Seldon wondered whether to take another bite. "You mean that as long as I stay on Trantor-"

  Hummin made a hushing motion with his lips. "Don't give anyone the impression that you're used to better. There are places on Trantor where to be identified as an aristocrat is worse than being identified as an Outworlder. The food won't be so bad everywhere,

  I assure you. These wayside places have a reputation for low quality. If you can stomach that sandwich, you'll be able to eat anywhere on Trantor. And it won't hurt you. It's not decayed or bad or anything like that. It just has a harsh, strong taste and, honestly, you may grow accustomed to it. I've met Trantorians who spit out honest food and say it lacks that homegrown tang."

  "Do they grow much food on Trantor?" asked Seldon. A quick side glance showed him there was no one seated in the immediate vicinity and he spoke quietly. "I've always heard it takes twenty surrounding worlds to supply the hundreds of freight ships required to feed Trantor every day."

  "I know. And hundreds to carry off the load of wastes. And if you want to make the story really good, you say that the same freight ships carry food one way and waste the other. It's true that we import considerable quantities of food, but that's mostly luxury items. And we export considerable waste, carefully treated into inoffensiveness, as important organic fertilizer-every bit as important to other worlds as the food is to us. But that's only a small fraction of the whole."

  "It is?"

  "Yes. In addition to fish in the sea, there are gardens and truck farms everywhere. And fruit trees and poultry and rabbits and vast microorganism farms-usually called yeast farms, though the yeast makes up a minority of the growths. And our wastes are mostly used right here at home to maintain all that growth. In fact, in many ways Trantor is very much like an enormous and overgrown space settlement. Have you ever visited one of those?"

  "Indeed I have."

  "Space settlements are essentially enclosed cities, with everything artificially cycled, with artificial ventilation, artificial day and night, and so on. Trantor is different only in that even the largest space settlement has a population of only ten million and Trantor has four thousand times that. Of course, we have real gravity. And no space settlement can match us in our microfoods. We have yeast vats, fungal mats, and algae ponds vast beyond the imagination. And we are strong on artificial flavoring, added with no light hand. That's what gives the taste to what you're eating."

  Seldon had gotten through most of his sandwich and found it not as offensive as the first bite had been. "And it won't affect me?"

  "It does hit the intestinal flora and every once in a while it afflicts some poor Outworlder with diarrhea, but that's rare, and you harden even to that quickly. Still, drink your milkshake, which you probably won't like. It contains an antidiarrhetic that should keep you safe, even if you tend to be sensitive to such things."

  Seldon said querulously, "Don't talk about it, Hummin. A person can be suggestible to such things."

  "Finish the milkshake and forget the suggestibility."

  They finished the rest of their meal in silence and soon were on their way again.

  13.

  They were now racing rapidly through the tunnel once more. Seldon decided to give voice to the question that had been nagging at him for the last hour or so.

  "Why do you say the Galactic Empire is dying?"

  Hummin turned to look at Seldon again. "As a journalist, I have statistics poured into me from all sides till they're squeezing out of my ears. And I'm allowed to publish very little of it. Trantor's population is decreasing. Twenty-five years ago, it stood at almost forty-five billion.

  "Partly, this decrease is because of a decline in the birthrate. To be sure, Trantor never has had a high birthrate. If you'll look about you when you're traveling on Trantor, you won't encounter very many children, considering the enormous population. But just the same it's declining. Then too there is emigration. People are leaving Trantor in greater numbers than are arriving."

  "Considering its large population," said Seldon, "that's not surprising."

  "But it's unusual just the same because it hasn't happened before. Again, all over the Galaxy trade is stagnating. People think that because there are no rebellions at the moment and because things are quiet that all is well and that the difficulties of the past few centuries are over. However, political infighting, rebellions, and unrest are all signs of a certain vitality too. But now there's a general weariness. It's quiet, not because people are satisfied and prosperous, but because they're tired and have given up."

