Physics of the Future_ How Science Will Shape Human Destiny... Part 5

But when you enter the USC lab, you see something quite different. You see boxes of cubical modules, each about 2 inches square, that can join or separate, allowing you to create a variety of animal-like creatures. You can create snakes that slither in a line. Or rings that can roll like a hoop. But then you can twist these cubes or hook them up with Y-shaped joints, so you can create an entirely new set of devices resembling octopi, spiders, dogs, or cats. Think of a smart Lego set, with each block being intelligent and capable of arranging itself in any configuration imaginable.

This would be useful for going past barriers. If a spider-shaped robot was crawling in the sewer system and encountered a wall, it would first find a tiny hole in the wall and then disa.s.semble itself. Each piece would go through the hole, and then the pieces would rea.s.semble themselves on the other side of the wall. In this way, these modular robots would be nearly unstoppable, able to negotiate most obstacles.

These modular robots might be crucial in repairing our decaying infrastructure. In 2007, for example, the Mississippi River bridge in Minneapolis collapsed, killing 13 people and injuring 145, probably because the bridge was aging, overloaded, and had design flaws. There are perhaps hundreds of similar accidents waiting to happen across the country, but it simply costs too much money to monitor every decaying bridge and make repairs. This is where modular robots may come to the rescue, silently checking our bridges, roads, tunnels, pipes, and power stations, and making repairs when necessary. (For example, the bridges into lower Manhattan have suffered greatly due to corrosion, neglect, and lack of repairs. One worker found a 1950s c.o.ke bottle left over from when the bridges were last painted. In fact, one section of the aging Manhattan Bridge came dangerously close to collapse recently and had to be shut down for repairs.) ROBOT SURGEONS AND COOKS.

Robots may be used as surgeons as well as cooks and musicians. For example, one important limitation of surgery is the dexterity and accuracy of the human hand. Surgeons, like all people, become fatigued after many hours and their efficiency drops. Fingers begin to tremble. Robots may solve these problems.

For example, traditional surgery for a heart bypa.s.s operation involves opening a foot-long gash in the middle of the chest, which requires general anesthesia. Opening the chest cavity increases the possibility of infection and the length of time for recovery, creates intense pain and discomfort during the healing process, and leaves a disfiguring scar. But the da Vinci robotic system can vastly decrease all these. The da Vinci robot has four robotic arms, one for manipulating a video camera and three for precision surgery. Instead of making a long incision in the chest, it makes only several tiny incisions in the side of the body. There are 800 hospitals in Europe and North and South America that use this system; 48,000 operations were performed in 2006 alone with this robot. Surgery can also be done by remote control over the Internet, so a world-cla.s.s surgeon in a major city can perform surgery on a patient in an isolated rural area on another continent.

In the future, more advanced versions will be able to perform surgery on microscopic blood vessels, nerve fibers, and tissues by manipulating microscopic scalpels, tweezers, and needles, which is impossible today. In fact, in the future, only rarely will the surgeon slice the skin at all. Noninvasive surgery will become the norm.

Endoscopes (long tubes inserted into the body that can illuminate and cut tissue) will be thinner than thread. Micromachines smaller than the period at the end of this sentence will do much of the mechanical work. (In one episode of the original Star Trek, Star Trek, Doctor McCoy was totally revolted that doctors in the twentieth century had to cut skin.) The day when this is a reality is coming soon. Doctor McCoy was totally revolted that doctors in the twentieth century had to cut skin.) The day when this is a reality is coming soon.

Medical students in the future will learn to slice up 3-D virtual images of the human body, where each movement of the hand is reproduced by a robot in another room.

The j.a.panese have also excelled at producing robots that can interact socially with humans. In Nagoya, there is the robot chef that can create a standard fast-food dinner in a few minutes. You simply punch in what you want from a menu and the robot chef produces your meal in front of you. Built by Aisei, an industrial robotics company, this robot can cook noodles in 1 minute and 40 seconds and can serve 80 bowls on a busy day. The robot chef looks very much like ones on the automobile a.s.sembly lines in Detroit. You have two large mechanical arms, which are precisely programmed to move in a certain sequence. Instead of s.c.r.e.w.i.n.g and welding metal in a factory, however, these robotic fingers grab ingredients from a series of bowls containing dressing, meat, flour, sauces, spices, etc. The robotic arms mix and then a.s.semble them into a sandwich, salad, or soup. The Aisei cook looks like a robot, resembling two gigantic hands emerging from the kitchen counter. But other models being planned start to look more human.

