"You can survive that?"

"Of course. Already we have endured tens of times that interval. However, I must mention two other anomalous features of the received signals. First, although there are many signals, million after million of them, they clearly fall into two different types."

"How do you know that, if you can't understand what they say?"

"By statistical analysis of the bit streams. That analysis clearly reveals two distinct types, although the content of either type remains unknown. And that is the second anomaly. In principle, my analytical tools should permit the interpretation of any possible signal whatsoever. It makes no difference if the sender is human or nonhuman, organic or inorganic, familiar or utterly alien. If the laws of logic, which we have always believed to be universal, are being followed, the signal should be intelligible."

"But these are not? Very curious. Chances are it will be easier to sort out what's going on when we're there to see it."

But Drake was expressing a confidence that he did not feel. He sensed old memories stirring within him. Two kinds of signal that clearly were signals, but neither of which could be interpreted. Why did that sound familiar?

"First, switch me back to electronic storage. Then send me on my way. After I'm gone, you can take the slow road and join me." Signals that could not be understood. Algorithms that should be able to interpret anything, but failed to do so. He postponed the question. He would have time to consider it when he reached the signal source. "Let's get me to electronic form, so I can go to work. Assuming that things work out all right, I'll beam myself back here and tell you what's going on."

Assuming that things work out all right.

It occurred to Drake, rising to consciousness, that nothing had gone right for aeons. They had certainly not gone right this time. Rather than waking in some other galaxy, delivered as an S-wave and reconstructed to consciousness, he was still on board the ship. And although he was awake, he was certainly not embodied. Instead he was in electronic form, sharing sensors and processors with the ship. He was also aware of the hundred or more other versions of himself, dormant around him.

"All right. It didn't work. What's happening now?"

Part of the answer came to him even before the ship spoke. The visible light sensors revealed face-on the disk of a barred galaxy. From the way that it filled the sky ahead, they were within a few tens of thousands of light-years-touching distance, in intergalactic terms.

Also, it was the galaxy. The ship's signal-receiving equipment showed the spiral arms filled with the glittering sparks of S-wave transmissions. The galaxy flamed with them, bright flickering points of blue and crimson. They had been color coded by the ship into type 1 and type 2-statistically different from each other, but equally mysterious.

If the ship was here, so close to the source of the signals, then a billion years or more must have passed since he was last conscious.

Why wasn't the ship answering his question? And then Drake realized that the ship had answered. A new block of information had been transferred, and his electronic consciousness was already processing it, thousands or millions of times faster than his old organic one. He knew, without being told . . .

The ship had remained for centuries at the focal point of the giant array. It had transmitted Drake as a superluminalsignal-not once but a hundred times and more. It had waited patiently for a return signal. Nothing came into the array but the same endless stream of unintelligible communications.

At last the ship had to make a difficult choice. If it left the array, all chance of receiving an intergalactic signal from Drake was lost. The ship would be forced to rely again on the simple S-wave detection system that it carried on board. On the other hand, to remain in one place and wait for a signal from Drake might take until the end of the universe.

Finally the ship abandoned the array and set out on its lonely billion-year journey across the intergalactic gulf. In doing so, it lost the ability to pick up superluminal signals from its destination until the target galaxy was close enough for the on-board system to operate.

How close?

This close. Close enough for the ship to employ a synthetic aperture optical system, able to produce visible wavelength pictures of surface detail on planets the size of Earth.

And now a new problem arose. It was baffling enough for the ship to know that it needed help. It had brought Drake to consciousness.

And because he would need direct access to all sensor inputs, and because in any case there was no planet within twenty thousand light-years where an embodied organic form might prove useful, the ship employed a different procedure. It did not embody the aroused intelligence, but resurrected it in electronic form.

