Golan," said Pelorat. "Does it bother you if I watch?""Not at all, Janov," said Trevize.
"If I ask questions?""Go ahead."Pelorat said, "What are you doing?"Trevize took his eyes off the viewscreen. "I've got to measure thedistance of each star that seems to be near the Forbidden World onthe screen, so that I can determine how near they really are. Theirgravitational fields must be known and for that I need mass anddistance. Without that knowledge, one can't be sure of a clean Jump.""How do you do that?""Well, each star I see has its co-ordinates in the computer's memorybanks and these can be converted into co-ordinates on the Comporelliansystem. That can, in turn, be slightly corrected for the actual positionof the For Star in space relative to Comporellon's sun, and that givesme the distance of each. Those red dwarfs all look quite near theForbidden World on the screen, but some might be much closer and somemuch farther. We need their three-dimensional position, you see."Pelorat nodded, and said, "And you already have the co-ordinates ofthe Forbidden World ""Yes, but that's not enough. I need the distances of the otherstars to within a percent or so. Their gravitational intensity in theneighborhood of the Forbidden World is so small that a slight errormakes no perceptible difference. The sun about which the Forbidden Worldrevolves or might revolve possessss an enormously intensegravitational field in the neighborhood of the Forbidden World and Imust know its distance with perhaps a thousand times the accuracy ofthat of the other stars. The co-ordinatss alone won't do.""Then what do you do?""I measure the apparent separation of the Forbidden World or,rather, its star from three nearby stars which are so dim it takesconsiderable magnification to make them out at all. Presumably, thosethree are very far away. We then keep one of those three stars centered onthe screen and Jump a tenth of a parsec in a direction at right angles tothe line of vision to the Forbidden World. We can do that safely enougheven without knowing distances to comparatively far-off stars.
"The reference star which is centered would still be centered afterthe Jump. The two other dim stars, if all three are truly very distant,do not change their positions measurably. The Forbidden World, however,is close enough to change its apparent position in parallactic shift. Fromthe size of the shift, we can determine its distance. If I want to makedoubly certain, I choose three other stars and try again."Pelorat said, "How long doss all that take?""Not very long. The computer doss the heavy work. I just tell it whatto do. What really takes the time is that I have to study the resultsand make sure they look right and that my instructions aren't at faultsomehow. If I were one of those daredevils with utter faith in themselvesand the computer, it could all be done in a few minutes."Pelorat said, "It's really astonishing. Think how much the computerdoes for us.""I think of it all the time.""What would you do without it?""What would I do without a gravitic ship? What would I do withoutmy astronautic training? What would I do without twenty thousandyears of hyperspatial technology behind me? The fact is that I'mmyself here now. Suppose weeeere to imagine ourselves twentythousand additional years into the future. What technological marvelswould we have to be grateful for? Or might it be that twenty thousandyears hence humanity would not exist?""Scarcely that," said Pelorat. "Scarcely not exist. Even if wedon't become part of Galaxia, we would still have psychohistory toguide us."Trevize turned in his chair, releasing his handhold on thecomputer. "Let it work out distances," he said, "and let it check thematter a number of times. There's no hurry."He looked quizzically at Pelorat, and said, "Psychohistory! You know,Janov, twice that subject came up on Comporellon, and twice it wasdescribed as a superstition. I said so once, and then Deniador said italso. After all, how can you define psychohistory but as a superstitionof the Foundation? Isn't it a belief without proof or evidence? What doyou think, Janov? It's more your field than mine."Pelorat said, "Why do you say there's no evidence, Golan? Thesimulacrum of Hari Seldon has appeared in the Time Vault many times andhas discussed events as they happened. He could not have known whatthose events would be, in his time, had he not been able to predictthem psychohistorically."Trevize nodded. "That sounds impressive. He was wrong about theMule, but even allowing for that, it's impressive. Still, it has anuncomfortable magical feel to it. Any conjurer can do tricks.""No conjurer could predict centuries into the future.""No conjurer could really do what he makes you think he does.""Come, Golan. I can't think of any trick that would allow me topredict what will happen five centuries from now.""Nor can you think of a trick that will allow a conjurer to readthe contents of a message hidden in a pseudo-tesseract on an unmannedorbiting satellite. Just the same, I've seen a conjurer do it. Has itever occurred to you that the Time Capsule, along with the Hari Seldonsimulacrum, may be rigged by the government?"Pelorat looked as though he were revolted by the suggestion. "Theywouldn't do that."Trevize made a scornful sound.