Also in j.a.pan, Toyota has created a robot that can play the violin almost as well as any professional. It resembles ASIMO, except that it can grab a violin, sway with the music, and then delicately play complex violin pieces. The sound is amazingly realistic and the robot can make grand gestures like a master musician. Although the music is not yet at the level of a concert violinist, it is good enough to entertain audiences. Of course, in the last century, we have had mechanical piano machines that played tunes inscribed on a large rotating disk. Like these piano machines, the Toyota machine is also programmed. But the difference is that the Toyota machine is deliberately designed to mimic all the positions and postures of a human violinist in the most realistic way.

Also, at Waseda University in j.a.pan, scientists have made a robotic flutist. The robot contains hollow chambers in its chest, like lungs, which blow air over a real flute. It can play quite complex melodies like "The Flight of the b.u.mblebee." These robots cannot create new music, we should emphasize, but they can rival a human in their ability to perform music.

The robot chef and robot musician are carefully programmed. They are not autonomous. Although these robots are quite sophisticated compared to the old player pianos, they still operate on the same principles. True robot maids and butlers are still in the distant future. But the descendants of the robot chef and the robot violinist and flutist may one day find themselves embedded in our lives, performing basic functions that were once thought to be exclusively human.

EMOTIONAL ROBOTS.

By midcentury, the era of emotional robots may be in full flower.

In the past, writers have fantasized about robots that yearn to become human and have emotions. In Pinocchio, Pinocchio, a wooden puppet wished to become a real boy. In the a wooden puppet wished to become a real boy. In the Wizard of Oz, Wizard of Oz, the Tin Man wished for a heart. And in the Tin Man wished for a heart. And in Star Trek: The Next Generation, Star Trek: The Next Generation, Data the android tried to master emotions by telling jokes and figuring out what makes us laugh. In fact, in science fiction, it is a recurring theme that although robots may become increasingly intelligent, the essence of emotions will always elude them. Robots may one day become smarter than us, some science fiction writers declare, but they won't be able to cry. Data the android tried to master emotions by telling jokes and figuring out what makes us laugh. In fact, in science fiction, it is a recurring theme that although robots may become increasingly intelligent, the essence of emotions will always elude them. Robots may one day become smarter than us, some science fiction writers declare, but they won't be able to cry.

Actually, that may not be true. Scientists are now understanding the true nature of emotions. First, emotions tell us what is good for us and what is harmful. The vast majority of things in the world are either harmful or not very useful. When we experience the emotion of "like," we are learning to identify the tiny fraction of things in the environment that are beneficial to us.

In fact, each of our emotions (hate, jealousy, fear, love, etc.) evolved over millions of years to protect us from the dangers of a hostile world and help us to reproduce. Every emotion helps to propagate our genes into the next generation.

The critical role of emotions in our evolution was apparent to neurologist Antonio Damasio of the University of Southern California, who a.n.a.lyzed victims of brain injuries or disease. In some of these patients, the link between the thinking part of their brains (the cerebral cortex) and the emotional center (located deep in the center of the brain, like the amygdala) was cut. These people were perfectly normal, except they had difficulty expressing emotions.

One problem became immediately obvious: they could not make choices. Shopping was a nightmare, since everything had the same value to them, whether it was expensive or cheap, garish or sophisticated. Setting an appointment was almost impossible, since all dates in the future were the same. They seem "to know, but not to feel," he said.

In other words, one of the chief purposes of emotions is to give us values, so we can decide what is important, what is expensive, what is pretty, and what is precious. Without emotions, everything has the same value, and we become paralyzed by endless decisions, all of which have the same weight. So scientists are now beginning to understand that emotions, far from being a luxury, are essential to intelligence.

For example, when one watches Star Trek Star Trek and sees Spock and Data performing their jobs supposedly without any emotions, you now realize the flaw immediately. At every turn, Spock and Data have exhibited emotions: they have made a long series of value judgments. They decided that being an officer is important, that it is crucial to perform certain tasks, that the goal of the Federation is a n.o.ble one, that human life is precious, etc. So it is an illusion that you can have an officer devoid of emotions. and sees Spock and Data performing their jobs supposedly without any emotions, you now realize the flaw immediately. At every turn, Spock and Data have exhibited emotions: they have made a long series of value judgments. They decided that being an officer is important, that it is crucial to perform certain tasks, that the goal of the Federation is a n.o.ble one, that human life is precious, etc. So it is an illusion that you can have an officer devoid of emotions.

Emotional robots could also be a matter of life and death. In the future, scientists may be able to create rescue robots-robots that are sent into fires, earthquakes, explosions, etc. They will have to make thousands of value judgments about who and what to save and in what order. Surveying the devastation all around them, they will have to rank the various tasks they face in order of priority.

