“Thank you for your candor. I’m aware that not only is there disagreement among you now, but also there will be generations between now and when I leave, and generations on board the ship. The children may not like being bound by the promises of a previous generation.”

“As you said. We are human.”

“So you will understand and forgive me, I think, if I treat the mice who come with me as if there were no promise. I will check constantly. I will assume you are trying to cheat on our agreement.”

“We never cheat.” “We give our word.” “You’re a fool if you think we’re lying.”

“I think you’re telling the truth,” said Noxon. “I think I can trust you enough to take six mice. None of them pregnant.”

“Not enough,” they said at once. “At least twenty.”

And from that Noxon concluded that they needed at least twenty mice in order to . . . what, move objects through spacetime? Or simply to establish a viable gene pool? No point in asking; he wouldn’t trust the answer to be complete. They always intended many different things at once. It was like trying to blow smoke away. It swirled and eddied but you were never in control of it.

“Bring thirty,” Noxon said. “In case I accidentally step on a few of you.”

They might or might not have a sense of humor. Whether they took this as irony or as a threat didn’t really matter to Noxon at the moment.

“When do we go?” “How long till we go?”

Those were excellent questions. He should say good-bye to Param and let her know she was on her own. Or should he first take her to Olivenko? Or wait until he could unite the whole group?

It was enough if one of them knew that he had gone. Param could tell the others. Noxon was the extra Rigg, the expendable one. No reason to act as if he thought he would be missed. When he left, there would be exactly the right number of Riggs in the world.

“Stay here,” he said. “And by that I mean—everybody off me and out of my clothes. That includes the five clinging to the insides of my trouser legs, the three on my arms . . .”

They knew that they couldn’t fool the facemask. They scampered or leapt, and in a moment they all stood around him in a circle.

“It isn’t very promising when you already try to sneak one stowaway with me.”

They put on a good show of consternation, and it’s true that the one who was still clinging to the back of his shoe looked small. He might really be as young and foolish as they said. Or he might have been of a small breed.

You can’t trust the mice.