"Then can you tell me something about the justice of this universe?" "Ok, come with me." Luo Ji said, and went straight to the depths of the desert, mahavamsa behind him. They walked a long way in silence on the expressway.

"Where are we going?" Shi Qiang asked.

"Go to the darkest place."

Two people walked to the other side of the road, where the roadbed blocked the lights of the residential area, surrounded by darkness, Luigi and Shi Qiang groped and sat in the sand.

"Let's get started." Luo Ji's voice rang out in the darkness.

"You speak more popular. My cultural level is complicated and I can't understand it. "

"Can understand, mahavamsa, the reason is very simple, it is this kind of thing, let you hear it and wonder why you can't find it. Do you know the axiom in mathematics? " "I studied geometry in middle school, that is, I can only draw after two o'clock, the obvious thing of line."

"Yes, now we have to find two axioms for cosmic civilization: first, survival is the first need of civilization. Second, civilization continues to grow and develop, but the total address of matter in the universe remains unchanged. "

"What else?" "Not anymore."

"What can be inferred from such a small matter?" "Mahavamsa, you can restore the whole case from a warhead or a drop of blood. Cosmic sociology is to describe the whole picture of galactic civilization and cosmic civilization from these two axioms. Science is like this, and the cornerstone of each system is very simple. "

"Then why don't you deduce it?" "First of all, let's talk about the dark war. If I say that the starship earth is the epitome of cosmic civilization, do you believe it? " "No, starship earth lacks resources such as bidding materials and accessories, but the universe is not lacking. The universe is too big. "

"You are wrong, the universe is big, but life is bigger! This is what the second axiom shows. The total amount of matter in the universe is basically the same, but life is growing exponentially! Exponent is the devil in mathematics. If there is an invisible bacterium in the sea, it will divide every half hour. As long as there is enough nutrition, its descendants can fill all the oceans on the earth in a few days. Don't let humans and the three-body world give you the illusion. Both civilizations are small, but they are only in the infant stage of civilization. As long as the technology mastered by civilization exceeds a certain threshold, the expansion of life in the universe is terrible. For example, at the current speed of human navigation, in another million years, the earth civilization will fill the entire galaxy. One million years, according to the scale of the universe, is only a short time. " "you mean, in the long run, the whole universe may appear like the starship earth ... what do they say, to be or not to be?" "Don't in the long run, now the nuclear universe is a life-and-death situation! As Shane said, civilization probably sprouted in the universe billions of years ago. Judging from the current signs, the universe may already be crowded. No one knows how many empty places and unoccupied resources there are in the Milky Way and the whole universe. " (1) "is this wrong? The universe looks empty. I didn't see any other alien life except the three-body? " "This is what we want to say next. Give me a cigarette. " Luo Ji groped along while, just took the cigarette from the hand of the stone. When he heard Luigi speak again, Shi Qiang found that he was sitting three or four meters away from himself. "We must keep our distance to feel more like space." Luo Ji said, then he twisted the filter part of the cigarette to make it tender. At the same time, Shi Qiang also lit a cigarette. In the darkness, two small Mars are far apart.

"Well, in order to illustrate the problem, now we need to build a most concise model of cosmic civilization: these two Mars represent two civilized planets, and the whole universe is only composed of these two planets, and there is nothing else. You delete everything around you. How to find this feeling ① Birds occupy different resources among civilizations with different life attributes, so the resource allocation of civilizations in the universe may be divided into many parallel levels, from broken life to silicon-based life to compassion! The mysterious resources of life and electric life basically contain all the material forms in the universe, and most of the resources involved in each layer do not interfere with each other, but they also re-enter. Really? " "Well, it feels easier to find it in this dark place."

"Now we call these two civilized worlds yours and mine respectively. The two worlds are far apart, even if it is a hundred light years. You detected my existence, but you don't know more details, and I don't know your existence. "

"hmm."

"There are two concepts that need to be defined: goodwill and malice between civilizations. Words such as good and evil are not rigorous in science, so their meanings need to be limited: goodwill means not actively attacking and destroying other civilizations, while malice is the opposite. "

"Is this the minimum kindness?" "You already know the existence of my civilization in the universe. Please consider your choice for me. Please note that in this process, we must always keep in mind the axioms of cosmic civilization and must always consider the environment and distance scale in space. "

"I choose to communicate with you?" "If you do this, you should pay attention to the price you pay: you expose your existence."

"Yes, this is not a trivial matter in the universe."