Emotions are also essential if you view the evolution of the human brain. If you look at the gross anatomical features of the brain, you notice that they can be grouped into three large categories.

First, you have the reptilian brain, found near the base of the skull, which makes up most of the brain of reptiles. Primitive life functions, such as balance, aggression, territoriality, searching for food, etc., are controlled by this part of the brain. (Sometimes, when staring at a snake that is staring back at you, you get a creepy sensation. You wonder, What is the snake thinking about? If this theory is correct, then the snake is not thinking much at all, except whether or not you are lunch.) When we look at higher organisms, we see that the brain has expanded toward the front of the skull. At the next level, we find the monkey brain, or the limbic system, located in the center of our brain. It includes components like the amygdala, which is involved in processing emotions. Animals that live in groups have an especially well-developed limbic system. Social animals that hunt in groups require a high degree of brainpower devoted to understanding the rules of the pack. Since success in the wilderness depends on cooperating with others, but because these animals cannot talk, it means that these animals must communicate their emotional state via body language, grunts, whines, and gestures.

Finally, we have the front and outer layer of the brain, the cerebral cortex, the layer that defines humanity and governs rational thought. While other animals are dominated by instinct and genetics, humans use the cerebral cortex to reason things out.

If this evolutionary progression is correct, it means that emotions will play a vital role in creating autonomous robots. So far, robots have been created that mimic only the reptilian brain. They can walk, search their surroundings, and pick up objects, but not much more. Social animals, on the other hand, are more intelligent than those with just a reptilian brain. Emotions are required to socialize the animal and for it to master the rules of the pack. So scientists have a long way to go before they can model the limbic system and the cerebral cortex.

Cynthia Breazeal of MIT actually created a robot specifically designed to tackle this problem. The robot is KISMET, with a face that resembles a mischievous elf. On the surface, it appears to be alive, responding to you with facial motions representing emotions. KISMET can duplicate a wide range of emotions by changing its facial expressions. In fact, women who react to this childlike robot often speak to KISMET in "motherese," what mothers use when talking to babies and children. Although robots like KISMET are designed to mimic emotions, scientists have no illusion that the robot actually feels emotions. In some sense, it is like a tape recorder programmed not to make sounds, but to make facial emotions instead, with no awareness of what it is doing. But the breakthrough with KISMET is that it does not take much programming to create a robot that will mimic humanlike emotions to which humans will respond.

These emotional robots will find their way into our homes. They won't be our confidants, secretaries, or maids, but they will be able to perform rule-based procedures based on heuristics. By midcentury, they may have the intelligence of a dog or cat. Like a pet, they will exhibit an emotional bond with their master, so that they will not be easily discarded. You will not be able to speak to them in colloquial English, but they will understand programmed commands, perhaps hundreds of them. If you tell them to do something that is not already stored in their memory (such as "go fly a kite"), they will simply give you a curious, confused look. (If by midcentury robot dogs and cats can duplicate the full range of animal responses, indistinguishable from real animal behavior, then the question arises whether these robot animals feel or are as intelligent as an ordinary dog or cat.) Sony experimented with these emotional robots when it manufactured the AIBO (artificial intelligence robot) dog. It was the first toy to realistically respond emotionally to its master, albeit in a primitive way. For example, if you pet the AIBO dog on its back, it would immediately begin to murmur, uttering soothing sounds. It could walk, respond to voice commands, and even learn to a degree. AIBO cannot learn new emotions and emotional responses. (It was discontinued in 2005 due to financial reasons, but it has since created a loyal following who upgrade the computer's software so AIBO can perform more tasks.) In the future, robotic pets that form an emotional attachment to children may become common.

Although these robot pets will have a large library of emotions and will form lasting attachments with children, they will not feel actual emotions.

REVERSE ENGINEER THE BRAIN.

By midcentury, we should be able to complete the next milestone in the history of AI: reverse engineering the human brain. Scientists, frustrated that they have not been able to create a robot made of silicon and steel, are also trying the opposite approach: taking apart the brain, neuron by neuron-just like a mechanic might take apart a motor, screw by screw-and then running a simulation of these neurons on a huge computer. These scientists are systematically trying to simulate the firings of neurons in animals, starting with mice, cats, and going up the evolutionary scale of animals. This is a well-defined goal, and should be possible by midcentury.

MIT's Fred Hapgood writes, "Discovering how the brain works-exactly how it works, the way we know how a motor works-would rewrite almost every text in the library." how it works, the way we know how a motor works-would rewrite almost every text in the library."