Pelorat said, "And they'd be caught if they tried.""I'm not at all sure of that. The point is, though, that we don'tknow how psychohistory works at all.""I don't know how that computer works, but I know it works.""That's because others know how it works. How would it be if noone knew how it worked? Then, if it stopped working for any reason, wewould be helpless to do anything about it. And if psychohistory suddenlystopped working ""The Second Foundationers know the workings of psychohistory.""How do you know that, Janov?""So it is said.""Anything can be said. Ah, we have the distance of theForbidden World's star, and, I hope, very accurately. Let's considerthe figures."He stared at them for a long time, his lips moving occasionally,as though he were doing some rough calculations in his head. Finally,he said, without lifting his eyes, "What's Bliss doing?""Sleeping, old chap," said Pelorat. Then, defensively, "Sheneeds sleep, Golan. Maintaining herself as part of Gaiaacross hyperspace is energy-consuming.""I suppose so," said Trevize, and turned back to the computer. Heplaced his hands on the desk and muttered, "I'll let it go in severalJumps and have it recheck each time." Then he withdrew them againand said, "I'm serious, Janov. What do you know aboutpsychohistory?"Pelorat looked taken aback. "Nothing. Being a historian,which I am, after a fashion, is worlds different from being apsychohistorian. Of course, I know the two fundamental basics ofpsychohistory, but everyone knows that.""Even I do. The first requirement is that the number of human beingsinvolved must be large enough to make statistical treatment valid. Buthow large is `large enough'?"Pelorat said, "The latest estimate of the Galactic populationis something like ten quadrillion, and that's probably anunderestimate. Surely, that's large enough.""How do you know?""Because psychohistory does work, Golan. No matter howyou chop logic, it does work.""And the second requirement," said Trevize, "is that human beingsnot be aware of psychohistory, so that the knowledge does not skew theirreactions. But they are aware of psychohistory.""Only of its bare existence, old chap. That's not whatcounts. The second requirement is that human beings not be awareof the predictions of psychohistory and that they arenot except that the Second Foundationers are supposed to be awareof them, but they're a special case.""And upon those two requirements alone , the science ofpsychohistory has been developed. That's hard to believe.""Not out of those two requirements alone, " said Pelorat. "Thereare advanced mathematics and elaborate statistical methods. Thestory is if you want tradition that Hari Seldon devisedpsychohistory by modeling it upon the kinetic theory of gases. Each atomor molecule in a gas moves randomly so that we can't know the position orvelocity of any one of them. Nevertheless, using statistics, we can workout the rules governing their overall behavior with great precision. Inthe same way, Seldon intended to work out the overall behavior of humansocieties even though the solutions would not apply to the behavior ofindividual human beings.""Perhaps, but human beings aren't atoms.""True," said Pelorat. "A human being has consciousness and his behavioris sufficiently complicated to make it appear to be free will. How Seldonhandled that I haven't any idea, and I'm sure I couldn't understandit even if someone who knew tried to explain it to me but hedid it."Trevize said, "And the whole thing depends on dealing with people whoare both numerous and unaware. Doesn't that seem to you a quicksandishfoundation on which to build an enormous mathematical structure? Ifthose requirements are not truly met, then everything collapses.""But since the Plan hasn't collapsed ""Or, if the requirements are not exactly false or inadequate butsimply weaker than they should be, psychohistory might work adequatelyfor centuries and then, upon reaching some particular crisis, wouldcollapse as it did temporarily in the time of the Mule. Orwhat if there is a third requirement?""What third requirement?" asked Pelorat, frowning slightly.
"I don't know," said Trevize. "An argument may seem thoroughlylogical and elegant and yet contain unexpressed assumptions. Maybe thethird requirement is an assumption so taken for granted that no one everthinks of mentioning it.""An assumption that is so taken for granted is usually valid enough,or it wouldn't be so taken for granted."Trevize snorted. "If you knew scientific history as well as you knowtraditional history, Janov, you would know how wrong that is. ButI see that we are now in the neighborhood of the sun of the ForbiddenWorld."And, indeed, centered on the screen, was a bright star one sobright that the screen automatically filtered its light to the pointwhere all other stars were washed out.
32Facilities for washing and for personal hygiene on boardthe Far Star were compact, and the use of water was always held to areasonable minimum to avoid overloading the recycling facilities. BothPelorat and Bliss had been sternly reminded of this by Trevize.
Even so, Bliss maintained an air of freshness at all times and herdark, long hair could be counted on to be glossy, her fingernails tosparkle.
She walked into the pilot-room and said, "There you are!"Trevize looked up and said, "No need for surprise. We could scarcelyhave left the ship, and a thirty-second search would be bound touncover us inside the ship, even if you couldn't detect our presencementally."Bliss said, "The expression was purely a form of greeting and notmeant to be taken literally, as you well know. Where are we? Anddon't say, `In the pilot-room.'""Bliss dear," said Pelorat, holding out one arm, "we're at the outerregions of the planetary system of the nearest of the three ForbiddenWorlds."She walked to his side, placing her hand lightly on his shoulder,while his arm moved about her waist. She said, "It can't be veryForbidden. Nothing has stopped us."Trevize said, "It is only Forbidden because Comporellon and the otherworlds of the second wave of settlement have voluntarily placed the worldsof the first wave the Spacers out of bounds. If we ourselvesdon't feel bound by that voluntary agreement, what is to stop us?""The Spacers, if any are left, might have voluntarily placed theworlds of the second wave out of bounds, too. Just because we don't mindintruding upon them doesn't mean that they don't mind it.""True," said Trevize, "If they exist. But so far we don't even knowif any planet exists for them to live on. So far, all we see are theusual gas giants. Two of them, and not particularly large ones."Pelorat said hastily, "But that doesn't mean the Spacer worlddoesn't exist. Any habitable world would be much closer to the sunand much smaller and very hard to detect in the solar glare from thisdistance. We'll have to micro-Jump inward to detect such a planet." Heseemed rather proud to be speaking like a seasoned space traveler.
"In that case," said Bliss, "why aren't we moving inward?""Not just yet," said Trevize. "I'm having the computer check as faras it can for any sign of an artificial structure. We'll move inwardby stages a dozen, if necessary checking at each stage. Idon't want to be trapped this time as we were when we first approachedGaia. Remember, Janov?""Traps like that could catch us every day. The one at Gaia broughtme Bliss." Pelorat gazed at her fondly.