Drake examined one of the planetary images as the ship drifted steadily on through space. The world was superficially Earth-like, sufficiently massive and far enough from its primary to hold an atmosphere. It should have had air of some kind, nitrogen or methane or carbon dioxide or, if it bore life, oxygen and water vapor. No trace of any showed up in the gas spectral analysis. The surface, unobscured by clouds or a shroud of air, was black rock. It looked like volcanic basalt that had flowed under high temperature before pooling and hardening to grotesque formations. There was no sign of surface water, no sign of life or surface artifacts. Orbiting the world like a swarm of lightning bugs were hundreds of objects too small to be seen with the imagers. However, from time to time a flash from one of them showed that it was transmitting, and the ship was receiving, an outgoing S-wave signal.

What was there to talk about in facilities that orbited long-dead worlds?

Drake tracked the destinations of the outgoing data bursts, and the ship offered their images at his command: world after world, scene after scene of charred devastation. Every planet was in ruins. Each was clearly lifeless.

"I have performed as complete a survey as possible from this distance." The ship's messages were clear and easy now that Drake knew how to listen to them. "The pattern repeats from one side of the galaxy to the other, from the outer rim to the central disk. Those worlds have in common what I have termed a type one superluminal message capability.

Compare them with the type two worlds."

Another sequence of planets was offered for Drake's inspection. From the ship's point of view, there were large differences. From a human point of view, one similarity overwhelmed every other factor: organic life was absent.

Drake examined a thousand type 2 planets where everything that humans had learned of physics, planetology, and biology suggested that life should have developed. The sun was an appropriate spectral type, surface temperature was in the right range, the planet had a low-eccentricity orbit, there was plenty of surface water, and a thick atmosphere of hydrogen, carbon dioxide, and nitrogen.

Life should have developed-must have developed. And it had developed. The proof was in the swarm of active devices around each world, emitting and receiving their bursts of S-wave signals. No one would install such a system without a purpose. Life had once been on all these worlds. And somehow life had been destroyed, not as spectacularly as on the type 1 worlds, but just as finally.

"The problem is one that we never anticipated." Was that the ship speaking, or Drake's own thoughts? The dividing line became blurred when they shared common storage and processing power. "We had always assumed that superluminal signal capability would be accompanied by a working technology. Now we find abundant S-wave capacity and nothing else. Do we wish to visit a galaxy that seems dead of organic life?"

"Is it safe to do so?"

The last thought was surely Drake's alone. His thoughts were moving again to old memories and offering an uneasysynthesis.

In an infinite universe, anything that can happen will happen.

He had been talking to himself, but his thoughts were no longer private.

"The universe is not infinite," the ship said. "It is finite in time both past and future, and it is finite but unbounded in space."

"All right. Change that to things that you never expected to happen, when you were long ago on a world far away, can happen if you wait long enough and go far enough."

He not only hadn't expected to see this-when he was young he had hardly taken notice of it. His interests revolved around music and Ana, and anything as dull as military policy or political strategy tended to be ignored. It was Ana, the social activist, who had educated him. He remembered one lazy October afternoon when they lay side by side in his little one-room apartment, with the Venetian blinds partly drawn and late sunlight casting elongated and distorted leaf shadows on the wall. Drake lay flat on his back. He didn't want to talk or think about anything and would have quite liked a nap. He found it easier to say nothing and pretend to listen, but he had got away with that for only a few minutes.

"You don't care, do you?" Ana punched him on the left shoulder and propped herself up on her elbow so that she could see his face and make sure that he wasn't going to sleep. "I'm telling you, it could happen again."

"Nah. Mutual Assured Destruction is a dead idea. And a dumb idea, too."

"It's worse than dumb, but I'm not sure it's dead. Brains and resources were wasted on it for two generations. Do you want to know why?"

Not really. But Drake said only, "Uh-huh."

"It kept on going because it was a big fat money tree, where corruption could thrive and contractors could get very rich. And because no matter what you do, for paranoid people more is never enough. If they build more weapons, or even if you just think that they might, you have to build more. They're as crazy as you are, so they have to build more, too; so you have to build more, so they have to build more, so you have to build more, so they have to build more, so you have to build more. ..."