The first step in the process of reverse engineering the brain is to understand its basic structure. Even this simple task has been a long, painful process. Historically, the various parts of the brain were identified during autopsies, without a clue as to their function. This gradually began to change when scientists a.n.a.lyzed people with brain damage, and noticed that damage to certain parts of the brain corresponded to changes in behavior. Stroke victims and people suffering from brain injuries or diseases exhibited specific behavior changes, which could then be matched to injuries in specific parts of the brain.

The most spectacular example of this was in 1848 in Vermont, when a 3-foot, 8-inch-long metal rod was driven right through the skull of a railroad foreman named Phineas Gage. This history-making accident happened when dynamite accidentally exploded. The rod entered the side of his face, shattered his jaw, went through his brain, and pa.s.sed out the top of his head. Miraculously, he survived this horrendous accident, although one or both of his frontal lobes were destroyed. The doctor who treated him at first could not believe that anyone could survive such an accident and still be alive. He was in a semiconscious state for several weeks, but later miraculously recovered. He even survived for twelve more years, taking odd jobs and traveling, dying in 1860. Doctors carefully preserved his skull and the rod, and they have been intensely studied ever since. Modern techniques, using CT scans, have reconstructed details of this extraordinary accident.

This event forever changed the prevailing opinions of the mind-body problem. Previously, it was believed even within scientific circles that the soul and the body were separate ent.i.ties. People wrote knowingly about some "life force" that animated the body, independent of the brain. But widely circulated reports indicated that Gage's personality underwent marked changes after the accident. Some accounts claim that Gage was a well-liked, outgoing man who became abusive and hostile after the accident. The impact of these reports reinforced the idea that specific parts of the brain controlled different behaviors, and hence the body and soul were inseparable.

In the 1930s, another breakthrough was made when neurologists like Wilder Penfield noticed that while performing brain surgery for epilepsy sufferers, when he touched parts of the brain with electrodes, certain parts of the patient's body could be stimulated. Touching this or that part of the cortex could cause a hand or leg to move. In this way, he was able to construct a crude outline of which parts of the cortex controlled which parts of the body. As a result, one could redraw the human brain, listing which parts of the brain controlled which organ. The result was a homunculus, a rather bizarre picture of the human body mapped onto the surface of the brain, which looked like a strange little man, with huge fingertips, lips, and tongue, but a tiny body.

More recently, MRI scans have given us revealing pictures of the thinking brain, but they are incapable of tracing the specific neural pathways of thought, perhaps involving only a few thousand neurons. But a new field called optogenetics combines optics and genetics to unravel specific neural pathways in animals. By a.n.a.logy, this can be compared to trying to create a road map. The results of the MRI scans would be akin to determining the large interstate highways and the large flow of traffic on them. But optogenetics might be able to actually determine individual roads and pathways. In principle, it even allows scientists the possibility of controlling animal behavior by stimulating these specific pathways.

This, in turn, generated several sensational media stories. The Drudge Report ran a lurid headline that screamed, "Scientists Create Remote-Controlled Flies." The media conjured up visions of remote-controlled flies carrying out the dirty work of the Pentagon. On the Tonight Show, Tonight Show, Jay Leno even talked about a remote-controlled fly that could fly into the mouth of President George W. Bush on command. Although comedians had a field day imagining bizarre scenarios of the Pentagon commanding h.o.a.rds of insects with the push of a b.u.t.ton, the reality is much more modest. Jay Leno even talked about a remote-controlled fly that could fly into the mouth of President George W. Bush on command. Although comedians had a field day imagining bizarre scenarios of the Pentagon commanding h.o.a.rds of insects with the push of a b.u.t.ton, the reality is much more modest.

The fruit fly has roughly 150,000 neurons in the brain. Optogenetics allows scientists to light up certain neurons in the brains of fruit flies that correspond to certain behaviors. For example, when two specific neurons are activated, it can signal the fruit fly to escape. The fly then automatically extends its legs, spreads its wings, and takes off. Scientists were able to genetically breed a strain of fruit flies whose escape neurons fired every time a laser beam was turned on. If you shone a laser beam on these fruit flies, they took off each time.

The implications for determining the structure of the brain are important. Not only would we be able to slowly tease apart neural pathways for certain behaviors, but we also could use this information to help stroke victims and patients suffering from brain diseases and accidents.

Gero Miesenbock of Oxford University and his colleagues have been able to identify the neural mechanisms of animals in this way. They can study not only the pathways for the escape reflex in fruit flies but also the reflexes involved in smelling odors. They have studied the pathways governing food-seeking in roundworms. They have studied the neurons involved in decision making in mice. They found that while as few as two neurons were involved in triggering behaviors in fruit flies, almost 300 neurons were activated in mice for decision making.

