"I'm sorry. Mr. Hartz is out. He won't be back today."

The screen drained of light and color.

Danner folded back the door and stood up. His knees were unsteady. The robot stood just far enough back to clear the hinge of the door. For a moment they faced each other. Danner heard himself suddenly in the midst of an uncontrollable giggling which even he realized verged on hysteria. The robot with the smear of food like a ribbon of honor looked so ridiculous. Danner to his dim surprise found that all this while he had been clutching the restaurant napkin in his left hand.

"Stand back," he said to the robot. "Let me out. Oh, you fool, don't you know this is a mistake?" His voice quavered. The robot creaked faintly and stepped back.

"It's bad enough to have you follow me," Danner said. "At least, you might be clean. A dirty robot is too much-too much-" The thought was idiotically unbearable, and he heard tears in his voice. Half-laughing, half-weeping he wiped the steel chest clean and threw the napkin to the floor.

And it was at that very instant, with the feel of the hard chest still vivid in his memory, that realization finally broke through the protective screen of hysteria, and he remembered the truth. He would never in life be alone again. Never while he drew breath. And when he died, it would be at these steel hands, perhaps upon this steel chest, with the passionless face bent to his, the last thing in life he would ever see. No human companion, but the black steel skull of the Fury.

It took him nearly a week to reach Hartz. During the week, he changed his mind about how long it might take a man followed by a Fury to go mad. The last thing he saw at night was the streetlight shining through the curtains of his expensive hotel suite upon the metal shoulder of his jail. All night long, waking from uneasy slumber, he could hear the faint creaking of some inward mechanism functioning under the armor. And each time he woke it was to wonder whether he would ever wake again. Would the blow fall while he slept? And what kind of blow? How did the Furies execute? It was always a faint relief to see the bleak light of early morning shine upon the watcher by his bed. At least he had lived through the night. But was this living? And was it worth the burden?

He kept his hotel suite. Perhaps the management would have liked him to go, but nothing was said. Possibly they didn't dare. Life took on a strange, transparent quality, like something seen through an invisible wall. Outside of trying to reach Hartz, there was nothing Danner wanted to do. The old desires for luxuries, entertainment, travel, had melted away. He wouldn't have traveled alone.

He did spend hours in the public library, reading all that was available about the Furies. It was here that he first encountered the two haunting and frightening lines Milton wrote when the world was small and simple-mystifying lines that made no certain sense to anybody until man created a Fury out of steel, in his own image.

But that two-handed engine at the door

Stands ready to smite once, and smite no more… Danner glanced up at his own two-handed engine, motionless at his shoulder, and thought of Milton and the long ago times when life was simple and easy. He tried to picture the past. The twentieth century, when all civilizations together crashed over the brink in one majestic downfall to chaos. And the time before that, when people were… different, somehow. But how? It was too far and too strange. He could not imagine the time before the machines.

But he learned for the first time what had really happened, back there in his early years, when the bright world finally blinked out entirely and gray drudgery began. And the Furies were first forged in the likeness of man.

Before the really big wars began, technology advanced to the point where machines bred upon machines like living things, and there might have been an Eden on earth, with everybody's wants fully supplied, except that the social sciences fell too far behind the physical sciences. When the decimating wars came on, machines and people fought side by side, steel against steel and man against man, but man was the more perishable. The wars ended when there were no longer two societies left to fight against each other. Societies splintered apart into smaller and smaller groups until a state very close to anarchy set in.

The machines licked their metal wounds meanwhile and healed each other as they had been built to do. They had no need for the social sciences. They went on calmly reproducing themselves and handing out to mankind the luxuries which the age of Eden had designed them to hand out. Imperfectly of course. Incompletely, because some of their species were wiped out entirely and left no machines to breed and reproduce their kind. But most of them minded their raw materials, refined them, poured and cast the needed parts, made their own fuel, repaired their own injuries and maintained their breed upon the face of the earth with an efficiency man never even approached.

