Every person who is alive now has thirty ghosts standing behind him, because since the beginning of human beings, the number of dead people is exactly thirty times that of the living people.About 100 billion people have infested the planet Earth since the dawn of time. That number is interesting only because, by an odd coincidence, there also happen to be about 100 billion stars in our own universe—the Milky Way.So in this universe, every person who has lived has a star shining in the sky. All of these stars, however, are suns, and generally more brilliant than the small, nearby star we call our sun.And, many—perhaps most—of these exotic stars have their own planets orbiting them.It is almost certain, therefore, that there is enough land in the sky to give man--including the most primitive ape-men--a piece of land each, and to provide each with a private heaven or hell.

In all these potential heavens and hells, how many, and what kind of creatures, are inhabited; the nearest of them to the earth is a million times farther than Mars or Venus, and this The two planets are only a distant goal for our next generation.However, the barrier of distance is disappearing, and one day we will meet in the interstellar with some kind of creature that can rival us and even dominate us. Humanity has been slow to face up to this prospect; and there are still some people today who hope that this prospect will never be realized.However, more and more people ask: "Since we are about to enter the space, why hasn't this encounter happened yet?"

Indeed, why?Here is one possible answer to this perfectly reasonable question.But remember: this is just a fictional story. The real situation is bound to be more thrilling.