The excited Von Neumann ignored him. He shouted orders at the three soldiers. "Begin operation! Input 1 and Input 2, you can raise whichever flag you want. Good. Raise! Good. Raise again! Raise!"

Input 1 and Input 2 raised their flags three times. The first time they were black-black, the second time white-black, and the third time black-white. Output reacted correctly each time, raising the black flag once and the white one twice.

"Very good. Your Imperial Majesty, your soldiers are very smart."

"Even an idiot would be capable of that. Tell me, what are they really doing?" Qin Shi Huang looked baffled.

"The three soldiers form a computing component. It's a type of gate, an AND gate." Von Neumann paused to let the emperor digest this information.

Qin Shi Huang said impa.s.sively, "I'm not impressed. Continue."

Von Neumann turned to the three soldiers again. "Let's form another component. You, Output: if you see either Input 1 or Input 2 raise a black flag, you raise the black flag. There are three situations where that will be true: black-black, white-black, black-white. When it's white-white, you raise the white flag. Understand? Good lad, you're really clever. You're the key to the correct functioning of the gate. Work hard, and the emperor will reward you! Let's begin operation. Raise! Good, raise again! Raise again! Perfect. Your Imperial Majesty, this component is called an OR gate."

Then, Von Neumann used the three soldiers to form a NAND gate, a NOR gate, an XOR-gate, an XNOR-gate, and a tristate gate. Finally, using only two soldiers, he made the simplest gate, a NOT gate, or an inverter: Output always raised the flag that was opposite in color from the one raised by Input.

Von Neumann bowed to the emperor. "Now, Your Imperial Majesty, all the gate components have been demonstrated. Aren't they simple? Any three soldiers can master the skills after one hour of training."

"Don't they need to learn more?" Qin Shi Huang asked.

"No. We can form ten million of these gates, and then put the components together into a system. This system will then be able to carry out the calculations we need and work out those differential equations for predicting the suns' movements. We could call the system ... um..."

"A computer," w.a.n.g said.

"Ah, good!" Von Neumann gave w.a.n.g a thumbs-up. "Computer-that's a great name. The entire system is a large machine, the most complex machine in the history of the world."

The pa.s.sage of in-game time sped up. Three months went by.

Qin Shi Huang, Newton, Von Neumann, and w.a.n.g all stood on the platform at the apex of the pyramid. This platform was similar to the one where w.a.n.g had met Mozi. It was filled with astronomical instruments, some of which were of recent European design. Below them, a magnificent phalanx of thirty million Qin soldiers was arrayed on the ground. The entire formation fit inside a square six kilometers on each side. As the sun rose, the phalanx remained still like a giant carpet made of thirty million terra-cotta warriors. But when a flock of birds wandered above the phalanx, the birds immediately felt the potential for death from below and scattered anxiously in chaos.

w.a.n.g performed some computations in his head and realized that even if the entire population of Earth were arranged into such a phalanx, the whole formation would fit inside the Huangpu District of Shanghai. Though it was powerful, the phalanx also revealed the fragility of civilization.

Von Neumann said, "Your Imperial Majesty, your army is truly matchless. In an extremely short time, we have completed such complex training."

Qin Shi Huang held on to the hilt of his long sword. "Even though the whole is complex, what each soldier must do is very simple. Compared to the training they went through to learn how to break the Macedonian Phalanx, this is nothing."

Newton added, "And G.o.d blessed us with two consecutive Stable Eras to get them trained and ready."

"Even in a Chaotic Era, my army continues to train. They will finish your calculations even if it's a Chaotic Era." Qin Shi Huang glanced over the phalanx with pride in his eyes.

"Then, Your Imperial Majesty, please give the great order!" Von Neumann's voice trembled with excitement.

Qin Shi Huang nodded. A guard ran over, grabbed the hilt of the emperor's sword, and stepped backwards. The bronze sword was so long that it was impossible for the emperor himself to pull it out of the scabbard. The guard knelt and handed the sword to the emperor. Qin Shi Huang lifted the sword to the sky, and shouted: "Computer Formation!"