The basic tools they have been using are genes that can control the production of certain dyes, as well as molecules that react to light. For example, there is a gene from jellyfish that can make green fluorescent protein. Also, there are a variety of molecules like rhodopsin that respond when light is shone upon them by allowing ions to pa.s.s through cell membranes. In this way, s.h.i.+ning light on these organisms can trigger certain chemical reactions. Armed with these dyes and light-sensitive chemicals, these scientists have been able for the first time to tease apart neural circuits governing specific behaviors.

So although comedians like to poke fun at these scientists for trying to create Frankenstein fruit flies controlled by the push of a b.u.t.ton, the reality is that scientists are, for the first time in history, tracing the specific neural pathways of the brain that control specific behaviors.

MODELING THE BRAIN.

Optogenetics is a first, modest step. The next step is to actually model the entire brain, using the latest in technology. There are at least two ways to solve this colossal problem, which will take many decades of hard work. The first is by using supercomputers to simulate the behavior of billions of neurons, each one connected to thousands of other neurons. The other way is to actually locate every neuron in the brain.

The key to the first approach, simulating the brain, is simple: raw computer power. The bigger the computer, the better. Brute force, and inelegant theories, may be the key to cracking this gigantic problem. And the computer that might accomplish this herculean task is called Blue Gene, one of the most powerful computers on earth, built by IBM.

I had a chance to visit this monster computer when I toured the Lawrence Livermore National Laboratory in California, where they design hydrogen warheads for the Pentagon. It is America's premier top-secret weapons laboratory, a sprawling, 790-acre complex in the middle of farm country, budgeted at $1.2 billion per year and employing 6,800 people. This is the heart of the U.S. nuclear weapons establishment. I had to pa.s.s through many layers of security to see it, since this is one of the most sensitive weapons laboratories on earth.

Finally, after pa.s.sing a series of checkpoints, I gained entrance to the building housing IBM's Blue Gene computer, which is capable of computing at the blinding speed of 500 trillion operations per second. Blue Gene is a remarkable sight. It is huge, occupying about a quarter acre, and consists of row after row of jet-black steel cabinets, each one about 8 feet tall and 15 feet long.

When I walked among these cabinets, it was quite an experience. Unlike Hollywood science fiction movies, where the computers have lots of blinking lights, spinning disks, and bolts of electricity crackling through the air, these cabinets are totally quiet, with only a few tiny lights blinking. You realize that the computer is performing trillions of complex calculations, but you hear nothing and see nothing as it works.

What I was interested in was the fact that Blue Gene was simulating the thinking process of a mouse brain, which has about 2 million neurons (compared to the 100 billion neurons that we have). Simulating the thinking process of a mouse brain is harder than you think, because each neuron is connected to many other neurons, making a dense web of neurons. But while I was walking among rack after rack of consoles making up Blue Gene, I could not help but be amazed that this astounding computer power could simulate only the brain of a mouse, and then only for a few seconds. (This does not mean that Blue Gene can simulate the behavior of a mouse. At present, scientists can barely simulate the behavior of a c.o.c.kroach. Rather, this means that Blue Gene can simulate the firing of neurons found in a mouse, not its behavior.) In fact, several groups have focused on simulating the brain of a mouse. One ambitious attempt is the Blue Brain Project of Henry Markram of the ecole Polytechnique Federale de Lausanne, in Switzerland. He began in 2005, when he was able to obtain a small version of Blue Gene, with only 16,000 processors, but within a year he was successful in modeling the rat's neocortical column, part of the neocortex, which contains 10,000 neurons and 100 million connections. That was a landmark study, because it meant that it was biologically possible to completely a.n.a.lyze the structure of an important component of the brain, neuron for neuron. (The mouse brain consists of millions of these columns, repeated over and over again. Thus, by modeling one of these columns, one can begin to understand how the mouse brain works.) In 2009, Markram said optimistically, "It is not impossible to build a human brain and we can do it in ten years. If we build it correctly, it should speak and have an intelligence and behave very much as a human does." He cautions, however, that it would take a supercomputer 20,000 times more powerful than present supercomputers, with a memory storage 500 times the entire size of the current Internet, to achieve this.

So what is the roadblock preventing this colossal goal? To him, it's simple: money.

Since the basic science is known, he feels that he can succeed by simply throwing money at the problem. He says, "It's not a question of years, it's one of dollars.... It's a matter of if society wants this. If they want it in ten years, they'll have it in ten years. If they want it in a thousand years, we can wait."

