-create regions of the brain at human levels of performance, whereas the higher ones are based on capturing the salient details of each of our approximately 10 bits, respectively. The reason for the higher estimates is that the lower ones are based on the requirements to re-create regions of the brain at human levels of performance, whereas the higher ones are based on capturing the salient details of each of our approximately 1011 neurons and 10 neurons and 1014 interneuronal connections. Once uploading is feasible, we are likely to find that hybrid solutions are adequate. For example, we will probably find that it is sufficient to simulate certain basic support functions such as the signal processing of sensory data on a functional basis (by plugging in standard modules) and reserve the capture of subneuron details only for those regions that are truly responsible for individual personality and skills. Nonetheless, we will use our higher estimates for this discussion. interneuronal connections. Once uploading is feasible, we are likely to find that hybrid solutions are adequate. For example, we will probably find that it is sufficient to simulate certain basic support functions such as the signal processing of sensory data on a functional basis (by plugging in standard modules) and reserve the capture of subneuron details only for those regions that are truly responsible for individual personality and skills. Nonetheless, we will use our higher estimates for this discussion.
The basic computational resources (1019 cps and 10 cps and 1018 bits) will be available for one thousand dollars in the early 2030s, about a decade later than the resources needed for functional simulation. The scanning requirements for uploading are also more daunting than for ”merely” re-creating the overall powers of human intelligence. In theory one could upload a human brain by capturing all the necessary details without necessarily comprehending the brain's overall plan. In practice, however, this is unlikely to work. Understanding the principles of operation of the human brain will reveal which details are essential and which details are intended to be disordered. We need to know, for example, which molecules in the neurotransmitters are critical, and whether we need to capture overall levels, position and location, and/or molecular shape. As I discussed above, we are just learning, for example, that it is the position of actin molecules and the shape of ePEB molecules in the synapse that are key for memory. It will not be possible to confirm which details are crucial without having confirmed our understanding of the theory of operation. That confirmation will be in the form of a functional simulation of human intelligence that pa.s.ses the Turing test, which I believe will take place by 2029. bits) will be available for one thousand dollars in the early 2030s, about a decade later than the resources needed for functional simulation. The scanning requirements for uploading are also more daunting than for ”merely” re-creating the overall powers of human intelligence. In theory one could upload a human brain by capturing all the necessary details without necessarily comprehending the brain's overall plan. In practice, however, this is unlikely to work. Understanding the principles of operation of the human brain will reveal which details are essential and which details are intended to be disordered. We need to know, for example, which molecules in the neurotransmitters are critical, and whether we need to capture overall levels, position and location, and/or molecular shape. As I discussed above, we are just learning, for example, that it is the position of actin molecules and the shape of ePEB molecules in the synapse that are key for memory. It will not be possible to confirm which details are crucial without having confirmed our understanding of the theory of operation. That confirmation will be in the form of a functional simulation of human intelligence that pa.s.ses the Turing test, which I believe will take place by 2029.119 To capture this level of detail will require scanning from within the brain using nan.o.bots, the technology for which will be available by the late 2020s. Thus, the early 2030s is a reasonable time frame for the computational performance, memory, and brain-scanning prerequisites of uploading. Like any other technology, it will take some iterative refinement to perfect this capability, so the end of the 2030s is a conservative projection for successful uploading.
We should point out that a person's personality and skills do not reside only in the brain, although that is their princ.i.p.al location. Our nervous system extends throughout the body, and the endocrine (hormonal) system has an influence, as well. The vast majority of the complexity, however, resides in the brain, which is the location of the bulk of the nervous system. The bandwidth of information from the endocrine system is quite low, because the determining factor is overall levels of hormones, not the precise location of each hormone molecule.
Confirmation of the uploading milestone will be in the form of a ”Ray Kurzweil” or ”Jane Smith” Turing test, in other words convincing a human judge that the uploaded re-creation is indistinguishable from the original specific person. By that time we'll face some complications in devising the rules of any Turing test. Since nonbiological intelligence will have pa.s.sed the original Turing test years earlier (around 2029), should we allow a nonbiological human equivalent to be a judge? How about an enhanced human? Unenhanced humans may become increasingly hard to find. In any event, it will be a slippery slope to define enhancement, as many different levels of extending biological intelligence will be available by the time we have purported uploads. Another issue will be that the humans we seek to upload will not be limited to their biological intelligence. However, uploading the nonbiological portion of intelligence will be relatively straightforward, since the ease of copying computer intelligence has always represented one of the strengths of computers.