She paused, rather to Drake's disappointment. The cadence of the repeated phrase was relaxing, and he would happily have nodded off listening to it. Instead he said, "I don't know why you're still worrying about all this. It's ancient history. MAD went away over twenty years ago, along with the Soviet Union."

She snuggled up against him and put her hand flat on his bare belly. "That proves how little you understand the military. I drank this stuff in with my mother's milk. Four of my uncles and five of my cousins are regular army or air force. You should hear the talk at family reunions. You did me a big favor. They can't stand your politics."

"I don't have any."

"That's almost worse. But they don't want you around, and that gives me an excuse to stay away. I'll never be able to thank you enough."

"You can thank me by letting me rest. Anyway, you shouldn't be thanking me. Thank Professor Bonvissuto. He got you the scholarship."

"I'll thank both of you. You know what Uncle Dan said? He's the air force colonel, the one from Baltimore who told you that the finest vocal group in the world was the Singing Sergeants, and that Wagner was a boring old weirdo."

"I remember him. Rossini said much the same- about Wagner, I mean, not the Singing Sergeants. He said Wagner had beautiful moments, but awful quarter hours. He also said that he couldn't judge Wagner's Lohengrin from a single hearing, and he certainly didn't intend hearing it a second time."

"Ideas in the military don't go away, ever, Uncle Dan says." Ana wasn't going to let Drake distract her with musical anecdotes. "Old ideas get put on the shelf, and when the right funding cycle comes around they're dusted off and proposed again as new. I don't believe a lot of what he tells me, but I believe that. Balance of terror didn't start with Mutual Assured Destruction. And it won't end with it. Bad ideas are still sitting there on the shelf."

And sometimes they sit on that shelf for an awfully long time before they finally achieve their potential."I do not think that I am following you," the ship said.

It was hardly surprising-Drake's private thoughts had not been intended for anyone else. They had hopped randomly between past and present, and they included personal references that were surely not in any general database.

Drake addressed his remarks directly to the ship's interface. "Mutual Assured Destruction is a very simple idea: I build huge weapons systems. So do you. Then you daren't attack me, because if you do, I'll attack you in return and you'll die, too." (He had killed Ana, and he had died, too. He had thought of his actions as Mutual Assured Survival. Did that make him any different from the Mutual Assured Destruction lunatics?) "So neither one of us dares to attack the other. It sounds as though it might work, but MAD has one fatal flaw. It produces an equilibrium between two groups, but it's an unstable equilibrium. One accident, or even a misunderstanding, and both sides will use their weapons.

They have to hit as hard as they can immediately, to neutralize as much of the other's firepower as they can. Just as bad, a third group with very few weapons can force a misunderstanding and make the two big powers fight each other, by faking an attack of one on the other. I think we are looking at the results when MAD is applied on a huge scale. I think it killed that whole galaxy."

"That cannot be true. Even now, I am detecting new superluminal messages. I cannot understand them, but it proves that intelligence continues to operate there."

"Intelligence of a sort. Sometimes if an idea is old enough, it can seem brand new. I ought to have known what was going on ages ago, as soon as you told me that there were two distinct types of signals coming from this galaxy, and that you were unable to interpret either of them. You said that any signal at all should be intelligible to you. But suppose it was designed not to be understood by anyone without a suitable key? Suppose both sides were employing ciphers, codes that the other could not break."

"Intentional obscurity. That is certainly possible. But what makes you so sure that the galaxy is dead? How can that be true, and the technology still be working?"

Drake realized that he could explain even that. His mind had thrown at him an image of a long-ago performance of Haydn's Farewell Symphony, of a conductor facing a group of players. In front of each stood a lighted candle. One by one, each musician finished his or her own orchestral part, snuffed out the candle, and left the stage. Finally the whole orchestra was gone. The conductor stood alone in darkness.

The ship was unlikely to benefit much from that thought. "Let me tell you what happened on Earth," Drake said, "in the years just after I was born. Two great powers had been busy building up their nuclear weapons. The chance of all-out war seemed very high. That war, if it happened, would be short. A couple of hours and it would be all over.

