“Still, their point is valid,” said Noxon. “We don’t have to leave a living ship to be picked up in the high-technology future. We’re going to come back to the beginning of the ice age to pick it up. So whatever happens between the time we leave the ship and the far future, when we find out why the Visitors attack Garden, doesn’t matter.”
“You’re suggesting that we kill everybody aboard?” said Ram Odin.
“Without stasis fields, all the colonists will rot away within a few decades, no matter how strong the seal on their sleep chambers is,” said the expendable.
“So the kindest thing,” said Ram Odin to the expendable, “would be to park the ship where we know the ice will form, kill everybody aboard, leave you awake long enough to make sure it’s fully covered with ice, and then you shut everything down permanently.”
Killing everybody aboard would obviously include the mice, unless Noxon took them with him into the future. Which he clearly had no intention of doing, since they could not be trusted.
The mice started a few feeble protests. But Noxon could hear them convincing each other that the plan made sense.
“There isn’t a hundred thousand years of life support for us, even though our needs are few,” said a spokesman for the mice. “Covered with ice, it would be very difficult to do the necessary air exchange. But instead of killing us, you should bring us with you.”
“Nice try,” said Noxon. “Even if you don’t take over the ship, all you have to do is start having babies while humans are still evolving, and if you permit us to survive at all, I have a feeling it will still be a world run by mice.”
“We promise we won’t!” cried the mouse in despair.
“I think they have to get back in the box,” said Noxon. “Then we give them a week, to give us time to get back from the future, send for the flyer, and return to take off again. So, my dear expendable,” he said, “will you take care of shutting down all life support on the ship a week after we leave?”
“Will I really have to do it?” said the expendable. “Won’t you be back before the week is up?”
Noxon shook his head. “You have to live through the version of events in which we don’t come back. But when we do come back, the version of you that we meet will never experience the complete shutdown, so that version will be sure that you never had to kill the mice and the colonists.”
“That doesn’t make sense,” said Ram Odin. “I take your word for it, but . . .”
“I exist at all,” said Noxon, “because there was a version of me, Rigg Sessamekesh, that killed a version of you, Ram Odin—a much older version—in order to keep him from killing me first. That actually happened, and the version of me that is still called Rigg actually did the killing. Just as a version of the expendable will shut down the life support and observe as the mice and all the colonists die.”
“So does that mean there’ll be two of me?” asked the expendable.
“No,” said Noxon. “Because once this ship goes cold, it’s completely out of the causal chain. When we return, nothing that happened after we left will have affected Ram and me in any way. So the dead version of the ship won’t exist once we make the change.”
“You say that as if you knew what you were talking about,” said Ram Odin.
“Because I do know,” said Noxon. “The only person who gets copied is the one who is part of the causal chain. So when Rigg prevented himself from killing that older version of you, Ram, it created a second Rigg—me, the one that didn’t kill you—but not a second Ram Odin.”
“Except here I am,” said Ram Odin.
“You’re the twentieth Ram Odin left over from an earlier division, and you know it,” said Noxon. “You’re just being frivolous.”
“I am,” said Ram Odin. “I think the plan will work.”
“You talk about trusting us!” cried the mice. “But how can we trust you!”
“The mice are having trust issues,” said Noxon.
“The first time they tried to take over the ship, they signed their death warrants,” said Ram Odin. “Even if we never come back, they’ve had a day of life that they didn’t deserve.”
“Here’s why you can trust us,” said Noxon to the mice. “First, unlike you, we haven’t broken our word over and over again. Second, I could have you killed at any time and I haven’t, so why would I need to go to all this elaborate preparation to kill you now? If I don’t want you alive, you’re dead whenever I want. You can’t hide on my body if I take off my clothes, and you can’t hide anywhere else because the expendable can turn off the life support.”
“So I’m giving you continuous evidence that I am committed to your survival—provided you don’t endanger the survival of the human race, which means you stay in this ship and die with it.”
“I don’t know why you brought the mice along in the first place,” said Ram Odin.
“Because two of the wallfolds on Garden are shared with billions of sentient mice. I may need these as witnesses of what we do here. Or if I conclude that we do have to destroy the human race on Earth, then the mice can do it more easily and thoroughly than I can.”
“You’re the version of Rigg that isn’t murderous?” said Ram Odin.
“I’m here to save Garden,” said Noxon. “And it’s humans from Earth who destroy it. You do the math.”