  "Oh, I don't know," said Seldon dubiously.

  "I do. And the antigrav phenomenon we've talked about is another case in point. We have a few gravitic lifts in operation, but new ones aren't being constructed. It's an unprofitable venture and there seems no interest in trying to make it profitable. The rate of technological advance has been slowing for centuries and is down to a crawl now. In some cases, it has stopped altogether. Isn't this something you've noticed? After all, you're a mathematician."

  "I can't say I've given the matter any thought."

  "No one does. It's accepted. Scientists are very good these days at saying that things are impossible, impractical, useless. They condemn any speculation at once. You, for instance-What do you think of psychohistory? It is theoretically interesting, but it is useless in any practical sense. Am I right?"

  "Yes and no," said Seldon, annoyed. "It is useless in any practical sense, but not because my sense of adventure has decayed, I assure you. It really it useless."

  "That, at least," said Hummin with a trace of sarcasm, "is your impression in this atmosphere of decay in which all the Empire lives."

  "This atmosphere of decay," said Seldon angrily, "is your impression. Is it possible that you are wrong?"

  Hummin stopped and for a moment appeared thoughtful. Then he said, "Yes, I might be wrong. I am speaking only from intuition, from guesses. What I need is a working technique of psychohistory. "

  Seldon shrugged and did not take the bait. He said, "I don't have such a technique to give you. -But suppose you're right. Suppose the Empire it running down and will eventually stop and fall apart. The human species will still exist."

  "Under what conditions, man? For nearly twelve thousand years, Trantor, under strong rulers, has largely kept the peace. There've been interruptions to that-rebellions, localized civil wars, tragedy in plenty-but, on the whole and over large areas, there has been peace. Why is Helicon so pro-Imperium? Your world, I mean. Because it is small and would be devoured by its neighbors were it not that the Empire keeps it secure."

  "Are you predicting universal war and anarchy if the Empire fails?"

  "Of course. I'm not fond of the Emperor or of the Imperial institutions in general, but I don't have any substitute for it. I don't know what else will keep the peace and I'm not ready to let go until I have something else in hand."

  Seldon said, "You talk as though you are in control of the Galaxy. You are not ready to let go? You must have something else in hand? Who are you to talk so?"

  "I'm speaking generally, figuratively," said Hummin. "I'm not worried about Chetter Hummin personally. It might be said that the Empire will last my time; it might even show signs of improvement in my time. Declines don't follow a straight-line path. It may be a thousand years before the final crash and you might well imagine I would be dead then and, certainly, I will leave no descendants. As far as women are concerned, I have nothing but the occasional casual attachment and I have no children and intend to have none. I have given no hostages to fortune. -I looked you up after your talk, Seldon. You have no children either."

  "I have parents and two brothers, but no children." He smiled rather weakly. "I was very attached to a woman at one time, but it seemed to her that I was attached more to my mathematics."

  "Were you?"

  "It didn't seem so to me, but it seemed so to her. So she left."

  "And you have had no one since?"

>   "No. I remember the pain too clearly as yet."

  "Well then, it might seem we could both wait out the matter and leave it to other people, well after our time, to suffer. I might have been willing to accept that earlier, but no longer. For now I have a tool; I am in command."

  "What's your tool?" asked Seldon, already knowing the answer.

  "You!" said Hummin.

  And because Seldon had known what Hummin would say, he wasted no time in being shocked or astonished. He simply shook his head and said, "You are quite wrong. I am no tool fit for use."

  "Why not?"

  Seldon sighed. "How often must I repeat it? Psychohistory is not a practical study. The difficulty is fundamental. All the space and time of the Universe would not suffice to work out the necessary problems."

  "Are you certain of that?"

  "Unfortunately, yes."