Missiles over the pole could be launched to reach any target within thirty minutes. The military on one side-our side, people would say, though I never thought of it as my side-decided that they must keep some kind of communications system working, even after the main war was over. They imagined a space-based command post, a whole constellation of special satellites in orbit around the Earth. The spacecraft would be completely operated by computers, and they would form a kind of central nervous system for all fighting, no matter when it happened. The system was called MILSTAR, for Military Strategic, Tactical, and Relay system, and it was supposed to be able to function even after the main spasm of war was over. The military planners didn't intend for MILSTAR to help with civilian reconstruction.

That wasn't its job. They wanted it to handle military communications-and to be able to support fighting again, if necessary, months or years later. They wanted MIL-STAR ready to fight another war. It was designed to function even if all the surface command structures had been obliterated. It was supposed to be able to call on robot weaponry, whether or not there were humans around."

The image came again. The conductor stood facing a full complement of players. As the military .powers on land, sea, and air were snuffed out by enemy action, MILSTAR continued, organizing and optimizing resources that became smaller every second. Finally, the stage held nothing but orchestral desks and empty instrument cases. The conductor waved his baton over a vanished army of players. MILSTAR floated serenely on through space, its communications system in full working order and ready to shape a second symphony of Armageddon.

"The MILSTAR satellites had to be very sophisticated. They needed a long operating lifetime. They had to be mobile, to avoid direct missile attack; durable, to operate for years without a single human mind to direct them; robust, to survive electromagnetic pulse effects and near misses; and smart, able to talk easily to each other using a variety of encrypted signals, so that the enemy could never crack the global communications network.

"It was a highly secret project. It had to be. That was why it was able to obtain huge funding for a long time, even though anyone who looked at it objectively could see why it wouldn't work. It needed tens of millions of computer instructions, lines of program code that could only be tested when the actual war was declared. It assumed a static world order, with a single well-defined enemy. It bypassed every civilian chain of command. Worst of all, it assumedthat one side or the other could win an all-out nuclear war, and be all set to fight again. No mention of hundreds of millions of casualties, or disabled food and water and sewage and transportation systems, or a totally collapsed economy that couldn't pay ten cents for a military budget.

"Well, we were lucky. MILSTAR came out from behind its veil of secrecy, little by little. That doomed it. It couldn't stand the sunlight. Finally, after years and years of staggering along when no one really believed in it but kept it going as a source of jobs and a political pork barrel, the money was cut off and the development ended. MILSTAR never became a working system -on Earth. But something like it was developed, and is still in operation"-Drake indicated the galaxy ahead of the ship-"there."

Drake had been carried away, in time and space and in a depth of feeling lost to him for aeons. He knew he had spoken for Ana, more than for himself. Those had been her voiced fears, her indignation, her relief at an earthly doom avoided.

He also realized, for the first time, that existence in a purely electronic form could admit emotion and passion and longing.

The ship had absorbed the facts of his message, if not its intensity. "So although an S-wave signal system exists in that galaxy," it said, "the original creators and owners are long vanished. Therefore no moral or practical impediment exists to our taking over its use. We should find it possible to inhibit the encryption system. As soon as we have done that, and our own type of S-wave signals can be sent and received-"

"We can't do that."

"I believe that I possess the necessary analytical capabilities, even though you may not be aware of them."

"That's not the problem. The problem is in going there." Drake again indicated the galaxy ahead of them.

"We are only twenty-one thousand light-years away. We have traveled forty thousand times that distance already, without difficulty. The remaining journey is negligible."

"No. It's the place where we can expect trouble. Look at them." Drake displayed an array of blackened and silent worlds for the ship's attention. "We can't say what did this, and for all we know it may still be working. Maybe it's waiting for something new that it can hit. The weapons ran out of targets. We don't know that they ran out of anything else. Just because a galaxy is dead of life doesn't mean it's safe to go there."