Trevize grinned. "Are you hoping for a new Bliss every day?"Pelorat looked hurt, and Bliss said, with a trace of annoyance,"My good chap or whatever it is that Pel insists on callingyou you might as well move in more quickly. While I am with you,you will not be trapped.""The power of Gaia?""To detect the presence of other minds? Certainly.""Are you sure you are strong enough, Bliss? I gather you must sleepquite a bit to regain strength expended at maintaining contact with themain body of Gaia. How far can I rely on the perhaps narrow limits ofyour abilities at this distance from the source?"Bliss flushed. "The strength of the connection is ample."Trevize said, "Don't be offended. I'm simply asking. Don't yousee this as a disadvantage of being Gaia? I am not Gaia. I am a completeand independent individual. That means I can travel as far as I wish frommy world and my people, and remain Golan Trevize. What powers I have,and such as they are, I continue to have, and they remain whereverI go. If I were alone in space, parsecs away from any human being,and unable, for some reason, to communicate with anyone in any way,or even to see the spark of a single star in the sky, I would be andremain Golan Trevize. I might not be able to survive, and I might die,but I would die Golan Trevize."Bliss said, "Alone in space and far from all others, you would beunable to call on the help of your fellows, on their different talentsand knowledge. Alone, as an isolated individual, you would be sadlydiminished as compared with youself as part of an integrated society. Youknow that."Trevize said, "There would nevertheless not be the same diminution asin your case. There is a bond between you and Gaia that is far strongerthan the one between me and my society, and that bond stretches throughhyperspace and requires energy for maintenance, so that you must gasp,mentally, with the effort, and feel yourself to be a diminished entityfar more than I must."Bliss's young face set hard and, for a moment, she looked young nomore or, rather, she appeared ageless more Gaia than Bliss, asthough to refute Trevize's contention. She said, "Even if everything yousay is so, Golan Trevize that is, was, and will be, that cannotperhaps be less, but certainly cannot be more even if everythingyou say is so, do you expect there is no price to be paid for a benefitgained? Is it not better to be a warm-blooded creature such as yourselfthan a cold-blooded creature such as a fish, or whatever?"Pelorat said, "Tortoises are cold-blooded. Terminus doesn't have any,but some worlds do. They are shelled creatures, very slow-moving butlong-living.""Well, then, isn't it better to be a human being than a tortoise; tomove quickly whatever the temperature, rather than slowly? Isn't it betterto support high-energy activities, quickly contracting muscles, quicklyworking nerve fibers, intense and long-sustained thought than tocreep slowly, and sense gradually, and have only a blurred awareness ofthe immediate surroundings? Isn't it?""Granted," said Trevize. "It is. What of it?""Well, don't you know you must pay for warm-bloodedness? To maintainyour temperature above that of your surroundings, you must expend energyfar more wastefully than a tortoise must. You must be eating almostconstantly so that you can pour energy into your body as quickly as itleaks out. You would starve far more quickly than a tortoise would,and die more quickly, too. Would you rather be a tortoise, and livemore slowly and longer? Or would you rather pay the price and be aquick-moving, quick-sensing, thinking organism?""Is this a true analogy, Bliss?""No, Trevize, for the situation with Gaia is more favorable. We don'texpend unusual quantities of energy when we are compactly together. It isonly when part of Gaia is at hyperspatial distances from the rest of Gaiathat energy expenditure rises. And remember that what you have votedfor is not merely a larger Gaia, not just a larger individual world. Youhave decided for Galaxia, for a vast complex of worlds. Anywhere in theGalaxy, you will be part of Galaxia and you will be closely surroundedby parts of something that extends from each interstellar atom to thecentral black hole. It would then require small amounts of energy toremain a whole. No part would be at any great distance from all otherparts. It is all this you have decided for, Trevize. How can you doubtthat you have chosen well?"Trevize's head was bent in thought. Finally, he looked up and said,"I may have chosen well, but I must be convinced of that. Thedecision I have made it the most important in the history of humanityand it is not enough that it be a good one. I must know it to be a good one.""What more do you need than what I have told you?""I don't know, but I will find it on Earth." He spoke with absoluteconviction.
Pelorat said, "Golan, the star shows a disc."It did. The computer, busy about its own affairs and not the leastconcerned with any discussion that might swirl about it, had beenapproaching the star in stages, and had reached the distance Trevizehad set for it.
They continued to be well outside the planetary plane and the computersplit the screen to show each of three small inner planets.
It was the innermost that had a surface temperature in the liquid-waterrange, and that had an oxygen atmosphere as well. Trevize waited for itsorbit to be computed and the first crude estimate seemed reasonable. Hekept that computation going, for the longer the planetary movement wasobserved, the more accurate the computation of its orbital elements.
Trevize said quite calmly, "We have a habitable planet in view. Verylikely habitable.""Ah." Pelorat looked as nearly delighted as his solemn expressionwould allow.
"I'm afraid, though," said Trevize, "that there's no giantsatellite. In fact, no satellite of any kind has been detected so far. Soit isn't Earth. At least, not if we go by tradition.""Don't worry about that, Golan." said Pelorat. "I rather suspectedwe weren't going to encounter Earth here when I saw that neither of thegas giants had an unusual ring system.""Very well, then," said Trevize. "The next step is to find out thenature of the life inhabiting it. From the fact that it has an oxygenatmosphere, we can be absolutely certain that there is plant life uponit, but ""Animal life, too," said Bliss abruptly. "And in quantity.""What?" Trevize turned to her.
"I can sense it. Only faintly at this distance, but the planet isunquestionably not only habitable, but inhabited."33The Far Star was in polar orbit about the Forbidden World,at a distance great enough to keep the orbital period at a little inexcess of six days. Trevize seemed in no hurry to come out of orbit.