  "There's no question of your working out the entire future of the Galactic Empire, you know. You needn't trace out in detail the workings of every human being or even of every world. There are merely terrain questions you must answer: Will the Galactic Empire crash and, if so, when? What will be the condition of humanity afterward? Can anything be done to prevent the crash or to ameliorate conditions afterward? These are comparatively simple questions, it seems to me."

  Seldon shook his head and smiled sadly. "The history of mathematics is full of simple questions that had only the most complicated of answers-or none ac all."

  "Is there nothing to be done? I can see that the Empire is falling, but I can't prove it. All my conclusions are subjective and I cannot show that I am not mistaken. Because the view is a seriously unsettling one, people would prefer not to believe my subjective conclusion and nothing will be done to prevent the Fall or even to cushion it. You could prove the coming Fall or, for that matter, disprove it."

  "But that is exactly what I cannot do. I can't find you proof where none exists. I can't make a mathematical system practical when it isn't. I can't find you two even numbers that will yield an odd number as a sum, no matter how vitally your all the Galaxy -may need that odd number."

  Hummin said, "Well then, you're pare of the decay. You're ready to accept failure."

  "What choice have I?"

  "Can't you try? However useless the effort may seem to you to be, have you anything better to do with your life? Have you some worthier goal? Have you a purpose that will justify you in your own eyes to some greater extent?"

  Seldon's eyes blinked rapidly. "Millions of worlds. Billions of cultures. Quadrillions of people. Decillions of interrelationships. -And you want me to reduce it to order."

  "No, I want you to try. For the sake of those millions of worlds, billions of cultures, and quadrillions of people. Not for the Emperor. Not for Demerzel. For humanity."

  "I will fail," said Seldon.

  "Then we will be no worse off. Will you try?"

  And against his will and not knowing why, Seldon heard himself say, "I will try." And the course of his life was set.

  14. The journey came to its end and the air-taxi moved into a much larger lot than the one at which they had eaten. (Seldom still remembered the taste of the sandwich and made a wry face.)

  Hummin turned in his taxi and came back, placing his credit slip in a small pocket on the inner surface of his shirt. He said, "You're completely safe here from anything outright and open. This is the Streeling Sector."

  "Streeling?"

  "It's named for someone who first opened up the area to settlement, I imagine. Most of the sectors are named for someone or other, which means that most of the names are ugly and some are hard to pronounce. Just the same, if you try to have the inhabitants here change Streeling to Sweetsmell or something like that, you'll have a fight on your hands."

  "Of course," said Seldon, sniffing loudly, "it isn't exactly Sweetsmell."

  "Hardly anywhere in Trantor is, but you'll get used to it."

  "I'm glad we're here," said Seldon. "Not that I like it, but I got quite tired sitting in the taxi. Getting around Trantor must be a horror. Back on Helicon, we can get from any one place to any other by air, in far less time than it took us to travel less than two thousand kilometers here."

  "We have air-jets too."

  "But in that case-"

  "I could arrange an air-taxi ride more or less anonymously. It would have been much more difficult with an air-jet. And regardless of how safe it is here, I'd feel better if Demerzel didn't know exactly where you were. -As a matter of fact, we're not done yet. We're going to take the Expressway for the final stage."

  Seldon knew the expression. "One of those open monorails moving on an electromagnetic field, right?"

  "Right."

  "We don't have them on Helicon. Actually, we don't need them there. I rode on an Expressway the first day I was on Tmntor. It took me from the airport to the hotel. It was rather a novelty, but if I were to use it all the time, I imagine the noise and crowds would become overpowering."

  Hummin looked amused. "Did you get lost?"

  "No, the signs were useful. There was trouble getting on and off, but I was helped. Everyone could tell I was an Outworlder by my clothes, I now realize. They seemed eager to help, though; I guess because it was amusing to watching me hesitate and stumble."

  "As an expert in Expressway travel by now, you will neither hesitate nor stumble." Hummin said it pleasantly enough, though there was a slight twitch to the corners of his mouth. "Come on, then."