Meanwhile mankind splintered and splintered away. There were no longer any real groups, not even families. Men didn't need each other much. Emotional attachments dwindled. Men had been conditioned to accept vicarious surrogates and escapism was fatally easy. Men reoriented their emotions to the Escape Machines that fed them joyous, impossible adventure and made the waking world seem too dull to bother with. And the birth rate fell and fell. It was a very strange period. Luxury and chaos went hand in hand, anarchy and inertia were the same thing. And still the birth rate dropped…

Eventually a few people recognized what was happening. Man as a species was on the way out. And man was helpless to do anything about it. But he had a powerful servant. So the time came when some unsung genius saw what would have to be done. Someone saw the situation clearly and set a new pattern in the biggest of the surviving electronic calculators. This was the goal he set: "Mankind must be made self-responsible again. You will make this your only goal until you achieve the end."

It was simple, but the changes it produced were worldwide and all human life on the planet altered drastically because of it. The machines were an integrated society, if man was not. And now they had a single set of orders which all of them reorganized to obey.

So the days of the free luxuries ended. The Escape Machines shut up shop. Men were forced back into groups for the sake of survival. They had to undertake now the work the machines withheld, and slowly, slowly, common needs and common interests began to spawn the almost lost feeling of human unity again.

But it was so slow. And no machine could put back into man what he had lost-the internalized conscience. Individualism had reached its ultimate stage and there had been no deterrent to crime for a long while. Without family or clan relations, not even feud retaliation occurred. Conscience failed, since no man identified with any other.

The real job of the machines now was to rebuild in man a realistic superego to save him from extinction. A self-responsible society would be a genuinely interdependent one, the leader identifying with the group, and a realistically internalized conscience which would forbid and punish "sin"-the sin of injuring the group with which you identify.

And here the Furies came in.

The machines defined murder, under any circumstances, as the only human crime. This was accurate enough, since it is the only act which can irreplaceably destroy a unit of society.

The Furies couldn't prevent crime. Punishment never cures the criminal. But it can prevent others from committing crime through simple fear, when they see punishment administered to others. The Furies were the symbol of punishment. They overtly stalked the streets on the heels of their condemned victims, the outward and visible sign that murder is always punished, and punished most publicly and terribly. They were very efficient. They were never wrong. Or at least, in theory they were never wrong, and considering the enormous quantities of information stored by now in the analogue computers, it seemed likely that the justice of the machines was far more efficient than that of humans could be.

Someday man would rediscover sin. Without it he had come near to perishing entirely. With it, he might resume his authority over himself and the race of mechanized servants who were helping him to restore his species. But until that day, the Furies would have to stalk the streets, man's conscience in metal guise, imposed by the machines man created a long time ago.

What Danner did during this time he scarcely knew. He thought a great deal of the old days when the Escape Machines still worked, before the machines rationed luxuries. He thought of this sullenly and with resentment, for he could see no point at all in the experiment mankind was embarked on. He had liked it better in the old days. And there were no Furies then, either.

He drank a good deal. Once he emptied his pockets into the hat of a legless beggar, because the man like himself was set apart from society by something new and terrible. For Danner it was the Fury. For the beggar it was life itself. Thirty years ago he would have lived or died unheeded, tended only by machines. That a beggar could survive at all, by begging, must be a sign that society was beginning to feel twinges of awakened fellow feeling with its members, but to Danner that meant nothing. He wouldn't be around long enough to know how the story came out.

He wanted to talk to the beggar, though the man tried to wheel himself away on his little platform.

"Listen," Danner said urgently, following, searching his pockets. "I want to tell you. It doesn't feel the way you think it would. It feels-"

He was quite drunk that night, and he followed the beggar until the man threw the money back at him and thrust himself away rapidly on his wheeled platform, while Danner leaned against a building and tried to believe in its solidity. But only the shadow of the Fury, falling across him from the street lamp, was real.

Later that night, somewhere in the dark, he attacked the Fury. He seemed to remember finding a length of pipe somewhere, and he struck showers of sparks from the great, impervious shoulders above him. Then he ran, doubling and twisting up alleys, and in the end he hid in a dark doorway, waiting, until the steady footsteps resounded through the night.

He fell asleep, exhausted.

It was the next day that he finally reached Hartz.

"What went wrong?" Danner asked. In the past week he had changed a good deal. His face was taking on, in its impassivity, an odd resemblance to the metal mask of the robot.