"Then I request that you propose an alternative." The ship turned its imaging equipment, swinging slowly from the island of matter ahead to the great ocean of space that surrounded it. "The next nearest galaxy is two and a quarter million light-years away. It showed no evidence of S-wave transmission. Do you suggest that we change to it as our target? I am ready to follow your instructions."

And that was the devil of it. There was no better alternative. No other galaxy, in a search that stretched halfway across time, had displayed superluminal signals. It was a poor moment to decide that the ship had left the big detection system, laboriously constructed over so many years, prematurely. But it was true. The smart thing would have been to survey every galaxy in the universe for S-wave transmissions, before rushing off to tackle the enigma of the one that lay ahead.

It was Drake's fault. He should have thought harder and longer before he acted. The price of mindless action was high: they had to return to their detection system, a billion years away, and follow that with another interminable search.

That was the price. But he was not willing to pay it.

Surely something could be done with the facilities that lay ahead of them, so temptingly close? Compared with the other option, twenty thousand light-years was like stepping to the house next door. He knew, with absolute certainty, that a full superluminal capability existed here, in perfect working order. Nothing like it might be found again before the universe itself came to a close.

As the field of view of the ship's sensors performed its steady turn in space, Drake watched the grand sweep of the galaxies. They had not changed. He had changed. When had he lost his will and daring? When had he become so cautious?

Long ago, without a second thought, he had risked everything. Now, no matter what he did, he would be risking less than everything. Other versions of him surely still existed, even if they happened to be at the far edge of the universe.

They did not know that he existed-they would think that he had died fifteen billion years ago, when the ship was swallowed by the caesura. But what of that? They should still be there. Did he have anything to lose, if now he risked the dark menace ahead?"Aye, but to die, and go we know not where ..."

Was that all it was? Simple fear of death?

"Are we still heading for the galaxy?"

"Yes. We have not changed our course."

"Then forget the alternative. Hold our path. Take us to the nearest world where you are detecting a source of S-wave messages."

There are many events in the womb of time which will be delivered.

And how long since he had thought of that? It was time to take a chance, and test the kindness of reality.

Taking a chance on one thing did not mean abandoning caution in everything else.

Drake elected to remain conscious, though not embodied, through the whole slow approach to the galaxy. The ship's speed had to be subluminal. Meanwhile, the S-wave messages flashed and flickered ahead from spiral arm to spiral arm, as enigmatic as ever. At Drake's suggestion, the ship's brain assumed that the messages were deliberately encrypted and tried to decipher them. The effort consumed the bulk of the ship's computation powers for twelve thousand years.

There was no useful result for either type 1 or type 2 messages.

While this was going on, Drake constantly monitored the galaxy ahead. He had no idea of the range of weapons that remained there. At any moment, the ship's approach might be detected, and an alien force could reach out to consume them. He was ready to power the ship down totally and hope that silence would end the attack, or if that failed to turn the ship around and try to outrun the destruction.

The thirteenth millennium brought the change. It occurred while Drake and the ship were analyzing the comparative freedoms and restrictions of their two mentalities.

"What would you have done, in a similar situation?" The ship was dissatisfied with its own performance.

"Assuming that I were a ship, with your history and your inorganic intelligence? The first thing I would do, after Drake Merlin insisted on being sent as a superluminal signal to this galaxy, is tell myself that embodied humans tend to be impulsive and make decisions too quickly. We evolved that way, because the old human body rarely lasted a century.

We were always in a hurry, we had to be. So as a ship I would have spent a long time evaluating my own possible actions. Then I hope I would have asked what could be done at the S-wave detection structure we built and nowhere else. When all those things were done, I would have headed this way."

"And what would you have done as a human in the same situation?"

"If I could see no possible further use for my existence-"

Drake's comments on suicide, an idea alien to the ship's intelligence, were interrupted.

A-W-A-W-A-W-A-W-A-W-A-W-A-. The ship's S-wave detector screeched and warbled in overload as a message blared into it.

A-W-A-W-A-W-A-W-A-W-A-W-A-W-A-W-A-.