The Dark Forest

by Liu Cixin

  “From that moment, I knew the real you: a deep-rooted defeatist and a staunch Escapist. Both before and after you became a Wallfacer, your sole goal was to achieve an exodus of humanity. Compared to the other Wallfacers, your genius lay not in strategic deception, but in concealing and disguising your true worldview.

  “But I still didn’t know how you would achieve this goal through your research into the brain and thoughts. I was confused even when the mental seal came out, all the way up until the moment I entered hibernation, when I remembered their eyes. The eyes of those people who had been given the mental stamp … they were like yours. And all of a sudden I understood an expression of yours that I’d never been able to read before. That was when I broke through to your real strategy, but it was too late to say anything.”

  The representative of the North American Fleet said, “Ms. Keiko Yamasuki, I don’t think there’s anything unusual here. We know the history of the mental seal. In the first group of fifty thousand volunteers, the procedure was carried out under the strictest of supervision.”

  “That’s right,” she said. “But the supervision was only absolutely effective so far as the content of the faith proposition was concerned. The mental seal itself was much harder to supervise.”

  “But the literature indicates that the supervision of the technical details of the mental seal was very strict as well, and it underwent a large number of tests before it was put into operation,” the chair said.

  Yamasuki shook her head. “The mental seal is an incredibly complicated piece of equipment. Any supervision will have gaps. Specifically, one tiny minus sign out of hundreds of millions of lines of code. Even the sophons didn’t detect it.”

  “A minus sign?”

  “When the neural circuit model for judging a proposition to be true was discovered, Hines also discovered the model for judging a proposition to be false. That was what he needed. He concealed this discovery from everyone, including me. It wasn’t difficult, because the two models were highly similar. It manifested as the direction of flow of a key signal in the neuron transmission model, and in the mathematical model of the mental seal, it was represented by a sign. Positive for true, negative for false. Working in extreme secrecy, Hines manipulated this sign in the mental seal’s control software. In all five devices, the sign was negative.”

  A deathly silence fell over the auditorium, a silence that had manifested only once before during a PDC Wallfacer Hearing two centuries ago, when Rey Diaz had shown off the “cradle” on his wrist and had told the assembly that the device receiving the anti-trigger signal was nearby.

  “Dr. Hines, what have you done?” The chair turned toward him in anger.

  Hines raised his head, and everyone could see that his pallid face had returned to normal. His voice was calm and even. “I admit that I underestimated the power of humanity. The progress that you’ve made is truly unbelievable. I have seen it, and I believe it, and I also believe that victory in the war belongs to humanity. This faith is as steadfast as if it had been imprinted by the mental stamp. The defeatism and Escapism of two centuries ago is truly ridiculous. However, Mr. Chair and representatives, I would like to say to the world that it is impossible to make me repent of what I have done.”

  “You still think you shouldn’t repent?” the representative of the Asian Fleet demanded angrily.

  Hines raised his head. “It’s not a question of ‘should.’ It’s an impossibility. I used the mental seal to imprint this proposition on myself: Everything about my Wallfacer plan is entirely correct.”

  The assembly exchanged amazed glances, and Yamasuki even turned to her husband with the same expression.

  Hines flashed her a small smile and nodded. “Yes, dear, if you’ll permit me to call you that. Only by doing that could I obtain the spiritual strength necessary to execute the plan. Yes, right now I believe all I’ve done is correct. I absolutely believe it, regardless of what reality says. I used the mental seal to turn myself into my own god, and God can’t repent.”

  “In the not-too-distant future, when the Trisolaran invaders surrender to a more powerful human civilization, will you still think that?” the chair asked, with a look in his eyes that was more curious than amazed.

  Hines nodded earnestly. “I’ll still think that I’m right. Everything about my Wallfacer plan is entirely correct. Of course, in the face of the facts, I’ll be put through a hell of a torture.” He turned to his wife. “Dear, you know I’ve already suffered that torture once, when I believed that water was toxic.”

  “Let’s come back to the present day,” the representative of the North American Fleet said, interrupting everyone’s whispered discussions. “It’s just speculation that the Imprinted have endured. It’s been over one hundred seventy years, after all. If a class or organization with such an absolute faith in defeatism exists, why haven’t there been any signs of it?”

  “There are two possibilities,” the representative of the European Fleet said. “One is that the mental seal vanished long ago, and this is just a false alarm.…”

  The representative of the Asian Fleet completed his thought. “But there’s another possibility: The most frightening thing about the situation is the fact that there aren’t any signs.”

  * * *

  Luo Ji and Shi Qiang walked through the underground city shaded by the tree-shaped structures as streams of cars flew through the gaps in the sky above them. Because the buildings were “leaves” hanging in the air, the ground was wide open, and the widely spaced trunks of the giant trees meant there was no sense of streets, just a rolling plaza dotted with tree trunks. The environment was wonderful: The wide swaths of grasses, forests of actual trees, and fresh air all made it look at first glance like beautiful countryside. Pedestrians passed through in shining clothes like glowing ants. Luo Ji was impressed to no end by the urban design that elevated modern noise and crowdedness into the air and let the ground return to nature. Here, there was no shadow of the war, only human comforts and pleasures.