Four giant bronze cauldrons at the corners of the platform came to life simultaneously with roaring flames. A group of soldiers standing on the sloping side of the pyramid facing the phalanx chanted in unison: "Computer Formation!"

On the ground below, colors in the phalanx began to shift and move. Complicated and detailed circuit patterns appeared and gradually filled the entire formation. Ten minutes later, the army had made a thirty-six kilometer square computer motherboard.

Von Neumann pointed to the gigantic human circuit below the pyramid and began to explain, "Your Imperial Majesty, we have named this computer Qin I. Look, there in the center is the CPU, the core computing component, formed from your five best divisions. By referencing this diagram, you can locate the adders, registers, and stack memory. The part around it that looks highly regular is the memory. When we built that part, we found that we didn't have enough soldiers. But luckily, the work done by the elements in this component is the simplest, so we trained each soldier to hold more colored flags. Each man can now complete the work that initially required twenty men. This allowed us to increase the memory capacity to meet the minimum requirements for running the Qin 1.0 operating system. Observe also the open pa.s.sage that runs through the entire formation, and the light cavalry waiting for orders in that pa.s.sage: That's the system bus, responsible for transmitting information between the components of the whole system.

"The bus architecture is a great invention. New plug-in components, which can be made from up to ten divisions, can quickly be added to the main operation bus. This allows Qin I's hardware to be easily expanded and upgraded. Look further still-you might have to use the telescope for this-and there's the external storage, which we call the 'hard drive' at Copernicus's suggestion. It's formed by three million soldiers with more education than most. When you buried all those scholars alive after you unified China, it's a good thing you saved these ones! Each of them holds a pen and a notepad, and they're responsible for recording the results of the calculations. Of course, the bulk of their work is to act as virtual memory and store intermediate calculation results. They're the bottleneck for the speed of computation. And, finally, the part that's closest to us is the display. It's capable of showing us in real time the most important parameters of the computation."

Von Neumann and Newton carried over a large scroll, tall as a man, and spread it open before Qin Shi Huang. When they reached the scroll's end, w.a.n.g's chest tightened, remembering the legend of the a.s.sa.s.sin who hid a dagger in a map scroll that he then displayed to the emperor. But the imaginary dagger did not appear. Before them was only a large sheet of paper filled with symbols, each the size of a fly's head. Packed so densely, the symbols were as dazzling to behold as the computer formation on the ground below.

"Your Imperial Majesty, this is the Qin 1.0 operating system we developed. The software for doing the calculations will run on top of it. That below"-Von Neumann pointed to the human-formation computer-"is the hardware. What's on this paper is the software. The relationship between hardware and software is like that between the guqin zither and sheet music."

He and Newton then spread open another scroll, just as large. "Your Imperial Majesty, this is the software for using numerical methods to solve those differential equations. After entering the motion vectors of the three suns at a particular moment obtained by astronomical observation, the software's operation will give us a prediction for the suns' subsequent motion at any moment in the future. Our first computation will calculate all the suns' positions for the next two years. Each set of output values will be one hundred and twenty hours apart."

Qin Shi Huang nodded. "Good. Begin."

Von Neumann lifted both hands above his head and solemnly chanted: "As ordered by the great emperor, turn on the computer! System self-test!"

A row of soldiers standing halfway down the face of the pyramid repeated the order using flag signals. In a moment, the motherboard made of thirty million men seemed to turn into a lake filled with sparkling lights. Tens of millions of tiny flags waved. In the display formation closest to the base of the pyramid, a progress bar made of numerous green flags slowly advanced, indicating the percentage of the self-test that had been completed. Ten minutes later, the progress bar reached its end.

"Self-test complete! Begin boot sequence! Load operating system!"

Below, the light cavalry on the main bus that pa.s.sed through the entire human-formation computer began to move swiftly. The main bus soon turned into a turbulent river. Along the way, the river fed into numerous thin tributaries, infiltrating all the modular subformations. Soon, the ripple of black and white flags coalesced into surging waves that filled the entire motherboard. The central CPU area was the most tumultuous, like gunpowder on fire.