"Since the planet is inhabited," he explained, "and since, according toDeniador, it was once inhabited by human beings who were technologicallyadvanced and who represent a first wave of Settlers the so-calledSpacers they may be technologically advanced still and may haveno great love for us of the second wave who have replaced them. I wouldlike them to show themselves, so that we can learn a little about thembefore risking a landing.""They may not know we are here," said Pelorat.
"We would, if the situation were reversed. I must assume, then, that,if they exist, they are likely to try to make contact withus. They might even want to come out and get us.""But if they did come out after us and were technologically advanced,we might be helpless to ""I can't believe that," said Trevize. "Technological advancement isnot necessarily all one piece. They might conceivably be far beyond us insome ways, but it's clear they don't indulge in interstellar travel. Itis we, not they, who have settled the Galaxy, and in all the history ofthe Empire, I know of nothing that would indicate that they left theirworlds and made themselves evident to us. If they haven't been spacetraveling, how could they be expected to have made serious advances inastronautics? And if they haven't, they can't possibly have anythinglike a gravitic ship. We may be essentially unarmed but even if theycome lumbering after us with a battleship, they couldn't possibly catchus. No, we wouldn't be helpless.""Their advance may be in mentalics. It may be that the Mule was aSpacer "Trevize shrugged in clear irritation. "The Mule can't beeverything. The Gaians have described him as an aberrant Gaian. He'salso been considered a random mutant."Pelorat said, "To be sure, there have also been speculations nottaken very seriously, of course that he was a mechanical artifact. Arobot, in other words, though that word wasn't used.""If there is something that seems mentally dangerous, we will haveto depend on Bliss to neutralize that. She can Is she asleep now,by the way?""She has been," said Pelorat, "but she was stirring when I cameout here.""Stirring, was she? Well, she'll have to be awake on short notice ifanything starts happening. You'll have to see to that, Janov.""Yes, Golan," said Pelorat quietly.
Trevize shifted his attention to the computer. "One thing that bothersme are the entry stations. Ordinarily, they are a sure sign of a planetinhabited by human beings with a high technology. But these ""Is there something wrong with them?""Several things. In the first place, they're very archaic. Theymight be thousands of years old. In the second, there's no radiationbut thermals.""What are thermals?""Thermal radiation is given off by any object warmer than itssurroundings. It's a familiar signature that everything yields and itconsists of a broad band of radiation following a fixed pattern dependingon temperature. That is what the entry stations are radiating. If thereare working human devices aboard the stations, there is bound to bea leakage of nonthermal, nonrandom radiation. Since only thermals arepresent we can assume that either the stations are empty, and have been,perhaps, for thousands of years; or, if occupied, it is by people with atechnology so advanced in this direction that they leak no radiation.""Perhaps," said Pelorat, "the planet has a high civilization,but the entry stations are empty because the planet has been left sostrictly alone for so long by our kind of Settlers that they are nolonger concerned about any approach.""Perhaps. Or perhaps it is a lure of some sort."Bliss entered, and Trevize, noting her out of the corner of his eyes,said grumpily, "Yes, here we are.""So I see," said Bliss, "and still in an unchanged orbit. I can tellthat much."Pelorat explained hastily. "Golan is being cautious, dear. Theentry stations seem unoccupied and we're not sure of the significanceof that.""There's no need to worry about it," said Bliss indifferently. "Thereare no detectable signs of intelligent life on the planet we'reorbiting."Trevize bent an astonished glare at her. "What are you talkingabout? You said ""I said there was animal life on the planet, and so there is, butwhere in the Galaxy were you taught that animal life necessarily implieshuman life?""Why didn't you say this when you first detected animal life?""Because at that distance, I couldn't tell. I could barely detectthe unmistakable wash of animal neural activity, but there was no wayI could, at that intensity, tell butterflies from human beings.""And now?""We're much closer now, and you may have thought I was asleep, but Iwasn't or, at least, only briefly. I was, to use an inappropriateword, listening as hard as I could for any sign of mental activitycomplex enough to signify the presence of intelligence.""And there isn't any?""I would suppose," said Bliss, with sudden caution, "that if Idetect nothing at this distance, there can't possibly be more than a fewthousand human beings on the planet. If we come closer, I can judge itstill more delicately.""Well, that changes things," said Trevize, with some confusion.
"I suppose," said Bliss, who looked distinctly sleepy and, therefore,irritable. "You can now discard all this business of analyzingradiation and inferring and deducing and who knows what else you mayhave been doing. My Gaian senses do the job much more efficiently andsurely. Perhaps you see what I mean when I say it is better to be aGaian than an Isolate."Trevize waited before answering, clearly laboring to hold histemper. When he spoke, it was with a polite, and almost formal tone, "Iam grateful to you for the information. Nevertheless, you must understandthat, to use an analogy, the thought of the advantage of improving mysense of smell would be insufficient motive for me to decide to abandonmy humanity and become a bloodhound."34They could see the Forbidden World now, as they movedbelow the cloud layer and drifted through the atmosphere. It lookedcuriously moth-eaten.
The polar regions were icy, as might be expected, but they were notlarge in extent. The mountainous regions were barren, with occasionalglaciers, but they were not large in extent, either. There were smalldesert areas, well scattered.
Putting all that aside, the planet was, in potential, beautiful. Itscontinental areas were quite large, but sinuous, so that there werelong shorelines, and rich coastal plains of generous extent. Therewere lush tracts of both tropical and temperate forests, rimmed bygrasslands and yet the moth-eaten nature of it all was evident.
