"It was their task to choose a Reality that would be most suitable to humanity. They modified endlessly - and the story goes into great detail, for I must tell you that it has been written in the form of an epic of inordinate length. Eventually they found (so it is said) a Universe in which Earth was the only planet in the entire Galaxy on which could be found a complex ecological system, together with the development of an intelligent species capable of working out a high technology.
"That, they decided, was the situation in which humanity could be most secure. They froze that strand of events as Reality and then ceased operations. Now we live in a Galaxy that has been settled by human beings only, and, to a large extent, by the plants, animals, and microscopic life that they carry with them - voluntarily or inadvertently - from planet to planet and which usually overwhelm the indigenous life.
"Somewhere in the dim mists of probability there are other Realities in which the Galaxy is host to many intelligences, but they are unreachable. We in our Reality are alone. From every action and every event in our Reality, there are new branches that set off, with only one in each separate case being a continuation of Reality, so that there are vast numbers of potential Universes - perhaps an infinite number - stemming from ours, but all of them are presumably alike in containing the one - intelligence Galaxy in which we live. - Or perhaps I should say that all but a vanishingly small percentage are alike in this way, for it is dangerous to rule out anything where the possibilities approach the infinite."
He stopped, shrugged slightly, and added, "At least, that's the story. It dates back to before the founding of Gaia. I don't vouch for its truth."
The three others had listened intently. Bliss nodded her head, as though it were something she had heard before and she were checking the accuracy of Dom's account.
Pelorat reacted with a silent solemnity for the better part of a minute and then balled his fist and brought it down upon the arm of his chair.
"No," he said is a strangled tone, "that affects nothing. There's no way of demonstrating the truth of the story by observation or by reason, so it can't ever be anything but a piece of speculation, but aside from that. Suppose it's true! The Universe we live in is still one in which only Earth has developed a rich life and an intelligent species, so that in this Universe - whether it is the all-in-all or only one out of an infinite number of possibilities - there must be something unique in the nature of the planet Earth. We should still want to know what that uniqueness is."
In the silence that followed, it was Trevize who finally stirred and shook his head.
"No, Janov," he said, "that's not the way it works. Let us say that the chances are one in a billion trillion - one in 1021 - that out of the billion of habitable planets in the Galaxy only Earth through the workings of sheer chance - would happen to develop a rich ecology and, eventually, intelligence. If that is so, then one in 1021 of the various strands of potential Realities would represent such a Galaxy and the Eternals picked it. We live, therefore, in a Universe in which Earth is the only planet to develop a complex ecology, an intelligent species, a high technology - not because there is something special about Earth, but because simply by chance it developed on Earth and nowhere else.
"I suppose, in fact," Trevize went on thoughtfully, "that there are strands of Reality in which only Gaia has developed an intelligent species, or only Sayshell, or only Terminus, or only some planet which in this Reality happens to bear no life at all. And all of these very special cases are a vanishingly small percentage of the total number of Realities in which there is more than one intelligent species in the Galaxy. - I suppose that if the Eternals had looked long enough they would have found a potential strand of Reality in which every single habitable planet had developed an intelligent species."
Pelorat said, "Might you not also argue that a Reality had been found in which Earth was for some reason not as it was in other strands, but specially suited in some way for the development of intelligence? In fact, you can go further and say that a Reality had been found in which the whole Galaxy was not as it was in other strands, but was somehow in such a state of development that only Earth could produce intelligence."
Trevize said, "You might argue so, but I would suppose that my version makes more sense."
"That's a purely subjective decision, of course..." began Pelorat with some heat, but Dom interrupted, saying "This is logic-chopping. Come, let us not spoil what is proving, at least for me, a pleasant and leisurely evening."
Pelorat endeavored to relax and to allow his heat to drain away. He smiled finally and said, "As you say, Dom."
Trevize, who had been casting glances at Bliss, who sat with mocking demurity, hands in her lap, now said, "And how did this world come to be, Dom? Gaia, with its group consciousness?"
Dom's old head leaned back and he laughed in a high-pitched manner. His face crinkled as he said, "Fables again! I think about that sometimes, when I read what records we have on human history. No matter how carefully records are kept and filed and computerized, they grow fuzzy with time. Stories grow by accretion. Tales accumulate - like dust. The longer the time lapse, the dustier the history - until it degenerates into fables."
Pelorat said, "We historians are familiar with the process, Dom. There is a certain preference for the fable. 'The falsely dramatic drives out the truly dull,' said Liebel Gennerat about fifteen centuries ago. It's called Gennerat's Law now."
"Is it?" said Dom. "And I thought the notion was a cynical invention of my own. Well, Gennerat's Law fills our past history with glamour and uncertainty. - Do you know what a robot is?"