One question that arises is, How quickly do we need to scan a person's nervous system? It clearly cannot be done instantaneously, and even if we did provide a nan.o.bot for each neuron, it would take time to gather the data. One might therefore object that because a person's state is changing during the data-gathering process, the upload information does not accurately reflect that person at an instant in time but rather over a period of time, even if only a fraction of a second.120 Consider, however, that this issue will not interfere with an upload's pa.s.sing a ”Jane Smith” Turing test. When we encounter one another on a day-to-day basis, we are recognized as ourselves even though it may have been days or weeks since the last such encounter. If an upload is sufficiently accurate to re-create a person's state within the amount of natural change that a person undergoes in a fraction of a second or even a few minutes, that will be sufficient for any conceivable purpose. Some observers have interpreted Roger Penrose's theory of the link between quantum computing and consciousness (see chapter 9) to mean that uploading is impossible because a person's ”quantum state” will have changed many times during the scanning period. But I would point out that my quantum state has changed many times in the time it took me to write this sentence, and I still consider myself to be the same person (and no one seems to be objecting). Consider, however, that this issue will not interfere with an upload's pa.s.sing a ”Jane Smith” Turing test. When we encounter one another on a day-to-day basis, we are recognized as ourselves even though it may have been days or weeks since the last such encounter. If an upload is sufficiently accurate to re-create a person's state within the amount of natural change that a person undergoes in a fraction of a second or even a few minutes, that will be sufficient for any conceivable purpose. Some observers have interpreted Roger Penrose's theory of the link between quantum computing and consciousness (see chapter 9) to mean that uploading is impossible because a person's ”quantum state” will have changed many times during the scanning period. But I would point out that my quantum state has changed many times in the time it took me to write this sentence, and I still consider myself to be the same person (and no one seems to be objecting).
n.o.bel Prize winner Gerald Edelman points out that there is a difference between a capability and a description of that capability. A photograph of a person is different from the person herself, even if the ”photograph” is very high resolution and three-dimensional. However, the concept of uploading goes beyond the extremely high-resolution scan, which we can consider the ”photograph” in Edelman's a.n.a.logy. The scan does need to capture all of the salient details, but it also needs to be instantiated into a working computational medium that has the capabilities of the original (albeit that the new nonbiological platforms are certain to be far more capable). The neural details need to interact with one another (and with the outside world) in the same ways that they do in the original. A comparable a.n.a.logy is the comparison between a computer program that resides on a computer disk (a static picture) and a program that is actively running on a suitable computer (a dynamic, interacting ent.i.ty). Both the data capture and the reinstantiation of a dynamic ent.i.ty const.i.tute the uploading scenario.
Perhaps the most important question will be whether or not an uploaded human brain is really you. Even if the upload pa.s.ses a personalized Turing test and is deemed indistinguishable from you, one could still reasonably ask whether the upload is the same person or a new person. After all, the original person may still exist. I'll defer these essential questions until chapter 7.
In my view the most important element in uploading will be our gradual transfer of our intelligence, personality, and skills to the nonbiological portion of our intelligence. We already have a variety of neural implants. In the 2020s we will use nan.o.bots to begin augmenting our brains with nonbiological intelligence, starting with the ”routine” functions of sensory processing and memory, moving on to skill formation, pattern recognition, and logical a.n.a.lysis. By the 2030s the nonbiological portion of our intelligence will predominate, and by the 2040s, as I pointed out in chapter 3, the nonbiological portion will be billions of times more capable. Although we are likely to retain the biological portion for a period of time, it will become of increasingly little consequence. So we will have effectively uploaded ourselves, albeit gradually, never quite noticing the transfer. There will be no ”old Ray” and ”new Ray,” just an increasingly capable Ray. Although I believe that uploading as in the sudden scan-and-transfer scenario discussed in this section will be a feature of our future world, it is this gradual but inexorable progression to vastly superior nonbiological thinking that will profoundly transform human civilization.
SIGMUND FREUD: When you talk about reverse engineering the human brain, just whose brain are you talking about? A man's brain? A woman's? A child's? The brain of a genius? A r.e.t.a.r.ded individual? An ”idiot savant”? A gifted artist? A serial murderer? When you talk about reverse engineering the human brain, just whose brain are you talking about? A man's brain? A woman's? A child's? The brain of a genius? A r.e.t.a.r.ded individual? An ”idiot savant”? A gifted artist? A serial murderer?
RAY: Ultimately, we're talking about all of the above. There are basic principles of operation that we need to understand about how human intelligence and its varied const.i.tuent skills work. Given the human brain's plasticity, our thoughts literally create our brains through the growth of new spines, synapses, dendrites, and even neurons. As a result, Einstein's parietal lobes-the region a.s.sociated with visual imagery and mathematical thinking-became greatly enlarged. Ultimately, we're talking about all of the above. There are basic principles of operation that we need to understand about how human intelligence and its varied const.i.tuent skills work. Given the human brain's plasticity, our thoughts literally create our brains through the growth of new spines, synapses, dendrites, and even neurons. As a result, Einstein's parietal lobes-the region a.s.sociated with visual imagery and mathematical thinking-became greatly enlarged. However, there is only so much room in our skulls, so although Einstein played music he was not a world-cla.s.s musician. Pica.s.so did not write great poetry, and so on. As we re-create the human brain, we will not be limited in our ability to develop each skill. We will not have to compromise 'one area to enhance another. However, there is only so much room in our skulls, so although Einstein played music he was not a world-cla.s.s musician. Pica.s.so did not write great poetry, and so on. As we re-create the human brain, we will not be limited in our ability to develop each skill. We will not have to compromise 'one area to enhance another.