Scattered through the forests were semibarren areas, and parts ofthe grasslands were thin and sparse.
"Some sort of plant disease?" said Pelorat wonderingly.
"No," said Bliss slowly. "Something worse than that, and morepermanent.""I've seen a number of worlds," said Trevize, "but nothing likethis.""I have seen very few worlds," said Bliss, "but I think the thoughtsof Gaia and this is what you might expect of a world from which humanityhas disappeared.""Why?" said Trevize.
"Think about it," said Bliss tartly. "No inhabited world has a trueecological balance. Earth must have had one originally, for if thatwas the world on which humanity evolved, there must have been longages when humanity did not exist, or any species capable of developingan advanced technology and the ability to modify the environment. Inthat case, a natural balance everchanging, of course musthave existed. On all other inhabited worlds, however, human beings havecarefully terraformed their new environments and established plant andanimal life, but the ecological system they introduce is bound to beunbalanced. It would possess only a limited number of species and onlythose that human beings wanted, or couldn't help introducing "Pelorat said, "You know what that reminds me of? Pardon me,Bliss, for interrupting, but it so fits that I can't resist tellingyou right now before I forget. There's an old creation myth I once cameacross; a myth in which life was formed on a planet and consisted of onlya limited assortment of species, just those useful to or pleasant forhumanity. The first human beings then did something silly nevermind what, old fellow, because those old myths are usually symbolic andonly confusing if they are taken literally and the planet's soilwas cursed. `Thorns also and thistles shall it bring forth to thee,'
is the way the curse was quoted though the passage sounds much betterin the archaic Galactic in which it was written. The point is, though,was it really a curse? Things human beings don't like and don't want,such as thorns and thistles, may be needed to balance the ecology."Bliss smiled. "It's really amazing, Pel, how everything reminds youof a legend, and how illuminating they are sometimes. Human beings, interraforming a world, leave out the thorns and thistles, whatever theymay be, and human beings then have to labor to keep the world going. Itisn't a self-supporting organism as Gaia is. It is rather a miscellaneouscollection of Isolates and the collection isn't miscellaneous enoughto allow the ecological balance to persist indefinitely. If humanitydisappears, and if its guiding hands are removed, the world's pattern oflife inevitably begins to fall apart. The planet unterraforms itself."Trevize said skeptically, "If that's what's happening, it doesn'thappen quickly. This world may have been free of human beings for twentythousand years and yet most of it still seems to be very much a goingconcern.""Surely," said Bliss, "that depends on how well the ecological balancewas set up in the first place. If it is a fairly good balance to beginwith, it might last for a long time without human beings. After all,twenty thousand years, though very long in terms of human affairs,is just overnight when compared to a planetary lifetime.""I suppose," said Pelorat, staring intently at the planetary vista,"that if the planet is degenerating, we can be sure that the human beingsare gone."Bliss said, "I still detect no mental activity at the human level andI am willing to suppose that the planet is safely free of humanity. Thereis the steady hum and buzz of lower levels of consciousness, however,levels high enough to represent birds and mammals. Just the same, I'mnot sure that unterraforming is enough to show human beings are gone. Aplanet might deteriorate even if human beings existed upon it, if thesociety were itself abnormal and did not understand the importance ofpreserving the environment.""Surely," said Pelorat, "such a society would quickly be destroyed. Idon't think it would be possible for human beings to fail to understandthe importance of retaining the very factors that are keeping themalive."Bliss said, "I don't have your pleasant faith in human reason,Pel. It seems to me to be quite conceivable that when a planetarysociety consists only of Isolates, local and even individual concernsmight easily be allowed to overcome planetary concerns.""I don't think that's conceivable," said Trevize, "anymore thanPelorat does. In fact, since human-occupied worlds exist by the millionand none of them have deteriorated in an unterraforming fashion, yourfear of Isolatism may be exaggerated, Bliss."The ship now moved out of the daylit hemisphere into the night. Theeffect was that of a rapidly deepening twilight, and then utter darknessoutside, except for starlight where the sky was clear.
The ship maintained its height by accurately monitoring the atmosphericpressure and gravitational intensity. They were at a height too greatto encounter any upthrusting mountainous massif, for the planet wasat a stage when mountain-building had not recently taken place. Still,the computer felt its way forward with its microwave finger-tips, justin case.
Trevize regarded the velvety darkness and said, thoughtfully,"Somehow what I find most convincing as the sign of a deserted planet isthe absence of visible light on the dark side. No technological societycould possibly endure darkness. As soon as we get into the dayside,we'll go lower.""What would be the use of that?" said Pelorat. "There's nothingthere.""Who said there's nothing there?""Bliss did. And you did.""No, Janov. I said there's no radiation of technological origin andBliss said there's no sign of human mental activity, but that doesn'tmean there's nothing there. Even if there are no human beings on theplanet, there would surely be relics of some sort. I'm after information,Janov, and the remainders of a technology may have its uses in thatdirection.""After twenty thousand years?" Pelorat's voice climbed in pitch. "Whatdo you think can survive twenty thousand years? There will be no films,no paper, no print; metal will have rusted, wood will have decayed,plastic will be in shattered grains. Even stone will have crumbledand eroded.""It may not be twenty thousand years," said Trevize patiently. "Imentioned that time as the longest period the planet may have beenleft empty of human beings because Comporellian legend has this worldflourishing at that time. But suppose the last human beings had died orvanished or fled only a thousand years ago."They arrived at the other end of the nightside and the dawn came andbrightened into sunlight almost instantaneously.