But a rival group is also tackling this problem, a.s.sembling the greatest computational firepower in history. This group is using the most advanced version of Blue Gene, called Dawn, also based in Livermore. Dawn is truly an awesome sight, with 147,456 processors with 150,000 gigabytes of memory. It is roughly 100,000 times more powerful than the computer sitting on your desk. The group, led by Dharmendra Modha, has scored a number of successes. In 2006, it was able to simulate 40 percent of a mouse's brain. In 2007, it could simulate 100 percent of a rat's brain (which contains 55 million neurons, much more than the mouse brain).

And in 2009, the group broke yet another world record. It succeeded in simulating 1 percent of the human cerebral cortex, or roughly the cerebral cortex of a cat, containing 1.6 billion neurons with 9 trillion connections. However, the simulation was slow, about 1/600th the speed of the human brain. (If it simulated only a billion neurons, it went much faster, about 1/83rd the speed of the human brain.) "This is a Hubble Telescope of the mind, a linear accelerator of the brain," says Modha proudly, remarking on the mammoth scale of this achievement. Since the brain has 100 billion neurons, these scientists can now see the light at the end of the tunnel. They feel that a full simulation of the human brain is within sight. "This is not just possible, it's inevitable. This will happen," says Modha.

There are serious problems, however, with modeling the entire human brain, especially power and heat. The Dawn computer devours 1 million watts of power and generates so much heat it needs 6,675 tons of air-conditioning equipment, which blows 2.7 million cubic feet of chilled air every minute. To model the human brain, you would have to scale this up by a factor of 1,000.

This is a truly monumental task. The power consumption of this hypothetical supercomputer would be a billion watts, or the output of an entire nuclear power plant. You could light up an entire city with the energy consumed by this supercomputer. To cool it, you would need to divert an entire river and channel the water through the computer. And the computer itself would occupy many city blocks.

Amazingly, the human brain, by contrast, uses just 20 watts. The heat generated by the human brain is hardly noticeable, yet it easily outperforms our greatest supercomputer. Furthermore, the human brain is the most complex object that Mother Nature has produced in this section of the galaxy. Since we see no evidence of other intelligent life-forms in our solar system, this means that you have to go out to at least 24 trillion miles, the distance to the nearest star, and even beyond to find an object as complex as the one sitting inside your skull.

We might be able to reverse engineer the brain within ten years, but only if we had a ma.s.sive Manhattan Projectstyle crash program and dumped billions of dollars into it. However, this is not very likely to happen any time soon, given the current economic climate. Crash programs like the Human Genome Project, which cost nearly $3 billion, were supported by the U.S. government because of their obvious health and scientific benefits. However, the benefits of reverse engineering the brain are less urgent, and hence will take much longer. More realistically, we will approach this goal in smaller steps, and it may take decades to fully accomplish this historic feat.

So computer simulating the brain may take us to midcentury. And even then, it will take many decades to sort through the mountains of data pouring in from this ma.s.sive project and match it to the human brain. We will be drowning in data without the means to meaningfully sort out the noise.

TAKING APART THE BRAIN.

But what about the second approach, identifying the precise location of every neuron in the brain?

This approach is also a herculean task, and may also take many decades of painful research. Instead of using supercomputers like Blue Gene, these scientists take the slice-and-dice approach, starting by dissecting the brain of a fruit fly into incredibly thin slices no more than 50 nm wide (about 150 atoms across). This produces millions of slices. Then a scanning electron microscope takes a photograph of each, with a speed and resolution approaching a billion pixels per second. The amount of data spewing from the electron microscope is staggering, about 1,000 trillion bytes of data, enough to fill a storage room just for a single fruit fly brain. Processing this data, by tediously reconstructing the 3-D wiring of every single neuron of the fly brain, would take about five years. To get a more accurate picture of the fly brain, you then have to slice many more fly brains.

Gerry Rubin of the Howard Hughes Medical Inst.i.tute, one of the leaders in this field, thinks that altogether, a detailed map of the entire fruit fly brain will take twenty years. "After we solve this, I'd say we're one-fifth of the way to understanding the human mind," he concludes. Rubin realizes the enormity of the task he faces. The human brain has 1 million times more neurons than the brain of a fruit fly. If it takes twenty years to identify every single neuron of the fly brain, then it will certainly take many decades beyond that to fully identify the neural architecture of the human brain. The cost of this project will also be enormous.