But suddenly, as though the powder had been exhausted, the movements in the CPU slackened and eventually stopped. Starting with the CPU in the center, the stillness spread in every direction, like a sea being frozen over. Finally, the entire motherboard came to a stop, with only a few scattered components flashing lifelessly in infinite loops. The center of the display formation blinked red.

"System lockup!" a signal officer called out. Shortly after, the reason for the malfunction was determined: There was an error with the operation of one of the gates in the CPU status register.

"Restart system!" Von Neumann ordered confidently.

"Wait!" Newton stopped the signal officer. He turned with an insidious expression and said to Qin Shi Huang, "Your Imperial Majesty, in order to improve system stability, you should take certain maintenance measures with respect to faulty components."

Qin Shi Huang grasped his sword and said, "Replace the malfunctioning component and behead all the soldiers who made up that gate. In the future, any malfunctions will be dealt with the same way!"

Von Neumann glanced at Newton, disgusted. They watched as a few riders dashed into the motherboard with their swords unsheathed. After they "repaired" the faulty component, the order to restart was given. This time, the operation went very smoothly. Twenty minutes later, Three Body's Von Neumann architecture human-formation computer had begun full operations under the Qin 1.0 operating system.

"Run solar orbit computation software 'Three Body 1.0'!" Newton screamed at the top of his lungs. "Start the master computing module! Load the differential calculus module! Load the finite element a.n.a.lysis module! Load the spectral method module! Enter initial condition parameters ... and begin calculation!"

The motherboard sparkled as the display formation flashed with indicators in every color. The human-formation computer began the long computation.

"This is really interesting," Qin Shi Huang said, pointing to the spectacular sight. "Each individual's behavior is so simple, yet together, they can produce such a complex, great whole! Europeans criticize me for my tyrannical rule, claiming that I suppress creativity. But in reality, a large number of men yoked by severe discipline can also produce great wisdom when bound together as one."

"Great First Emperor, this is just the mechanical operation of a machine, not wisdom. Each of these lowly individuals is just a zero. Only when someone like you is added to the front as a one can the whole have any meaning." Newton's smile was ingratiating.

"Disgusting philosophy!" Von Neumann said as he glanced at Newton. "If, in the end, the results computed in accordance with your theory and mathematical model don't match reality, then you and I aren't even zeroes."

"Indeed. If that turns out to be the case, you will be nothing!" Qin Shi Huang turned and left the scene.

Time pa.s.sed quickly. The human-formation computer operated for a year and four months. Subtracting out the time spent to adjust the programming, the actual processing time was approximately a year and two months. During this time, processing had to be stopped twice due to extremely bad weather in Chaotic Eras. But the computer stored the data at the time of each shutdown, and was able to resume calculations successfully after the pauses. By the time Qin Shi Huang and the European scholars ascended the pyramid again, the first phase of the computation was complete. The results precisely described the orbits of the three suns for the next two years.

It was a chilly dawn. The torches that had kept the motherboard lit through the night were extinguished. After the final calculation, Qin I entered standby mode. The turbulent waves over the motherboard settled into light ripples.

Von Neumann and Newton presented the scroll with the results of the computation to Qin Shi Huang. Newton said, "Great First Emperor, the calculations were completed three days ago. We waited until now to present the results to you because they show that the long night is about to be over. We'll soon welcome the first sunrise of a long Stable Era, which will last more than a year. Judging by the orbital parameters, the climate will be extremely mild and comfortable. Please revive your empire and order everyone to be rehydrated."

"Ever since the start of this computation, my empire has never been dehydrated," Qin Shi Huang said in a huff, grabbing the scroll. "I've devoted all the resources of the Qin Empire to maintain the operation of the computer, and we've run out of stored supplies. For this computer, countless people have died of hunger, cold, and heat." Qin pointed into the distance with the scroll. By the dim dawn light, they could see tens of white lines radiating from the edges of the motherboard in every direction, disappearing over the horizon. These were the supply routes from every corner of the empire.