The Far Star sank downward and slowed its progress until thedetails of the land surface were clearly visible. The small islands thatdotted the continental shores could now be clearly seen. Most were greenwith vegetation.
Trevize said, "It's my idea that we ought to study the spoiledareas particularly. It seems to me that those places where human beingswere most concentrated would be where the ecological balance was mostlacking. Those areas might be the nucleus of the spreading blight ofunterraforming. What do you think, Bliss?""It's possible. In any case, in the absence of definite knowledge,we might as well look where it's easiest to see. The grasslands andforest would have swallowed most signs of human habitation so thatlooking there might prove a waste of time.""It strikes me," said Pelorat, "that a world might eventuallyestablish a balance with what it has; that new species might develop;and that the bad areas might be recolonized on a new basis.""Possibly, Pel," said Bliss. "It depends on how badly out of balancethe world was in the first place. And for a world to heal itself andachieve a new balance through evolution would take far more than twentythousand years. We'd be talking millions of years."The Far Star was no longer circling the world. It was driftingslowly across a five-hundred-kilometer-wide stretch of scattered heathand furze, with occasional clumps of trees.
"What do you think of that?" said Trevize suddenly, pointing. Theship came to a drifting halt and hovered in mid-air. There was a low, butpersistent, hum as the gravitic engines shifted into high, neutralizingthe planetary gravitational field almost entirely.
There was nothing much to see where Trevize pointed. Tumbled moundsbearing soil and sparse grass were all that was visible.
"It doesn't look like anything to me," said Pelorat.
"There's a straight-line arrangement to that junk. Parallel lines,and you can make out some faint lines at right angles, too. See? Youcan't get that in any natural formation. That's human architecture,marking out foundations and walls, just as clearly as though they werestill standing there to be looked at.""Suppose it is," said Pelorat. "That's just a ruin. If we'regoing to do archeological research, we're going to have to dig anddig. Professionals would take years to do it properly ""Yes, but we can't take the time to do it properly. That may bethe faint outline of an ancient city and something of it may still bestanding. Let's follow those lines and see where they take us."It was toward one end of the area, at a place where the trees weresomewhat more thickly clumped, that they came to standing walls orpartially standing ones.
Trevize said, "Good enough for a beginning. We're landing.
"If I ask questions?""Go ahead."Pelorat said, "What are you doing?"Trevize took his eyes off the viewscreen. "I've got to measure thedistance of each star that seems to be near the Forbidden World onthe screen, so that I can determine how near they really are. Theirgravitational fields must be known and for that I need mass anddistance. Without that knowledge, one can't be sure of a clean Jump.""How do you do that?""Well, each star I see has its co-ordinates in the computer's memorybanks and these can be converted into co-ordinates on the Comporelliansystem. That can, in turn, be slightly corrected for the actual positionof the For Star in space relative to Comporellon's sun, and that givesme the distance of each. Those red dwarfs all look quite near theForbidden World on the screen, but some might be much closer and somemuch farther. We need their three-dimensional position, you see."Pelorat nodded, and said, "And you already have the co-ordinates ofthe Forbidden World ""Yes, but that's not enough. I need the distances of the otherstars to within a percent or so. Their gravitational intensity in theneighborhood of the Forbidden World is so small that a slight errormakes no perceptible difference. The sun about which the Forbidden Worldrevolves or might revolve possessss an enormously intensegravitational field in the neighborhood of the Forbidden World and Imust know its distance with perhaps a thousand times the accuracy ofthat of the other stars. The co-ordinatss alone won't do.""Then what do you do?""I measure the apparent separation of the Forbidden World or,rather, its star from three nearby stars which are so dim it takesconsiderable magnification to make them out at all. Presumably, thosethree are very far away. We then keep one of those three stars centered onthe screen and Jump a tenth of a parsec in a direction at right angles tothe line of vision to the Forbidden World. We can do that safely enougheven without knowing distances to comparatively far-off stars.
"The reference star which is centered would still be centered afterthe Jump. The two other dim stars, if all three are truly very distant,do not change their positions measurably. The Forbidden World, however,is close enough to change its apparent position in parallactic shift. Fromthe size of the shift, we can determine its distance. If I want to makedoubly certain, I choose three other stars and try again."Pelorat said, "How long doss all that take?""Not very long. The computer doss the heavy work. I just tell it whatto do. What really takes the time is that I have to study the resultsand make sure they look right and that my instructions aren't at faultsomehow. If I were one of those daredevils with utter faith in themselvesand the computer, it could all be done in a few minutes."Pelorat said, "It's really astonishing. Think how much the computerdoes for us.""I think of it all the time.""What would you do without it?""What would I do without a gravitic ship? What would I do withoutmy astronautic training? What would I do without twenty thousandyears of hyperspatial technology behind me? The fact is that I'mmyself here now. Suppose weeeere to imagine ourselves twentythousand additional years into the future. What technological marvelswould we have to be grateful for? Or might it be that twenty thousandyears hence humanity would not exist?""Scarcely that," said Pelorat. "Scarcely not exist. Even if wedon't become part of Galaxia, we would still have psychohistory toguide us."Trevize turned in his chair, releasing his handhold on thecomputer. "Let it work out distances," he said, "and let it check thematter a number of times. There's no hurry."He looked quizzically at Pelorat, and said, "Psychohistory! You know,Janov, twice that subject came up on Comporellon, and twice it wasdescribed as a superstition. I said so once, and then Deniador said italso. After all, how can you define psychohistory but as a superstitionof the Foundation? Isn't it a belief without proof or evidence? What doyou think, Janov? It's more your field than mine."Pelorat said, "Why do you say there's no evidence, Golan? Thesimulacrum of Hari Seldon has appeared in the Time Vault many times andhas discussed events as they happened. He could not have known whatthose events would be, in his time, had he not been able to predictthem psychohistorically."Trevize nodded. "That sounds impressive. He was wrong about theMule, but even allowing for that, it's impressive. Still, it has anuncomfortable magical feel to it. Any conjurer can do tricks.""No conjurer could predict centuries into the future.""No conjurer could really do what he makes you think he does.""Come, Golan. I can't think of any trick that would allow me topredict what will happen five centuries from now.""Nor can you think of a trick that will allow a conjurer to readthe contents of a message hidden in a pseudo-tesseract on an unmannedorbiting satellite. Just the same, I've seen a conjurer do it. Has itever occurred to you that the Time Capsule, along with the Hari Seldonsimulacrum, may be rigged by the government?"Pelorat looked as though he were revolted by the suggestion. "Theywouldn't do that."Trevize made a scornful sound.