  Before they had gotten far, he heard a woman’s gentle voice. “Is that Mr. Luo Ji?” He looked around and found that the voice was coming from a billboard on the grass at the side of the road. An attractive woman dressed in a uniform was looking at him from the moving image.

  “I am,” he said with a nod.

  “Hello. I am Financial Counselor 8065 of the General Banking System. Welcome to our era. I will now inform you of your current financial situation.” As she spoke, a table of data appeared beside her. “These are your financial records for Year 9 of the Crisis Era, including deposits at the Industrial and Commercial Bank of China and the China Construction Bank. There are investments in quoted securities as well, but those items may have been partially lost during the Great Ravine.”

  “How does she know I’m here?” he whispered.

  Shi Qiang said, “A chip’s been implanted in your left arm. Don’t worry, these days everyone’s got one. It’s like an ID card. All billboards can recognize you. Ads are all personalized now, so no matter where you go, everything on the billboards is showing just for you.”

  Apparently hearing Shi Qiang’s words, the counselor said, “Sir, this isn’t an advertisement. It’s a service from the General Banking System.”

  “How much do I have on deposit?” Luo Ji asked.

  A highly complicated chart appeared next to the counselor. “This is the status of all your interest-bearing accounts since Year 9 of the Crisis Era. It’s fairly complicated, but you can access it in your personal information area from now on.” Another, simpler chart popped up. “This is your current financial situation in all of the various subsystems of the General Banking System.”

  Luo Ji had no concept of what those figures meant, and asked blankly, “That’s … how much?”

  “My boy, you’re a rich man!” Shi Qiang said, slapping him vigorously. “I may not have as much as you, but I’ve still got money. Heh, two centuries of interest—it’s a real long-term inves
tment. Pauper to tycoon. I only regret not saving a little more.”

  “Well … are you sure there’s nothing wrong?” Luo Ji asked, skeptically.

  “Hmm?” The big eyes of the counselor looked at Luo Ji quizzically.

  “It’s been more than one hundred eighty years. Wasn’t there any inflation? Did the finance system really just continue on smoothly?”

  “You’re overthinking it,” Shi Qiang said, taking a pack of cigarettes out of his pocket. Luo Ji knew then that tobacco was still around. But when Shi Qiang took one out, he was able to puff out clouds of smoke without lighting it.

  The counselor replied, “There were many rounds of inflation during the Great Ravine, and the finance and credit systems came close to collapse. But according to current laws, interest on the deposits of hibernators is calculated according to a special formula that excludes the Great Ravine, and instead transfers the deposit amount over to the financial level of the post-Ravine period and resumes calculating interest from there.”

  “Wow, that’s some preferential treatment!” Luo Ji exclaimed.

  “My boy, these are good times,” Shi Qiang said, blowing out smoke. Then, raising his still-burning cigarette, he said, “Except the cigarettes are terrible.”

  “Mr. Luo Ji, this is just an opportunity for us to get acquainted. When it’s convenient for you, we can discuss your personal financial arrangements and investment plan. If there’s nothing else, then I’ll say good-bye.” The counselor smiled and waved good-bye.

  “I’ve got one question,” he said quickly. He didn’t know what to call young women in this era, and didn’t want to risk making a mistake by addressing her improperly. So he simply said, “I’m not too familiar with this era, so please forgive me if my question is offensive to you.”

  The counselor smiled, and said, “Not a problem. Our responsibility is to help you get acquainted with this era as quickly as possible.”

  “Are you a real person or a robot? Or are you a program?”

  The question didn’t faze the counselor. She replied, “Of course I’m a real person. Could a computer handle services as complicated as this?”

  After the woman on the billboard disappeared, Luo Ji said to Shi Qiang, “Da Shi, there are some things I find hard to understand. This is an age that has invented perpetual motion and can synthesize grain, but computer technology doesn’t seem to have advanced at all. Artificial intelligence can’t even handle personal finance.”

  “What perpetual motion? You mean a perpetual motion machine?” Shi Qiang said.

  “Yeah. It signifies unlimited energy.”

  Shi Qiang looked around him. “Where?”

  Luo Ji pointed up to the stream of traffic. “Those flying cars. Do they consume oil or batteries?”

  Shi Qiang shook his head. “Neither. Earth’s oil was pumped dry. Those cars can fly forever without batteries and they’ll never run out of power. They’re pretty awesome. I’m thinking of getting one myself.”

  “How can you be so unmoved by a technological miracle? Unlimited power for humanity. This is as big an event as when Pangu created the heavens and the Earth! Don’t you realize what a magnificent age this is?”

  Shi Qiang tossed aside the cigarette butt; then, thinking better of it, reached down and retrieved it from the grass and threw it into a nearby garbage can. “I’m unmoved? You’re an intellectual whose imagination has gotten away from him. The technology is something we actually had in our era.”