"There are various degrees of exposure: the strongest exposure is to let me know your precise coordinates in interstellar space, and the second is to let me know your general direction. The weakest exposure only lets me know your existence in the universe. But even the slightest exposure may make me search and find you. Since you can detect my existence, of course I may find you. From the perspective of technological development, it is only a matter of time. "

"But bro, I can take the risk to communicate with you. If you are malicious, it's my bad luck. If you are kind, then we can further communicate and finally unite into a greater goodwill civilization. "

"Well, mahavamsa, let's get down to business. Let's go back to the axiom of cosmic civilization: even if I am a well-intentioned civilization, can I judge that you are well-intentioned at the beginning of communication? " "Of course not, this is in violation of article 1? Axiom: "So, what should I do after I receive your AC signal?" "Of course, you have to judge whether I am kind or malicious. If it is malicious, you will destroy me; If it is goodwill, we will continue to communicate. " Mars rises beside Luo Ji and moves back and forth. Obviously, he stood up and paced. "Can be on the earth, not in the universe. Here we introduce an important concept: the chain of doubt J. ""A rather strange word. "

"I only got such a word at first, and she didn't explain it, but I finally deduced its meaning literally."

"What? Who is he? " "... let's talk about it later. Let's continue: if you think I am kind, that's not why you feel safe, because according to the first axiom, a kind civilization can't think of other civilizations as kind in advance, so you don't know what I think of you, and you don't know whether I think you are kind or malicious; Furthermore, even if you know that I imagine you as kind, I know that you imagine me as kind, but I don't know what you think of me. What you think of me is quite roundabout, isn't it? This is the third level, and this logic can go on forever. "

"I see what you mean."

"This is the chain of doubt, this kind of thing is invisible on the earth. Humans have the same species, similar cultures, interdependent ecosystems and close distances. In such an environment, the chain of suspicion can only extend for one or two layers, which will be dispelled by communication. But in space, the chain of doubt may extend very long. Before it was dispersed by communication, something like a dark war had already happened. "

The maharaja took a puff at his cigarette and his thoughtful face appeared in the darkness. "Now it seems that dark warfare can really teach us a lot."

"Yes, the five ships of Starship Earth are only five' cosmic civilizations', which are not real cosmic civilizations-because they are all made up of the same species of human beings, and the distance between them is also very close-even so, in do or die, the chain of suspicion still appears. In the real cosmic civilization, the biological differences between different races may reach the door or even the border level, and the cultural differences are even more unimaginable, separated by incomparable distances. The chain of suspicion between them is almost indestructible. "

"That is to say, whether you and I are a well-meaning civilization or a malicious civilization, the result is the same?" "Yes, this is the most important feature of the chain of suspicion: it has nothing to do with the social form and moral orientation of civilization itself. Think of each civilization as a point at both ends of the chain. Whether it is good or bad inside, it will become the same thing after entering the network formed by the chain of suspicion. "

"But if you are much weaker than me, there is no threat to me, so I can always communicate with you?" "No, this will lead to the second important concept: technological explosion. She doesn't have time to explain the concept, but it's much easier to speculate than the chain of suspicion. Human civilization has a history of 5000 years, and the life history of the earth has several billion years. However, modern technology has developed for 300 years. From the time scale of the universe, this is not development at all, but explosion! The possibility of technological leap is the explosive buried in every civilization. If it is softened by internal or external factors, it will explode with a bang! The earth is a hundred years old, but there is no reason to think that human beings are the fastest growing civilizations in the universe, and the technological explosion of other civilizations may be more rapid. I am weaker than you. I didn't know you existed until I received your communication information, and the chain of suspicion between us was established. During this period, I may have a technical explosion at any time, and I will walk far ahead of you at once and become stronger than you. You know, on the scale of the universe, hundreds of years is just a flick of a finger, and I know that your existence and the information you get from communication are probably the best fuse for technological explosion. Therefore, even if I am just a baby civilization, or a civilization that has just sprouted, it is full of danger for you. "

Shi Qiang looked at Mars in the dark in the distance and pondered for a few seconds. Then he looked at himself. In biology, biological classification is divided into boundaries, phyla, class, order, family and species. The lower the class, the more similar the squid. The biological differences between human races on the earth are also limited to the species level. If we consider the existence of J-Ming non-basic creatures, it is transcendence! Worldwide, racial differences may not be limited to cigarette butts. "Well, I can only keep silent."

"Do you think this is right?" They are all smoking. As Mars lights up from time to time, two faces appear alternately in the darkness, as if they were two thoughtful gods in this simple universe.

Shi Qiang said: "No, if you are better than me, since I can find you, then one day you can search for me, so there will be a series of doubts between us." If you are weaker than me, but there may be a technical explosion at any time, it will become the first situation. To sum up: first, let you know my existence; It is dangerous for me to let you exist, which violates the first axiom j Mahayana, you are really a clear-headed person. "

"At first, my brain could still talk to you."