Pelorat said, "And they'd be caught if they tried.""I'm not at all sure of that. The point is, though, that we don'tknow how psychohistory works at all.""I don't know how that computer works, but I know it works.""That's because others know how it works. How would it be if noone knew how it worked? Then, if it stopped working for any reason, wewould be helpless to do anything about it. And if psychohistory suddenlystopped working ""The Second Foundationers know the workings of psychohistory.""How do you know that, Janov?""So it is said.""Anything can be said. Ah, we have the distance of theForbidden World's star, and, I hope, very accurately. Let's considerthe figures."He stared at them for a long time, his lips moving occasionally,as though he were doing some rough calculations in his head. Finally,he said, without lifting his eyes, "What's Bliss doing?""Sleeping, old chap," said Pelorat. Then, defensively, "Sheneeds sleep, Golan. Maintaining herself as part of Gaiaacross hyperspace is energy-consuming.""I suppose so," said Trevize, and turned back to the computer. Heplaced his hands on the desk and muttered, "I'll let it go in severalJumps and have it recheck each time." Then he withdrew them againand said, "I'm serious, Janov. What do you know aboutpsychohistory?"Pelorat looked taken aback. "Nothing. Being a historian,which I am, after a fashion, is worlds different from being apsychohistorian. Of course, I know the two fundamental basics ofpsychohistory, but everyone knows that.""Even I do. The first requirement is that the number of human beingsinvolved must be large enough to make statistical treatment valid. Buthow large is `large enough'?"Pelorat said, "The latest estimate of the Galactic populationis something like ten quadrillion, and that's probably anunderestimate. Surely, that's large enough.""How do you know?""Because psychohistory does work, Golan. No matter howyou chop logic, it does work.""And the second requirement," said Trevize, "is that human beingsnot be aware of psychohistory, so that the knowledge does not skew theirreactions. But they are aware of psychohistory.""Only of its bare existence, old chap. That's not whatcounts. The second requirement is that human beings not be awareof the predictions of psychohistory and that they arenot except that the Second Foundationers are supposed to be awareof them, but they're a special case.""And upon those two requirements alone , the science ofpsychohistory has been developed. That's hard to believe.""Not out of those two requirements alone, " said Pelorat. "Thereare advanced mathematics and elaborate statistical methods. Thestory is if you want tradition that Hari Seldon devisedpsychohistory by modeling it upon the kinetic theory of gases. Each atomor molecule in a gas moves randomly so that we can't know the position orvelocity of any one of them. Nevertheless, using statistics, we can workout the rules governing their overall behavior with great precision. Inthe same way, Seldon intended to work out the overall behavior of humansocieties even though the solutions would not apply to the behavior ofindividual human beings.""Perhaps, but human beings aren't atoms.""True," said Pelorat. "A human being has consciousness and his behavioris sufficiently complicated to make it appear to be free will. How Seldonhandled that I haven't any idea, and I'm sure I couldn't understandit even if someone who knew tried to explain it to me but hedid it."Trevize said, "And the whole thing depends on dealing with people whoare both numerous and unaware. Doesn't that seem to you a quicksandishfoundation on which to build an enormous mathematical structure? Ifthose requirements are not truly met, then everything collapses.""But since the Plan hasn't collapsed ""Or, if the requirements are not exactly false or inadequate butsimply weaker than they should be, psychohistory might work adequatelyfor centuries and then, upon reaching some particular crisis, wouldcollapse as it did temporarily in the time of the Mule. Orwhat if there is a third requirement?""What third requirement?" asked Pelorat, frowning slightly.
"I don't know," said Trevize. "An argument may seem thoroughlylogical and elegant and yet contain unexpressed assumptions. Maybe thethird requirement is an assumption so taken for granted that no one everthinks of mentioning it.""An assumption that is so taken for granted is usually valid enough,or it wouldn't be so taken for granted."Trevize snorted. "If you knew scientific history as well as you knowtraditional history, Janov, you would know how wrong that is. ButI see that we are now in the neighborhood of the sun of the ForbiddenWorld."And, indeed, centered on the screen, was a bright star one sobright that the screen automatically filtered its light to the pointwhere all other stars were washed out.
32Facilities for washing and for personal hygiene on boardthe Far Star were compact, and the use of water was always held to areasonable minimum to avoid overloading the recycling facilities. BothPelorat and Bliss had been sternly reminded of this by Trevize.
Even so, Bliss maintained an air of freshness at all times and herdark, long hair could be counted on to be glossy, her fingernails tosparkle.