"Your Imperial Majesty, you will find that the sacrifices are worth it," Von Neumann said. "After mastering the orbits of the suns, Qin will develop by leaps and bounds, and will grow many times more powerful than before."

"According to the calculations, the sun is about to rise. Great First Emperor, prepare to receive your glory!"

As if in response to Newton's words, a sliver of red sun peeked over the horizon, bathing the pyramid and the human-formation computer in a golden light. A wave of joyous cries rose from the motherboard.

A man hurried toward them. He was running so fast that, as he knelt down, he couldn't catch his breath. He was the emperor's astronomy minister.

"Sire, the calculations were in error. Disaster is about to befall us!"

"What are you babbling about?" Without even waiting for the emperor to speak, Newton kicked the man. "Don't you see that the sun is rising at the exact moment predicted by our precise calculations?"

"But..." The minister half straightened, one hand pointing at the sun. "How many suns do you see?"

Everyone gazed at the rising sun, confused. "Minister, you received a proper Western education and obtained a doctorate from the University of Cambridge," Von Neumann said. "You must at least know how to count. Of course there's only one sun in the sky. And the temperature is very comfortable."

"No. There are three!" The minister cried, tears flowing from his face. "The other two are behind that one!"

Everyone stared at the sun again, still confused.

"The Imperial Observatory has confirmed that right now we are experiencing the extremely rare phenomenon of a tri-solar syzygy. The three suns are in a straight line, moving around our planet at the same angular speed! Thus, our planet and the three suns are in a straight line with our world at the end!"

"You're certain that the observation is not in error?" Newton grabbed the collar of the astronomy minister.

"Absolutely certain. The observation was conducted by the Western astronomers of the Imperial Observatory, including Kepler and Herschel. They're using the largest telescope in the world, imported from Europe."

Newton let go of the minister and stood up. w.a.n.g saw that his face was pale, but his expression was one of pure joy. He clasped his two hands in front of his chest and said to Qin Shi Huang, "Oh Greatest, Most Honorable Emperor, this is the most propitious sign of them all! Now that the three suns are orbiting around our planet, your empire is the center of the universe. This is G.o.d's reward for our efforts. Let me check the calculations one more time. I will prove this!"

While the rest remained stunned, Newton slipped away. Later, others would report that Sir Isaac had stolen a horse and left for parts unknown.

An anxiety-filled moment of silence later, w.a.n.g suddenly said, "Your Imperial Majesty, please unsheathe your sword."

"What do you want?" Qin Shi Huang asked, baffled. But he gestured at the soldier by his side, and the soldier pulled the sword out of its scabbard.

w.a.n.g said, "Please try to swing it."

Qin Shi Huang held the sword and waved it around. His expression turned to one of surprise. "Oh, why is it so light?"

"The game's V-suit cannot simulate the feeling of diminished gravity. Otherwise we'd feel that we're much lighter as well."

"Look! Down there! Look at the horses, and the men!" Someone cried out. Everyone looked down and saw a column of cavalry moving at the foot of the pyramid. All the horses seemed to be floating. Each horse drifted over a long distance before the four hooves struck ground again. They also saw several running men. With each step, the men leapt a dozen meters, falling slowly back to the ground. On top of the pyramid, a soldier tried to jump up, and easily reached the height of three meters.

"What is going on?" Qin Shi Huang looked at the soldier slowly falling back down.

"Sire, the three suns are over our planet in a straight line, so their gravitational forces are added together...." The astronomy minister tried to explain, but discovered that his two feet had already left the ground and he was now horizontal. The others were also floating in the air, leaning at different angles. Like a bunch of men who had fallen into water without knowing how to swim, they clumsily waved their limbs, trying to stabilize themselves but colliding into each other instead.

The ground they had just left now cracked open like a spiderweb. The cracks grew fast, and, accompanied by thunderous crashes and sky-obscuring dust, the pyramid below them broke into its const.i.tuent blocks. Through the slowly drifting gigantic blocks, w.a.n.g saw the Great Hall below come apart. The large cauldron that had once cooked Fu Xi and the iron stake to which he had once been bound were both adrift.

