After three days, thousands of samples had been brought aboard and stored in the gene banks. The conclusion was clear. Most of the proteins that humans needed could be found readily among the native flora and fauna on both worlds. And a simple array of fast-spreading, highly edible plants would make up the deficiencies. “We can release any Earth fauna we choose,” said Wheaton, “and thus we’ll have meat to eat and enough plants for a varied and pleasing diet.”

“That’s what they’ve found on the other world,” said the expendable, “except that they need to spread a different array of Earth plants.”

“So, no destruction?” asked Noxon.

“Are you disappointed?” asked Ram.

“I still think that walls are a good idea,” said Noxon.

“Because you grew up in a wallfold,” said Ram.

“We can give the mice one wallfold,” said Noxon. “And reserve one on each world for the aliens alone.”

“And give us one to combine with them,” said the alpha mouse.

“If we give one wallfold to aliens and mice together, we have to make sure there’s a tight lid on their technology,” said Noxon. “I’m afraid of what their combined abilities might lead to.”

“Happiness and peace for all sentient species everywhere,” said the alpha mouse.

“No doubt,” said Noxon.

“Same discussion on most of the other ships,” said the expendable.

“Most?” asked Ram. “So we’ve diverged?”

“Two ships on the far world and one here have to deal with a Wheaton with a broken hip,” said the expendable. “It slowed down the decision making.”

“I thought you’d protect me,” said Wheaton accusingly.

“I can’t always anticipate the stupid choices of human beings,” said the expendable.

“Stop bickering,” said Ram. “Dividing up the world is the obvious choice. We have to decide what to do with the extra humans who won’t be needed to found a colony in three of the wallfolds.”

“We can establish more wallfolds than we have ships,” said Noxon. “Let’s make thirteen colonies on each world, ten for humans, one each for aliens and mice, and one for both.”

“Must there also be a colony that includes both mice and humans?”

“I hope not,” said Wheaton.

“Of course,” said Noxon.

“At least don’t let ours be that colony!” said Wheaton.

“You’ll get used to them,” said Noxon.

“That means you already agreed to have ours be the human colony that has mice,” said Wheaton.

“Unless you plan to mate and settle down, Professor,” said Ram, “I think all the copies of you should regularly visit all the colonies. Sleep in stasis in between inspections. See how the alien species are developing, now that they have humans and mice interfering.”

“Assisting,” corrected the alpha mouse. “At least that’s what we’ll be doing.”

“I think that’s an excellent plan,” said Wheaton. “I only wish I could publish my findings.”

“You should write down everything you see and conjecture,” said Ram, “and we’ll eventually share it with every world.”

“One more need,” said the expendable. “A name for each of these worlds.”

“‘Garden’ is already taken,” said Noxon.

“I don’t think the worlds should be named for any of us,” said Wheaton.

“Never crossed my mind,” said Ram.

“Said the man with two wallfolds named for him,” said Noxon.

“I didn’t name them,” said Ram. “I’ve never been there.”

“How about Roach and Tripod?” asked Noxon.

“‘Roach’ is hardly expressive of a desire to get along with them,” said Wheaton.

“All that ‘Roach’ will mean in a generation or two will be the name of a world,” said Noxon.

“The human settlers will know from the start,” said Ram. “They may never let go of the associations. We need them to speak of the natives with respect, at least inside the shared wallfold.”

“Melody and Harmony,” said the alpha mouse.

“Just as I was thinking ‘Noise’ and ‘Nasty,’” said Noxon, “the mice suggested ‘Melody’ and ‘Harmony.’”

“As long as this is the world that’s called Melody,” said Ram. “We came here first.”

“And we have such lovely voices,” said Wheaton.

Other suggestions were made on other ships, but in the end the idea of Melody, though attractive to most, was superceded: One world was named Treble, since the Tripods had high and piping voices, while the other was named Bass, because the Scuttles made sounds that were so low that many of them could not be heard by humans. Neither species had anything that could be called a language yet.

Thirteen wallfolds on each world, with the native species each confined to the area where, in the original timestream, they had achieved full sentience. The mice were satisfied, and the natives didn’t get a vote, so everything proceeded peacefully.

Inside every wallfold that included a Noxon, he and the expendable made a jaunt into the far future, not just to see how their own colony had fared, but to check the wallfolds that contained either mice or natives, or both. The orbiters provided firm calendar dates based on stellar positioning, so that the Noxons could observe both the year when their ships arrived and the year when Earth had been invaded in the old timestream.

There were no spaceships in any of the futures, nor technologies that allowed communication between wallfolds, except by way of the expendables. The natives had evolved sentience in all four native wallfolds, though whether they were the same as they would have been without human interference, it was impossible to say. In each wallfold shared with mice, the natives and the mice were at peace, and the Scuttles and their mice had evolved a system of shared cities, with some dominated by the Scuttles and some by the mice. The Tripods were less cooperative—with the mice and with each other. They were torn by warfare, but so were most of the human wallfolds, so that was hardly a reason to make any changes.

The visiting Noxons all reached the conclusion that their original mission—to keep these aliens from destroying the human race—had been achieved, and it had been done without depriving the proto-sentients of a chance to achieve their evolutionary potential.

Then the Noxons of each world met with each other in one of the grounded spaceships and conferred about the only important decision remaining to them.

“There’s a lid on development of technology,” said the first speaker in each conference, “but we represent something far more dangerous than any weapon or tech. The ability to go into the past and wipe out whole timestreams. We had to use that ability when the future of humanity was at stake. But now, will Treble and Bass be better off if these timeshaping genes are part of the mix, or if we allow our abilities to be extinguished by not reproducing?”

And in both conferences, another Noxon pointed out the obvious. “There are timeshapers on Garden, no matter what we do here. And Ram Odin has already married and had children in every human wallfold. He was the source of these genes in the first place.”

And another said, “The mice knew how to send objects through time and space when they got here. They knew how to manipulate human genes to create the original Rigg and Param and Umbo. We’d be fools to think they’ve forgotten that knowledge. For all we know, they all have the ability to manipulate time. Should we let the mice have such power, while we give up our only possible remedy?”

“So we keep the ability in the gene pool? So that we aren’t at the mercy of the mice? Or the humans from Garden, if they ever come here?”

“This ability exists in the universe. We’d be fools to throw it away, when we might need it someday. It saved us once.”

“But only because people of extraordinary decency and wisdom wielded it.” And while they all laughed at such ironic self-deprecation, they also knew that it was true.

“Sentience always carries with it the power of destruction. We must work to make sure that decency and wisdom are part of the heritage of every wallfold, and then trust our descendants to use this power responsibly, if they have it at all.”