So workers in the field of reverse engineering the brain are frustrated. They see that their goal is tantalizingly close, but the lack of funding hinders their work. However, it seems reasonable to a.s.sume that sometime by midcentury, we will have both the computer power to simulate the human brain and also crude maps of the brain's neural architecture. But it may well take until late in this century before we fully understand human thought or can create a machine that can duplicate the functions of the human brain.

For example, even if you are given the exact location of every gene inside an ant, it does not mean you know how an anthill is created. Similarly, just because scientists now know the roughly 25,000 genes that make up the human genome, it does not mean they know how the human body works. The Human Genome Project is like a dictionary with no definitions. Each of the genes of the human body is spelled out explicitly in this dictionary, but what each does is still largely a mystery. Each gene codes for a certain protein, but it is not known how most of these proteins function in the body.

Back in 1986, scientists were able to map completely the location of all the neurons in the nervous system of the tiny worm C. elegans. C. elegans. This was initially heralded as a breakthrough that would allow us to decode the mystery of the brain. But knowing the precise location of its 302 nerve cells and 6,000 chemical synapses did not produce any new understanding of how this worm functions, even decades later. This was initially heralded as a breakthrough that would allow us to decode the mystery of the brain. But knowing the precise location of its 302 nerve cells and 6,000 chemical synapses did not produce any new understanding of how this worm functions, even decades later.

In the same way, it will take many decades, even after the human brain is finally reverse engineered, to understand how all the parts work and fit together. If the human brain is finally reverse engineered and completely decoded by the end of the century, then we will have taken a giant step in creating humanlike robots. Then what is to prevent them from taking over?

WHEN MACHINES BECOME CONSCIOUS.

In The Terminator The Terminator movie series, the Pentagon proudly unveils Skynet, a sprawling, foolproof computer network designed to faithfully control the U.S. nuclear a.r.s.enal. It flawlessly carries out its tasks until one day in 1995, when something unexpected happens. Skynet becomes conscious. Skynet's human handlers, shocked to realize that their creation has suddenly become sentient, try to shut it down. But they are too late. In self-defense, Skynet decides that the only way to protect itself is to destroy humanity by launching a devastating nuclear war. Three billion people are soon incinerated in countless nuclear infernos. In the aftermath, Skynet unleashes legion after legion of robotic killing machines to slaughter the remaining stragglers. Modern civilization crumbles, reduced to tiny, pathetic bands of misfits and rebels. movie series, the Pentagon proudly unveils Skynet, a sprawling, foolproof computer network designed to faithfully control the U.S. nuclear a.r.s.enal. It flawlessly carries out its tasks until one day in 1995, when something unexpected happens. Skynet becomes conscious. Skynet's human handlers, shocked to realize that their creation has suddenly become sentient, try to shut it down. But they are too late. In self-defense, Skynet decides that the only way to protect itself is to destroy humanity by launching a devastating nuclear war. Three billion people are soon incinerated in countless nuclear infernos. In the aftermath, Skynet unleashes legion after legion of robotic killing machines to slaughter the remaining stragglers. Modern civilization crumbles, reduced to tiny, pathetic bands of misfits and rebels.

Worse, in the Matrix Trilogy, Matrix Trilogy, humans are so primitive that they don't even realize that the machines have already taken over. Humans carry out their daily affairs, thinking everything is normal, oblivious to the fact that they are actually living in pods. Their world is a virtual reality simulation run by the robot masters. Human "existence" is only a software program, running inside a large computer, that is being fed into the brains of humans living in these pods. The only reason the machines even bother to have humans around is to use them as batteries. humans are so primitive that they don't even realize that the machines have already taken over. Humans carry out their daily affairs, thinking everything is normal, oblivious to the fact that they are actually living in pods. Their world is a virtual reality simulation run by the robot masters. Human "existence" is only a software program, running inside a large computer, that is being fed into the brains of humans living in these pods. The only reason the machines even bother to have humans around is to use them as batteries.

Hollywood, of course, makes its living by scaring the pants off its audience. But it does raise a legitimate scientific question: What happens when robots finally become as smart as us? What happens when robots wake up and become conscious? Scientists vigorously debate the question: not if, but when this momentous event will happen.

According to some experts, our robot creations will gradually rise up the evolutionary tree. Today, they are as smart as c.o.c.kroaches. In the future, they will be as smart as mice, rabbits, dogs and cats, monkeys, and then they will rival humans. It may take decades to slowly climb this path, but they believe that it is only a matter of time before the machines exceed us in intelligence.

