Hari wondered if some of the samples might be dangerous, but both Maserd and Mors Planch had thrown back the hoods of their radiation suits, and they had more life span to risk than Hari.

Horis showed clear pride in his collection. “I’ve been busy, as you can see. Of course there’s only been time for a cursory sampling. But the Earthlings are most cooperative, sending boys in all directions to take samples for me.”

Hari caught Maserd’s indulgent smile and agreed. Let Horis have his moment. There would be time to discuss more important matters before evening came.

“And what have you determined so far?”

“Oh, a great deal! For example, did you know that the best soils in this area are not of Earthly origin at all? There are several sites, not far from Chica, where many hectares of rich loam were laid down. The material is unmistakably from Lorissa World, over twenty light-years away. It was brought here and spread in a neat, organized fashion. Someone was trying to restore this planet! I date the effort at approximately ten thousand years ago.”

Hari nodded. This fit what Gornon said earlier-that the empire once attempted restoration of the homeworld, before changing its mind, closing the universities and hauling millions away from their homes, leaving behind only a race of hardscrabble survivors.

“But there’s more!” Horis Antic insisted, moving to where he had set up several instruments. “I stayed up all night, studying emanations from thatthing the ancients sealed away, over there.”

Horis pointed to the massive steel-and-concrete sarcophagus nearby, and the cracked entryway that R. Gornon’s laborers were seeking to access with spindly scaffolding.

“I don’t have the right tools or expertise. But it’s clear some kind ofrift in the continuum was made here, once upon a time. It’s quiescent now, but the effects must be powerful when the thing is roused. I was skeptical of that tiktok-the one posing as Gornon Vlimt-when it talked abouthurling someone forward in time. But now I wonder.”

The bureaucrat-scientist grimaced. “What Ican say-and the robot may not have told you-is that even while the space-time rift is dormant, there are effects that permeate this entire planet. One of the most notable is a shift in the stability of uranium oxide, a lightweight molecule found in hydrothermal regions on most Earthlike planets. Only here, there is a slightly higher predisposition for the constituent atoms to”

Hari blinked, abruptly realizing something. He had been told that Earth’s transformation into a radioactive world came from the decision of a single robot, during the post-chaos age. But might the seeds have been sown even earlier? In the bright renaissance when Susan Calvin and her contemporaries saw no limits to their ambition or power?

What if Giskard only amplified something that had already begun? Might that let Daneel’s folk off the hook? Could it explain why this effect only happened once? On Earth?

Horis would go on, enthusiastically explaining details of an ancient tragedy. But he was interrupted by the dinner bell…which meant partaking of Earthling hospitality, alas. R. Gornon felt it would crush their pride if the visitors refused.

Hari managed to swallow a few bites of a nondescript gruel, and smiled appreciatively before excusing himself. Slowly ascending the mound of rubble, he sat facing the three ruined cities and pulled from his pocket the latest copy of the Seldon Plan Prime Radiant.

He felt a little guilty for having swiped Wanda’s copy, but his granddaughter wouldn’t notice or care. She and Gaal Dornick were still aboard their ship, wired to sleep machines until tonight’s proceedings.

Soon I must decide, whether to go ahead five centuries…assuming this thing works as advertised, and doesn’t merely rip my atoms apart.

He smiled at that. It seemed an interesting way to go.

Anyway, what have I got to-

All of a sudden, the sky shook with pealing thunder-a sonic boom. He glanced up. Where a few stars had begun to shine, a bright object streaked overhead, a winged cylinder that banked and turned, obviously coming in for a landing.

Hari sighed. He had been hoping to lose himself for an hour or two amid his beloved equations. The new mathematical model that had emerged-a pattern for the future-was enthralling to contemplate, but the ideas already floated inside his head, and he was certain that double-checking the Prime Radiant wouldn’t change anything.

With some effort, he gathered strength to lift his frail body. Flickering patches of radiation lit his way, following the twisty trail back to camp.

By the time he got there, the new visitors had already arrived.

A pair of women stood near R. Gornon Vlimt. One of them turned and smiled, as Hari approached the Earthlings’ campfire.

“The guest of honor, I presume?”

Gornon’s expression gave away little.

“Professor Seldon, let me introduce Zorma and Cloudia. They have come a great distance, in order to witness tonight’s activities, and to assure themselves that you aren’t under any sort of coercion.”

Hari laughed. “My entire life has been guided by others. If I know more and see more than my fellow humans, it’s because that serves some long-range plan. So, tell me, what fashion of robots are you?” he asked the two newcomers. “Are you yet another sect of Calvinians? Or do you represent Daneel?”

The one called Zorma shook her head. “We’ve been disowned by Calviniansand Giskardians. Both groups call usperverts. Yet they still find us useful, whenever something important is about to take place.”

“Perverts, eh?” Hari nodded. It all fit. “So which of you is the human?”

Cloudia brought a hand to her chest. “I was born one of the masters, long ago. But this new body of mine is at least one-quarter robotic. Zorma, here, has many protoplasmic parts. So your question is a complicated one, Professor Seldon.”

Hari glanced at R. Gornon, whose face revealed nothing, even though it could simulate the whole range of emotions.

“I see why the other positronic sects find your approach disturbing,” Hari commented.

Zorma nodded. “We seek to heal the rift between our races by blurring the distinction. It has been a long and costly project, and not entirely successful. But we continue to hope. The other robots put up with us, because it would cause them serious mental dissonance if they tried to eliminate us.”

“Of course, if you are part human, you get some protection under the First Law.” Hari paused. “But that won’t suffice by itself. There must be something more.”

Cloudia agreed. “We also provide a service. We bear witness. We don’t take sides. We remember.”

Hari could not help being impressed. This small sect had maintained its existence for a long time, enduring the contempt of far greater forces, while maintaining some degree of independence in an age when human memory was shrouded by amnesia. It would take great discipline and patience to abide centuries this way, resisting the ever-present urge to act. In some ways, it required a spiritopposite to Mors Planch’s. In fact, it would take people almost exactly like

He turned, seeking one face amid the crowd of onlookers, scanning past Horis, Sybyl, the Earthlings, and Mors Planch.

Hari’s gaze settled on the nobleman from Rhodia, Biron Maserd, who stood back from the crowd, with his arms crossed, wearing an expression of indifference. Hari saw through the guise now.

“Come forth, my young friend,” he urged the tall lord. “Come join your comrades. Let us have no more secrets between us. It is a time for truth.”