The sun rose to the middle of the sky. Everything that floated-men, colossal blocks of stone, astronomical instruments, bronze cauldrons-began to rise slowly, then accelerated. w.a.n.g glanced at the human-formation computer and saw a nightmarish sight: The thirty million men who had formed the motherboard were floating away from the earth and rising, like a swarm of ants sucked up by a vacuum cleaner. The ground they left behind clearly displayed the marks of the motherboard circuits. The set of intricate, complex markings that could only be taken in from a great height would become an archaeological site that would confuse the next Three Body civilization, in the distant future.

w.a.n.g looked up. The sky was obscured by a strangely mottled layer of clouds. The clouds were made of dust, stones, humans, and other odds and ends. The sun sparkled behind them. In the far distance, w.a.n.g saw a long range of transparent mountains also rising up. The mountains were crystal clear, and changed shapes as they sparkled-they were formed from the ocean, which was also being attracted into s.p.a.ce.

Everything on the surface of the Three Body world rose toward the sun.

w.a.n.g looked around and saw Von Neumann and Qin Shi Huang. As he drifted, Von Neumann shouted at Qin Shi Huang, but there was no sound. A small set of subt.i.tles appeared: I figured it out! Electronic elements! We can use electronic elements to make gate circuits and combine them into computers! Such computers will be many times faster and take up much less s.p.a.ce. I estimate that a small building will be sufficient.... Your Imperial Majesty, are you listening?

Qin Shi Huang swung his long sword at Von Neumann. The latter kicked at a giant block of stone drifting nearby and dodged out of the way. The long sword struck the stone, causing sparks to fly, and broke itself into two pieces. Right after, the giant block of stone collided with another, with Qin Shi Huang in the middle. Stone chips and flesh and blood scattered everywhere, an appalling sight.

But w.a.n.g did not hear the noise made by colliding stones. Around him it was completely silent. Because the atmosphere was gone, there was no more sound. As the bodies drifted, their blood boiled in the vacuum and their inner organs were vomited out, until they turned into strange blobs surrounded by crystalline clouds made from the liquid they exuded. Also, due to the lack of an atmosphere, the sky turned pitch black. Everything that had floated into s.p.a.ce from the Three Body world reflected the sunlight and formed a brilliant, starry cloud in s.p.a.ce. The cloud then turned into a giant vortex, spiraling toward its final resting place: the sun.

w.a.n.g now saw the sun changing shape. He understood that he was actually seeing the other two suns, both peeking out from behind the first sun. From this perspective, the three stacked suns formed a bright eye in the universe.

Against the background of the three suns in syzygy, text appeared: Civilization Number 184 was destroyed by the stacked gravitational attractions of a tri-solar syzygy. This civilization had advanced to the Scientific Revolution and the Industrial Revolution.

In this civilization, Newton established nonrelativistic cla.s.sical mechanics. At the same time, due to the invention of calculus and the Von Neumann architecture computer, the foundation was set for the quant.i.tative mathematical a.n.a.lysis of the motion of three bodies.

After a long time, life and civilization will begin once more, and progress through the unpredictable world of Three Body.

We invite you to log on again.

Just as w.a.n.g logged out of the game, a stranger called. The voice on the phone was that of a very charismatic man. "h.e.l.lo! First, we thank you for giving us your real number. I'm a system administrator for the Three Body game."

w.a.n.g was both excited and anxious.

"Please tell us your age, education, employer, and position. You didn't fill those out when you registered."

"What do they have to do with the game?"

"When you've reached this level, you must provide these pieces of information. If you refuse, Three Body will be permanently closed to you."

w.a.n.g answered the administrator's questions truthfully.

"Very good, Professor w.a.n.g. You satisfy the conditions for continuing in Three Body."

"Thank you. Can I ask you a few questions?"

"You may not. But tomorrow night there will be a meet-up for Three Body players. We welcome you to attend." The administrator gave w.a.n.g an address.

18.