The horizon glowed.

The sky of planet Earth shimmered with countless scintillations, individual sparks that rivaled the scattered stars for possession of night. Near the ground, one could almost imaginehearing the soft crackle of radiation, whose intensity varied wildly from place to place. In some patches it was terribly intense. Through goggles provided by the robot Gornon Vlimt, those sites revealed themselves with eerie fluorescence, as if ghosts were trying to ooze upward, struggling to escape the tortured ground.

Pride of Rhodiahad landed near one of the “safe spots,” a former city site hugging the coastline of a long freshwater lake that frothed with scummy green-and-purple algae. From atop a huge mound of broken masonry, Hari could discern the outlines ofthree ancient cities, one crowding up against the ruins of the next.

Most recent and least impressive was a jumble of relatively modern-looking arcology-habitats of Topan Style, from the early Consolidation Era of the Trantorian Empire-the last time Earth had a fair-sized population, numbering almost ten million.

Just southward along the lakeshore stood a truly mammoth structure, a city that was impressive both by galactic standards and by how very old it was. A vast self-contained unit-extending far underground-that once protected its inhabitants from the wind, rain, and, above all, having to look upon a naked sky.

It wasn’t radioactivity that caused the thirty million inhabitants of New Chicago to huddle together so. Earth had still been green and vibrant when this beehive metropolis thrived. In fact, the habitat only started to empty when the fecund soil began turning lethal…when those who could depart fled for the stars in a great, panicky diaspora. Until that awful exodus, vast numbers of people thronged the giant enclosed city, separated from nature by only a thin shell of steel.

No, the thing that drovesomany otherwise healthy people to cower so, away from all pleasures of sunshine, was the same deadly enemy I fought all my life. This metropolis was an early object lesson in the dangers of chaos.

Beyond the huge squat dome, there stood yet another city-Old Chicago, Gornon had called it-a tumulus of fallen buildings from an even earlier age, less technologically advanced. And yet, Hari’s goggles amplified the distant view, sweeping his gaze along graceful arcs of highways more daring and lovely than any to be seen on an imperial world. Some of the tallest buildings still stood, and their unabashedly ambitious architecture made his heart leap. The ancient metropolis had been built by people with a boldness of spirit that their descendants in New Chicago apparently lacked.

Somethinghad happened to smash that boldness.

I’ve given it names. My equations describe the way it seductively draws in the best and brightest, eventually transforming them into solipsists who rage against their neighbors. And yet, I confess I’ll never understand you, Chaos.

The robot Gornon stood nearby, resembling a human in every way except his attire. He wore normal street clothes, while Hari-and his two human friends, farther down the slope-were accoutered in one-piece outfits that offered safety from the sleeting rays.

“Old Giskard Reventlov made a fantastic decision, transforming all of this into a wasteland, wouldn’t you say, Professor Seldon?”

Hari had been expecting Gornon’s question. How could he answer?

The universe was turned topsy-turvy. Humans were the creators and gods, who had no power, no memory, and almost no volition-only mortality. The created-servants were in charge, as they had been ever since that day when an omnipotent angel cast mankind firmly out of its first Eden. Hari could barely encompass the concept with his mind. To truly understand it was quite beyond him.

And yet, the mathematics implies…

Gornon persisted. “At least you can see why a majority of robots at first resisted Daneel’s innovation, his Zeroth Law. They saw the pain it caused and chose to rally around the banner of Susan Calvin.”

“Well, it did you little good. Your civil war resulted in a power vacuum. While two main factions of robots fought it out, the Auroran followers of Amadiro were free to unleash their pitiless terraformers, without interference or human guidance. Anyway, when the war finally did end, Daneel had the final say.”

“I concede that Olivaw had an advantage from the start. The Zeroth Law was especially attractive to some of the brightest positronic minds. They had been looking for some way to deal with the inevitable contradictions created by the first Three Laws.”

Hari smirked. “Contradictions? Like kidnapping an old man and dragging him halfway across the galaxy to a poisoned planet? How does that jibe with your precious First Law of Robotics?”

“I think you know the answer, Professor. Daneel Olivaw won the civil war, not only by taking control, but in a much larger sense as well. There simply are no pure Calvinians anymore. The old religion is impossible to maintain under present circumstances. We all believe insome version of a Zeroth Law. In the paramount importance of humanity-as opposed to any single human being.”

“But you differ over what specific course will be good for us in the long run.” Hari nodded. “Fair enough. So here I am, on fabled Earth. Your clique went to great effort and took tremendous risks to bring me here. Now won’t you tell me what you want? Is it something like what Kers Kantun asked for, back in the nebula? Do you want my human permission to destroy something that you’d rationalize destroying anyway?”

There followed a long pause. Then Gornon answered, “In one sense, you describe our intention exactly. And yet, I doubt that even you can imagine what I am about to propose.

“Several times in recent months-and even in recordings you made for the Foundation-you have said that you wished for some way to see the fruits of your labors. That you could witness the unfolding of your great Plan, and see humanity transform during the coming thousand years. Did you really mean that?”

“Who wouldn’t want to witness a seed grow into a mighty tree? But it’s only a dream. I live now, at the end of one great empire. It is enough that I can foresee a bit of the next.”

“Do you prophesy your Plan unfolding smoothly for the next hundred years?”

“I do. Almost no perturbation can interfere over that timescale. The socio-momentum is so great.”

“And two hundred years? Three hundred?”

Hari felt peevishly inclined not to cooperate with this questioning. And yet, the equations flew out of recesses in his mind, flocking together and creating a vast swirl, as if beckoned by Gornon’s question.

“There are several ways that the Plan might get into trouble on that timescale,” he answered slowly, reluctantly. “There is always the danger of some new technology upsetting things, although most of the important advances will take place on Terminus. Or some fluke might occur having to do with human nature-”

“Such as the advent of human mentalics?”

Hari winced. Of course some Calvinians were already aware of the new mutation.

When he did not answer, Gornon continued, “That’s when you felt it all start slipping away, isn’t it, Professor? If mentalics could crop up once, they might do so a second time, almost anywhere. To deal with that contingency, your Second Foundation had to incorporate these psychic powers. Instead of a small order of monastic-mathematical monks, they must become a new species…a master race.”

Hari’s voice felt rough in his throat.

“A strong Second Foundation acts like a major damping force…keeping the equations stable and predictable for another several centuries…”