He stopped to prowl through an empty house and an empty garage. He came out with a flashlight, a box of tools, and a crowbar. He had no certain plan, but tools would be needed if he meant to call a temporary halt to Central's activities. It was dangerous to enter any building, however; Central would call it burglary, unless the prowler could show legitimate reason for entering. He needed some kind of identification.

After an hour's search through several houses in the residential district, he found a billfold containing a union card and a pass to several restricted buildings in the downtown area. The billfold belonged to a Willie Jesser, an air-conditioning and refrigeration mechanic for the Howard Cooler Company. He pocketed it after a moment's hesitation. It might not be enough to satisfy Central, but for the time being it would have to do.

By early afternoon he had reached the beginnings of the commercial area. Still he had seen no signs of human life. The thinly scattered traffic moved smoothly along the streets, carrying no passengers. Once he saw a group of robot climbers working high on a telephone pole. Some of the telephone cables carried the coordinating circuits for the city's network of computers. He detoured several blocks to avoid them and wandered on glumly. He began to realize that he was wandering aimlessly.

The siren came suddenly from half a block away. Mitch stopped in the center of the street and glanced fearfully toward it. A robot cop was rolling toward him at twenty miles an hour! He broke into a run.

"You will halt, please!" croaked the cop's mechanical voice. "The pedestrian with the toolbox will please halt!"

Mitch stopped at the curb. Flight was impossible. The skater could whisk along at forty miles an hour if he chose.

The cop's steel wheels screeched to a stop a yard away. The head nodded a polite but jerky greeting. Mitch stared at the creature's eyes, even though he knew the eyes were duds; the cop was seeing him by the heat waves from his bodily warmth, and touching him with a delicate aura of radar.

"You are charged with jaywalking, sir. I must present you with a summons. Your identification, please."

Mitch nervously produced the billfold and extracted the cards. The cop accepted them in a pair of tweezerlike fingers and instantly memorized the information.

"This is insufficient identification. Have you nothing else?" "That's all I have with me. What's wrong with it?" ^"The pass and the union card expired in 1987."

Mitch swallowed hard and said nothing. He had been afraid of this. Now he might be picked up for vagrancy.

"I shall consult Central Coordinator for instructions," croaked the cop. "One moment, please."

A dynamotor purred softly in the policeman's cylindrical body. Then Mitch heard the faint twittering of computer code as the cop's radio spoke to Central. There was a silence lasting several seconds. Then an answer twittered back. Still the cop said nothing. But he extracted a summons form from a pad, inserted it in a slot in his chassis, and made chomping sounds like a small typesetter. When he pulled the ticket out again, it was neatly printed with a summons for Willie Jesser to appear before Traffic Court on July 29, 1989. The charge was jaywalking.

Mitch accepted it with bewilderment. "I believe I have a right to ask for an explanation," he muttered.

The cop nodded crisply. "Central Service units are required to furnish explanations of decisions when such explanations are demanded."

"Then why did Central regard my identification as sufficient?"

"Pause for translation of Central's message," said the cop. He stood for a moment, making burring and clicking sounds. Then: "Referring to arrest of Willie Jesser by unit Six-Baker. Do not book for investigation. Previous investigations have revealed no identification papers dated later than May 1987 in the possession of any human pedestrian. Data based on one hundred sample cases. Tentative generalization by Central Service: It has become impossible for humans to produce satisfactory identification. Therefore, `satisfactory identification' is temporarily redefined, pending instruction from authorized human legislative agency."

Mitch nodded thoughtfully. The decision indicated that Central was still capable of "learning," of gathering data and making generalizations about it. But the difficulty was still apparent. She was allowed to act on such generalizations only in certain very minor matters. Although she might very well realize the situation in the city, she could do nothing about it without authority from an authorized agency. That agency was a department of the city government, currently nonexistent.

The cop croaked a courteous, "Good day, sir!" and skated smoothly back to his intersection.

Mitch stared at his summons for a moment. The date was still four days away. If he weren't out of the city by then, he might find himself in the lockup, since he had no money to pay a fine. Reassured now that his borrowed identity gave him a certain amount of safety, he began walking along the sidewalks instead of using the alleys. Still, he knew that Central was observing him through a thousand eyes. Counters on every corner were set to record the passage of pedestrian traffic and to relay the information to Central, thus helping to avoid congestion. But Mitch was the pedestrian traffic. And the counters clocked his passage. Since the data were available to the logic units, Central might make some unpleasant deductions about his presence in the city.

Brazenness, he decided, was probably the safest course to steer. He stopped at the next intersection and called to another mechanical cop, requesting directions to City Hall.

But the cop paused before answering, paused to speak with Central, and Mitch suddenly regretted his question. The cop came skating slowly to the curb.

"Six blocks west and four blocks north, sir,^" croaked the cop. "Central requests the following information, which you may refuse to furnish if you so desire: As a resident of the city, how is it that you do not know the way to City Hall, Mr. Jesser?"

Mitch whitened and stuttered nervously, "Why, I've been gone three years. I…I had forgotten."

The cop relayed the information, then nodded. "Central thanks you. Data have been recorded."

"Wait," Mitch muttered. "Is there a direct contact with Central in City Hall?"

"Affirmative."

"I want to speak to Central. May I use it?"

The computer code twittered briefly. "Negative. You are not listed among the city's authorized computer personnel. Central suggests you use the Public Information Unit, also in City Hall, ground floor rotunda."

Grumbling to himself, Mitch wandered away. The P.I.U. was better than nothing, but if he had access to the direct service contact, perhaps to some extent he could have altered Central's rigid behavior pattern. The P.I.U. however would be well guarded.

A few minutes later he was standing in the center of the main lobby of the City Hall. The great building had suffered some damage during an air raid, and one wing was charred by fire. But the rest of it was still alive with the rattle of machinery. A headless servo-secretary came rolling past him, carrying a trayful of pink envelopes. Delinquent utility bills, he guessed.

Central would keep sending them out, but of course human authority would be needed to suspend service to the delinquent customers. The servo-secretary deposited the envelopes in a mailbox by the door, then rolled quickly back to its office.

Mitch looked around the gloomy rotunda. There was a desk at the far wall. Recessed in a panel behind the desk were a microphone, a loudspeaker, and the lens of a television camera. A sign hung over the desk, indicating that here was the place to complain about utility bills, garbage-disposal service, taxes, and inaccurate weather forecasts. A citizen could also request any information contained in Central Data except information relating to defense or to police records.