黑暗森林

我昨天晚上终于看完了《三体》。看完以后我睡不着，一直在想宇宙的事。你看过这本书吗？

Last night I finally finished The Three-Body Problem. Afterwards I couldn't sleep. I just lay there thinking about the universe. Have you read it?

当然看过，我看的是中文的，三本都看完了。你知道写这本书的作家是做什么的吗？刘慈欣以前是个工程师，白天上班，晚上写科幻小说。

Of course I have. I read it in Chinese, all three books. Do you know what the author did for a living? Liu Cixin used to be an engineer. He went to work in the daytime and wrote science fiction at night.

真的吗？一个工程师，白天上班，晚上写书，写出来的书现在世界上这么多人在看？我的朋友看过，我以前的老师也看过。

Really? An engineer, working days, writing at night, and now so many people around the world are reading his book? My friends have read it. Even my old teacher has read it.

对，这在以前很难想。以前是我们看你们国家的作家，现在是你们在看我们的作家。你看到哪儿了？后面两本还没看吧？

Right, and that would have been hard to imagine before. It used to be us reading your country's writers. Now you're reading ours. How far are you? You haven't read the next two books, have you?

还没有，所以别告诉我后面的故事！但是我可以问一个问题吗？我看到第二本的名字叫《黑暗森林》，这是什么意思？你可以告诉我一点儿，但是别说太多。

Not yet, so don't tell me what happens! But can I ask one question? I saw that the second book is called The Dark Forest. What does that mean? You can tell me a little. Just don't say too much.

这个可以说，因为它不只是一个科幻故事，它是刘慈欣对一个老问题的回答。这个问题是：宇宙这么大，星星这么多，为什么我们到现在都没有发现外星人？为什么没有人给我们发消息？

That much I can say, because it's more than a science fiction story. It's Liu Cixin's answer to an old question. The question is: the universe is so big, there are so many stars, so why haven't we found any aliens by now? Why has nobody sent us a message?

对啊，我也想过这个问题。宇宙里应该有很多外星人吧？可是我们一个也没找到，一点儿声音也没听到。

Exactly, I've wondered about that too. There should be plenty of aliens out there, right? But we haven't found a single one, or heard a single sound.

刘慈欣的回答是：宇宙就像一个黑暗的森林。森林里很黑，你看不见别人，别人也看不见你。每个人手里都有刀，每个人都在安静地走路。在这样的森林里，如果你听到不远的地方有声音，你会大叫“我在这里”吗？

Liu Cixin's answer is that the universe is like a dark forest. The forest is pitch black. You can't see anyone else and no one can see you. Everyone is carrying a knife, and everyone is walking quietly. In a forest like that, if you heard a sound nearby, would you shout "I'm over here"?

当然不会。我不知道那个人是好人还是坏人。如果他是坏人，我一叫，他就知道我在哪儿了。

Of course not. I don't know whether that person is friendly or dangerous. If he's dangerous, the moment I shout, he knows exactly where I am.

对，就是这样。刘慈欣说，宇宙里的外星人可能也是这样想的。大家都害怕，所以大家都不说话。天上那么多星星，那么安静，可能不是因为宇宙里没有别人，是因为每个人都在黑暗里安静地听。

Right, that's exactly it. Liu Cixin says the aliens out there may think the same way. Everyone is afraid, so everyone stays silent. All those stars, so quiet. Maybe it's not because nobody else is out there. Maybe it's because everyone is sitting in the dark, quietly listening.

等等，这个想法让我有点儿害怕。那我们呢？我们一直在往天上发消息，地球不是已经大叫过“我们在这里”了吗？

Hang on, that idea actually scares me a little. What about us, then? We've been sending messages into the sky this whole time. Hasn't Earth already shouted "we're over here"?

你看，你已经开始用这本书的方法想问题了。这就是我喜欢这个作家的地方。他是工程师，想问题的时候特别清楚：如果这件事是真的，那下一件事会怎么样？很多科幻电影只给你看打来打去，他给你的是一个想法。你看完以后，晚上看天的时候，感觉都不一样了。

See? You're already thinking the way the book thinks. That's what I love about this author. He's an engineer, so his thinking is very clean: if this is true, then what happens next? A lot of science fiction movies just show you things blowing up. He gives you an idea. Once you've finished the book, looking at the night sky never feels the same.

真的是这样。昨天晚上看完书，我在外面站了很长时间。以前我觉得星星很漂亮，现在我觉得它们太安静了，安静得有点儿奇怪。

That's exactly what happened. Last night after I finished, I stood outside for a long time. I used to think the stars were beautiful. Now I think they're too quiet. Strangely quiet.

那我问你，如果宇宙真的是黑暗森林，我们现在应该怎么办？继续发消息，还是马上安静下来？

So let me ask you: if the universe really is a dark forest, what should we do now? Keep sending messages, or go quiet immediately?

我不知道。现在安静下来好像太晚了，我们已经叫了一百年了。但是我也不相信每个外星人都是坏人。森林里可能也有人想交朋友，对不对？

I don't know. Going quiet now seems too late. We've been shouting for a hundred years. But I also don't believe every alien is hostile. Someone in the forest might want to make friends too, right?

可能吧。刘慈欣也没说只能这么想，他只是把这个想法写得让你没办法不想它。快去看第二本吧，看完我们再谈，我现在什么都不告诉你。

Maybe. Liu Cixin never said this was the only way to think about it. He just wrote the idea so well that you can't stop thinking about it. Go read the second book. We'll talk when you're done. Until then I'm telling you nothing.