We can also gain insight into our differences and an understanding of human dysfunction. What went wrong with the serial murderer? It must, after all, have something to do with his brain. This type of disastrous behavior is clearly not the result of indigestion.
MOLLY 2004: You know, I doubt it's just the brains we're born with that account for our differences. What about our struggles through life, and all this stuff I'm trying to learn? You know, I doubt it's just the brains we're born with that account for our differences. What about our struggles through life, and all this stuff I'm trying to learn?
RAY: Yes, well, that's part of the paradigm, too, isn't it? We have brains that can learn, starting from when we learn to walk and talk to when we study college chemistry. Yes, well, that's part of the paradigm, too, isn't it? We have brains that can learn, starting from when we learn to walk and talk to when we study college chemistry.
MARVIN MINSKY: It's true that educating our AIs will be an important part of the process, but we can automate a lot of that and greatly speed it up. Also, keep in mind that when one AI learns something, it can quickly share that knowledge with many other AIs. It's true that educating our AIs will be an important part of the process, but we can automate a lot of that and greatly speed it up. Also, keep in mind that when one AI learns something, it can quickly share that knowledge with many other AIs.
RAY: They'll have access to all of our exponentially growing knowledge on the Web, which will include habitable, full-immersion virtual-reality environments where they can interact with one another and with biological humans who are projecting themselves into these environments. They'll have access to all of our exponentially growing knowledge on the Web, which will include habitable, full-immersion virtual-reality environments where they can interact with one another and with biological humans who are projecting themselves into these environments.
SIGMUND: These AIs don't have bodies yet. As we have both pointed out, human emotion and much of our thinking are directed at our bodies and to meeting their sensual and s.e.xual needs. These AIs don't have bodies yet. As we have both pointed out, human emotion and much of our thinking are directed at our bodies and to meeting their sensual and s.e.xual needs.
RAY: Who says they won't have bodies? As I will discuss in the human body version 2.0 section in chapter 6, we'll have the means of creating nonbiological yet humanlike bodies, as well as virtual bodies in virtual reality. Who says they won't have bodies? As I will discuss in the human body version 2.0 section in chapter 6, we'll have the means of creating nonbiological yet humanlike bodies, as well as virtual bodies in virtual reality.
SIGMUND: But a virtual body is not a real body. But a virtual body is not a real body.
RAY: The word ”virtual” is somewhat unfortunate. It implies ”not real,” but the reality will be that a virtual body is just as real as a physical body in all the ways that matter. Consider that the telephone is auditory virtual reality. No one feels that his voice in this virtual-reality environment is not a ”real” voice. With my physical body today, I don't directly experience someone's touch on my arm. My brain receives processed signals initiated by nerve endings in my arm, which wind their way through the spinal cord, through the brain stem, and up to the insula regions. If my brain-or an AI's brain-receives comparable signals of someone's virtual touch on a virtual arm, there's no discernible difference. The word ”virtual” is somewhat unfortunate. It implies ”not real,” but the reality will be that a virtual body is just as real as a physical body in all the ways that matter. Consider that the telephone is auditory virtual reality. No one feels that his voice in this virtual-reality environment is not a ”real” voice. With my physical body today, I don't directly experience someone's touch on my arm. My brain receives processed signals initiated by nerve endings in my arm, which wind their way through the spinal cord, through the brain stem, and up to the insula regions. If my brain-or an AI's brain-receives comparable signals of someone's virtual touch on a virtual arm, there's no discernible difference.
MARVIN: Keep in mind that not all AIs will need human bodies. Keep in mind that not all AIs will need human bodies.
RAY: Indeed. As humans, despite some plasticity, both our bodies and brains have a relatively fixed architecture. Indeed. As humans, despite some plasticity, both our bodies and brains have a relatively fixed architecture.
MOLLY 2004: Yes, it's called being human, something you seem to have a problem with. Yes, it's called being human, something you seem to have a problem with.
RAY: Actually, I often do have a problem with all the limitations and maintenance that my version 1.0 body requires, not to mention all the limitations of my brain. But I do appreciate the joys of the human body. My point is that AIs can and will have the equivalent of human bodies in both real and virtual-reality environments. As Marvin points out, however, they will not be limited just to this. Actually, I often do have a problem with all the limitations and maintenance that my version 1.0 body requires, not to mention all the limitations of my brain. But I do appreciate the joys of the human body. My point is that AIs can and will have the equivalent of human bodies in both real and virtual-reality environments. As Marvin points out, however, they will not be limited just to this.
MOLLY 2104: It's not just AIs that will be liberated from the limitations of version 1.a bodies. Humans of biological origin will have the same freedom in both real and virtual reality. It's not just AIs that will be liberated from the limitations of version 1.a bodies. Humans of biological origin will have the same freedom in both real and virtual reality.
GEORGE 2048: Keep in mind, there won't be a clear distinction between AIs and humans. Keep in mind, there won't be a clear distinction between AIs and humans.
MOLLY 2104: Yes, except for the MOSHs (Mostly Original Substrate Humans) of course. Yes, except for the MOSHs (Mostly Original Substrate Humans) of course.
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