AI researchers are split on the question of when this might happen. Some say that within twenty years robots will approach the intelligence of the human brain and then leave us in the dust. In 1993, Vernor Vinge said, "Within thirty years, we will have the technological means to create superhuman intelligence. Shortly after, the human era will be ended.... I'll be surprised if this event occurs before 2005 or after 2030."

On the other hand, Douglas Hofstadter, author of G.o.del, Escher, Bach, G.o.del, Escher, Bach, says, "I'd be very surprised if anything remotely like this happened in the next 100 years to 200 years." says, "I'd be very surprised if anything remotely like this happened in the next 100 years to 200 years."

When I talked to Marvin Minsky of MIT, one of the founding figures in the history of AI, he was careful to tell me that he places no timetable on when this event will happen. He believes the day will come but s.h.i.+es away from being the oracle and predicting the precise date. (Being the grand old man of AI, a field he helped to create almost from scratch, perhaps he has seen too many predictions fail and create a backlash.) A large part of the problem with these scenarios is that there is no universal consensus as to the meaning of the word consciousness. consciousness. Philosophers and mathematicians have grappled with the word for centuries, and have nothing to show for it. Seventeenth-century thinker Gottfried Leibniz, inventor of calculus, once wrote, "If you could blow the brain up to the size of a mill and walk about inside, you would not find consciousness." Philosopher David Chalmers has even catalogued almost 20,000 papers written on the subject, with no consensus whatsoever. Philosophers and mathematicians have grappled with the word for centuries, and have nothing to show for it. Seventeenth-century thinker Gottfried Leibniz, inventor of calculus, once wrote, "If you could blow the brain up to the size of a mill and walk about inside, you would not find consciousness." Philosopher David Chalmers has even catalogued almost 20,000 papers written on the subject, with no consensus whatsoever.

Nowhere in science have so many devoted so much to create so little.

Consciousness, unfortunately, is a buzzword that means different things to different people. Sadly, there is no universally accepted definition of the term. unfortunately, is a buzzword that means different things to different people. Sadly, there is no universally accepted definition of the term.

I personally think that one of the problems has been the failure to clearly define consciousness and then a failure to quantify it.

But if I were to venture a guess, I would theorize that consciousness consists of at least three basic components: 1.sensing and recognizing the environment 2.self-awareness 3.planning for the future by setting goals and plans, that is, simulating the future and plotting strategy

In this approach, even simple machines and insects have some form of consciousness, which can be ranked numerically on a scale of 1 to 10. There is a continuum of consciousness, which can be quantified. A hammer cannot sense its environment, so it would have a 0 rating on this scale. But a thermostat can. The essence of a thermostat is that it can sense the temperature of the environment and act on it by changing it, so it would have a ranking of 1. Hence, machines with feedback mechanisms have a primitive form of consciousness. Worms also have this ability. They can sense the presence of food, mates, and danger and act on this information, but can do little else. Insects, which can detect more than one parameter (such as sight, sound, smells, pressure, etc.), would have a higher numerical rank, perhaps a 2 or 3.

The highest form of this sensing would be the ability to recognize and understand objects in the environment. Humans can immediately size up their environment and act accordingly and hence rate high on this scale. However, this is where robots score badly. Pattern recognition, as we have seen, is one of the princ.i.p.al roadblocks to artificial intelligence. Robots can sense their environments much better than humans, but they do not understand or recognize what they see. On this scale of consciousness, robots score near the bottom, near the insects, due to their lack of pattern recognition.

The next-higher level of consciousness involves self-awareness. If you place a mirror next to most male animals, they will immediately react aggressively, even attacking the mirror. The image causes the animal to defend its territory. Many animals lack awareness of who they are. But monkeys, elephants, dolphins, and some birds quickly realize that the image in the mirror represents themselves and they cease to attack it. Humans would rank near the top on this scale, since they have a highly developed sense of who they are in relation to other animals, other humans, and the world. In addition, humans are so aware of themselves that they can talk silently to themselves, so they can evaluate a situation by thinking.

Third, animals can be ranked by their ability to formulate plans for the future. Insects, to the best of our knowledge, do not set elaborate goals for the future. Instead, for the most part, they react to immediate situations on a moment-to-moment basis, relying on instinct and cues from the immediate environment.

In this sense, predators are more conscious than prey. Predators have to plan ahead, by searching for places to hide, by planning to ambush, by stalking, by antic.i.p.ating the flight of the prey. Prey, however, only have to run, so they rank lower on this scale.

Furthermore, primates can improvise as they make plans for the immediate future. If they are shown a banana that is just out of reach, then they might devise strategies to grab that banana, such as using a stick. So, when faced with a specific goal (grabbing food), primates will make plans into the immediate future to achieve that goal.