  “You’ve got to be kidding.”

  “I don’t understand most tech, but I do know a bit about this one thing in particular because, as it happens, I once had occasion to use a police bug that had no batteries but never ran out of power. You know how it worked? It was powered remotely by microwaves. That’s what electricity is today, although the methods are a little different from our day.”

  Luo Ji stopped and stared at Shi Qiang for a long while, then up at the flying cars in the air. He thought about the heating glass, and finally understood: It was just a wireless power supply. The power source emitted electricity in the form of microwaves or other EM radiation to form an electric field over a certain space, allowing any equipment within it to draw power through an antenna or resonant coil. Like Shi Qiang had said, even two centuries ago, this technology was entirely ordinary. The only reason it hadn’t been commonplace was because the power loss was too great. Only a small portion of the power emitted into a space could be used, but the majority was lost. In this era, however, mature controlled fusion technology meant that energy sources had been greatly enriched, to the point that losses from wireless power supplies were acceptable.

  “And the synthetic grain? Can’t they synthesize grain?” Luo Ji asked.

  “I’m not really sure about that. Grain is still grown from seed, it’s just that it’s grown in factories in those cultivation tank things. Crops are all genetically modified, and I’ve heard that wheat grows just an ear, with no stalk. And it grows pretty quickly because of the strong artificial sunlight, and other things like intense, growth-inducing radiation. A season of wheat and rice can be harvested in a week, so from the outside it looks just like it’s produced on a production line.”

  “Oh—” Luo Ji punctuated his thought with an extended sigh as the gorgeous bubbles before his eyes burst to reveal the true face of the world, and he knew that in this great new era, sophons still floated everywhere and human science was still deadlocked. Existing technology could never cross the line set down by the sophons.

  “And the spacecraft that can reach fifteen percent of light speed?”

  “Well, that’s true. When those warships mobilize, it’s like a tiny sun in the sky. And their space weapons—the day before yesterday I saw a news report on TV about an Asian Fleet exercise. A laser cannon swept a target ship as big as a carrier. Half of that iron guy evaporated like a chunk of ice, and the other half exploded like fireworks in a shower of sparkling molten steel. And there are railguns that can fire a hundred iron spheres a second, each the size of a football, at tens of kilometers per second. In a few minutes they can flatten a mountain on Mars.… So even though there isn’t any of your perpetual motion, with these technologies, humanity is more than capable of putting down the Trisolaran Fleet.”

  Shi Qiang handed Luo Ji a cigarette and taught him how to twist the filter tip to light it. They smoked and watched the snow-white swirls drift upward. “Anyway, my boy, these are good times.”

  “Yes. Good times.”

  Luo Ji had hardly finished speaking when Shi Qiang pounced on him and the two of them tumbled onto the grass a few meters away, hearing a loud noise at their heels as a flying car smashed into the spot where they had just been standing. Luo Ji felt the impact of the blast, and metal debris whizzed overhead, taking out half the billboard and sending the transparent glass tubes of the display crashing to the ground. While he was still on the ground with a dizzy head and a black eye, Shi Qiang leapt up and ran over to the flying car. Its disc-shaped body was entirely broken and deformed, but due to the lack of onboard fuel, it hadn’t caught fire. There was only the sound of sparks crackling in the twisted metal.

  “There’s no one in the car,” Shi Qiang said to Luo Ji, who was limping over.

  “Da Shi, you saved my life again,” Luo Ji said, leaning on his shoulder and massaging his injured leg.

  “I don’t know how many times I’ll have to. You really ought to grow some sense, and a few more eyes.” He pointed to the totaled flying car. “Remind you of anything?”

  Luo Ji thought about that occasion two centuries before and shivered involuntarily.

  Lots of pedestrians crowded round, the scenes of terror on their clothing flashing as one. Two police cars landed, sirens blaring, and several officers got out to form a line around the broken car. Their uniforms flashed like the police light, drowning out the crowd’s clothing with their brightness. The one officer who came over to Shi Qiang and Luo Ji had clothing so bright they had to shut their eyes.
/>
  “You were right here when the car fell. You aren’t hurt, are you?” he said with concern. He evidently could see that the two of them were hibernators, because he made an effort to speak “ancient Chinese.”

  Before Luo Ji could answer, Shi Qiang pulled the officer who had asked the question across the tape and out of the crowd. Once they had gotten away, the officer’s uniform stopped flashing.

  “You need to check up on this. It might be an assassination attempt,” he said.

  The officer laughed. “Really? It’s just a traffic accident.”

  “We want to report it.”

  “Are you sure?”

  “Of course. We’re reporting it.”

  “You’re making a big deal out of it. You may have been startled, but it really was a traffic accident. However, according to the law, if you insist on reporting it…”

  “We insist.”

  The officer pressed a display area on his sleeve. It popped up an information window, which he looked over, and then said, “It’s been reported. For the next forty-eight hours, the police will track you, but this requires your agreement.”