Luo Ji was silent for a long time in the dark. His face appeared two or three times in the twilight of Mars before he said, "Mahayana is not the beginning, our inference is over." "end? We got nothing. What about the picture of cosmic civilization you said? " "After learning of my existence, you can't communicate or be silent. You only have one choice."

In the long silence, both Mars went out and there was no wind. In silence, the darkness becomes as thick as asphalt, and the night sky sticks to the desert. Finally, Shi Qiang only said one word in the dark: Fuck! ""Extrapolate your choice to hundreds of millions of civilizations among hundreds of billions of stars, and the overall situation will come out. " Luo Ji nodded in the dark and said.

"This ... is too dark ..."

"The real universe is so dark." Luo Ji reached out and waved, feeling the dark texture that felt like velvet. "The universe is a dark forest. Every civilization is a hunter with a gun, sneaking in the forest like a ghost, gently pushing the branches in the way, trying not to make a sound, even breathing carefully ... He must be careful, because there are hunters sneaking around like him everywhere in the forest. If he finds other life, whether it's a hunter, an angel or a devil, a delicate baby, an old man walking like a mountain, a girl like a fairy, or a teenager like a god, there is only one thing he can do: shoot it. In this forest, others are hell and an eternal threat, and any life that exposes its existence will soon be destroyed. This is the picture of cosmic civilization, which is the explanation of Fermi paradox. "

Mahavamsa lit another cigarette, just for a little light.

"But in the dark forest, there was a silly boy named Human. He made a fire and shouted: Here I am! I am here! " Luo Ji said.

"Did anyone hear that?" "It will definitely be heard, but it can't judge the child's position. So far, mankind has not sent the exact information of the position of the earth and the solar system to the universe. All we can know from the information we have sent is the relative distance between the solar system and the three-body world and the general direction of these two worlds in the Milky Way, but the exact location of these two worlds is still a secret. You know, we are in the wilderness on the edge of the Milky Way, which is relatively safe. "

"What about your magic?" "I sent the next photo to the universe through the sun. There are thirty points on each picture, representing the projection of thirty stars on the corresponding plane of the three-dimensional coordinate system. Combining this map according to the three-dimensional coordinates of the moon forms a cubic space. Thirty points are distributed in this space, indicating the relative positions of 187J3XI and the surrounding three stars, and at the same time, 187J3XI is indicated by an identifier.

"If you think about it carefully, you will understand that a hunter in the dark forest, while holding his breath, suddenly saw a tree in front of him cut off a piece of bark, revealing striking white wood, and marked a position in the forest with words that all hunters can recognize. What will the hunter think of this position? I certainly don't think anyone else has prepared supplies for him. Among all other possibilities, a very big possibility is to tell everyone that there are live prey to be destroyed. The purpose of marking is not important, what is important is that the nerves in the dark forest have reached the limit in do or die, and the most sensitive nerve is the one that is most easily touched. Suppose there are/kloc-0.0 million hunters in the forest (the number of civilizations among hundreds of billions of stars in the Milky Way may be 1000 times higher), and there may be 900 thousand who ignore this sign; Of the remaining100000 hunters, 90000 may have detected that position and ignored it after confirming that there was no creature. Then among the last remaining 10,000 hunters, someone will definitely make such a choice: shoot at that position as far as possible, because for a civilization with a certain degree of technological development, attack may be more labor-saving and safer than detection. If there is really nothing in that position, there is nothing to lose. Now, this hunter has appeared. "

"You can't cast spells anymore, can you?" "Yes, mahavamsa, never send out. The spell must be broadcast to the whole galaxy, and the sun is blocked. "

"Humans are only one step late?" Shi Qiang threw away the cigarette butt, and the spark drew an arc in the darkness, temporarily illuminating a small circle of sand.

"No, no, think about it. If the sun is not blocked, what will happen if I threaten to cast a spell on it in the three-body world?" "You will be stoned to death by the crowd like Ray Diaz, and then the world will legislate to absolutely forbid others to think about it." "Yes, mahavamsa, because the relative distance between the solar system and the three-body world and the general direction in the Milky Way have been published, which exposes the position of the three-body world almost equivalent to exposing the position of the solar system, which is also a mutually assured destruction strategy. It may be a step late, but it is an impossible step for human beings. "

"You should directly threaten the three bodies."

"It's strange, I was not sure, have to confirm it. There's plenty of time anyway. In fact, the real reason is deep in my heart. I really don't have that kind of spiritual strength, and I don't think others will. "

"Now that I think about it, we shouldn't go to see the mayor today. It's even more hopeless if the whole world knows. Think about the situation of those two swing grass. " "I just want to do my duty. You're right, it's true. I hope we won't tell anyone, but you can say it, as she said: I did my duty anyway. " "Rest assured, bro, I will never say."

"In any case, hope no longer exists."