  They sauntered leisurely along the walkway, which was lit to the extent one might expect of an overcast day and that brightened now and then as though the sun occasionally broke through the clouds. Automatically, Seldon looked upward to see if that were indeed the case, but the "sky" above was blankly luminous.

  Hummin saw this and said, "This change in brightness seems too suit the human psyche. There are days when the street seems to be in bright sunlight and days when it is rather darker than it is now."

  "But no rain or snow?"

  "Or hail or sleet. No. Nor high humidity nor bitter cold. Trantor has its points, Seldon, even now."

  There were people walking in both directions and there were a considerable number of young people and also some children accompanying the adults, despite what Hummin had said about the birthrate. All seemed reasonably prosperous and reputable. The two sexes were equally represented and the clothing was distinctly more subdued than it had been in the Imperial Sector. His own costume, as chosen by Hummin, fit right in. Very few were wearing hats and Seldon thankfully removed his own and swung it at his side.

  There was no deep abyss separating the two sides of the walkway and as Hummin had predicted in the Imperial Sector, they were walking at what seemed to be ground level. There were no vehicles either and Seldon pointed this out to Hummin.

  Hummin said, "There are quite a number of them in the Imperial Sector because they're used by officials. Elsewhere, private vehicles are rare and those that are used have separate tunnels reserved for them. Their use is not really necessary, since we have Expressways and, for shorter distances, moving corridors. For still shorter distances, we have walkways and we can use our legs."

  Seldon heard occasional muted sighs and creaks and saw, some distance off, the endless ,passing of Expressway cars.

  "There it is," he said, pointing.

  "I know, but let us move on to a boarding station. There are more cars there and it is easier to get on."

  Once they were safely ensconced in an Expressway car, Seldon turned to Hummin and said, "What amazes me is how quiet the Expressways are. I realize that they are mass-propelled by an electromagnetic field, but it seems quiet even for that." He listened to the occasional metallic groan as the car they were on shifted against its neighbors.

  "Yes, it's a marvelous network," said Hummin, "but you don't see is at its peak. When I was younger, it was quieter than is is now and there are those who say that there wasn't as much as a whisper fifty years agothough I suppose we might make allow
ance for the idealization of nostalgia."

  "Why isn't it that way now?"

  "Because it isn't maintained properly. I told you about decay."

  Seldon frowned. "Surely, people don't sit around and say, 'We're decaying. Let's let the Expressways fall apart.' "

  "No, they don't. It's not a purposeful thing. Bad spots are patched, decrepit coaches refurbished, magnets replaced. However, it's done in more slapdash fashion, more carelessly, and at greater intervals. There just aren't enough credits available."

  "Where have the credits gone?"

  "Into other things. We've had centuries of unrest. The navy is much larger and many times more expensive than it once was. The armed forces are much better-paid, in order to keep them quiet. Unrest, revolts, and minor blazes of civil war all take their toll."

  "But it's been quiet under Cleon. And we've had fifty years of peace."

  "Yes, but soldiers who are well-paid would resent having that pay reduced just because there is peace. Admirals resist mothballing ships and having themselves reduced in rank simply because there is less for them to do. So the credits still go-unproductively -to the armed forces and vital areas of the social good are allowed to deteriorate. That's what I call decay. Don't you? Don't you chink that eventually you would fit that sort of view into your psychohistorical notions?"

  Seldon stirred uneasily. Then he said, "Where are we going, by the way?"

  "Streeling University."

  "Ah, chat's why the sector's name was familiar. I've heard of the University."

  "I'm not surprised. Trantor has nearly a hundred thousand institutions of higher learning and Streeling is one of the thousand or so at the top of the heap."

  "Will I be staying there?"

  "For a while. University campuses are unbreathable sanctuaries, by and large. You will be safe there."

  "But will I be welcome there?"

  "Why not? It's hard to find a good mathematician these days. They might be able to use you. And you might be able to use them coo-tend for more than just a hiding place."