She walked into the pilot-room and said, "There you are!"Trevize looked up and said, "No need for surprise. We could scarcelyhave left the ship, and a thirty-second search would be bound touncover us inside the ship, even if you couldn't detect our presencementally."Bliss said, "The expression was purely a form of greeting and notmeant to be taken literally, as you well know. Where are we? Anddon't say, `In the pilot-room.'""Bliss dear," said Pelorat, holding out one arm, "we're at the outerregions of the planetary system of the nearest of the three ForbiddenWorlds."She walked to his side, placing her hand lightly on his shoulder,while his arm moved about her waist. She said, "It can't be veryForbidden. Nothing has stopped us."Trevize said, "It is only Forbidden because Comporellon and the otherworlds of the second wave of settlement have voluntarily placed the worldsof the first wave the Spacers out of bounds. If we ourselvesdon't feel bound by that voluntary agreement, what is to stop us?""The Spacers, if any are left, might have voluntarily placed theworlds of the second wave out of bounds, too. Just because we don't mindintruding upon them doesn't mean that they don't mind it.""True," said Trevize, "If they exist. But so far we don't even knowif any planet exists for them to live on. So far, all we see are theusual gas giants. Two of them, and not particularly large ones."Pelorat said hastily, "But that doesn't mean the Spacer worlddoesn't exist. Any habitable world would be much closer to the sunand much smaller and very hard to detect in the solar glare from thisdistance. We'll have to micro-Jump inward to detect such a planet." Heseemed rather proud to be speaking like a seasoned space traveler.
"In that case," said Bliss, "why aren't we moving inward?""Not just yet," said Trevize. "I'm having the computer check as faras it can for any sign of an artificial structure. We'll move inwardby stages a dozen, if necessary checking at each stage. Idon't want to be trapped this time as we were when we first approachedGaia. Remember, Janov?""Traps like that could catch us every day. The one at Gaia broughtme Bliss." Pelorat gazed at her fondly.
Trevize grinned. "Are you hoping for a new Bliss every day?"Pelorat looked hurt, and Bliss said, with a trace of annoyance,"My good chap or whatever it is that Pel insists on callingyou you might as well move in more quickly. While I am with you,you will not be trapped.""The power of Gaia?""To detect the presence of other minds? Certainly.""Are you sure you are strong enough, Bliss? I gather you must sleepquite a bit to regain strength expended at maintaining contact with themain body of Gaia. How far can I rely on the perhaps narrow limits ofyour abilities at this distance from the source?"Bliss flushed. "The strength of the connection is ample."Trevize said, "Don't be offended. I'm simply asking. Don't yousee this as a disadvantage of being Gaia? I am not Gaia. I am a completeand independent individual. That means I can travel as far as I wish frommy world and my people, and remain Golan Trevize. What powers I have,and such as they are, I continue to have, and they remain whereverI go. If I were alone in space, parsecs away from any human being,and unable, for some reason, to communicate with anyone in any way,or even to see the spark of a single star in the sky, I would be andremain Golan Trevize. I might not be able to survive, and I might die,but I would die Golan Trevize."Bliss said, "Alone in space and far from all others, you would beunable to call on the help of your fellows, on their different talentsand knowledge. Alone, as an isolated individual, you would be sadlydiminished as compared with youself as part of an integrated society. Youknow that."Trevize said, "There would nevertheless not be the same diminution asin your case. There is a bond between you and Gaia that is far strongerthan the one between me and my society, and that bond stretches throughhyperspace and requires energy for maintenance, so that you must gasp,mentally, with the effort, and feel yourself to be a diminished entityfar more than I must."Bliss's young face set hard and, for a moment, she looked young nomore or, rather, she appeared ageless more Gaia than Bliss, asthough to refute Trevize's contention. She said, "Even if everything yousay is so, Golan Trevize that is, was, and will be, that cannotperhaps be less, but certainly cannot be more even if everythingyou say is so, do you expect there is no price to be paid for a benefitgained? Is it not better to be a warm-blooded creature such as yourselfthan a cold-blooded creature such as a fish, or whatever?"Pelorat said, "Tortoises are cold-blooded. Terminus doesn't have any,but some worlds do. They are shelled creatures, very slow-moving butlong-living.""Well, then, isn't it better to be a human being than a tortoise; tomove quickly whatever the temperature, rather than slowly? Isn't it betterto support high-energy activities, quickly contracting muscles, quicklyworking nerve fibers, intense and long-sustained thought than tocreep slowly, and sense gradually, and have only a blurred awareness ofthe immediate surroundings? Isn't it?""Granted," said Trevize. "It is. What of it?""Well, don't you know you must pay for warm-bloodedness? To maintainyour temperature above that of your surroundings, you must expend energyfar more wastefully than a tortoise must. You must be eating almostconstantly so that you can pour energy into your body as quickly as itleaks out. You would starve far more quickly than a tortoise would,and die more quickly, too. Would you rather be a tortoise, and livemore slowly and longer? Or would you rather pay the price and be aquick-moving, quick-sensing, thinking organism?""Is this a true analogy, Bliss?""No, Trevize, for the situation with Gaia is more favorable. We don'texpend unusual quantities of energy when we are compactly together. It isonly when part of Gaia is at hyperspatial distances from the rest of Gaiathat energy expenditure rises. And remember that what you have votedfor is not merely a larger Gaia, not just a larger individual world. Youhave decided for Galaxia, for a vast complex of worlds. Anywhere in theGalaxy, you will be part of Galaxia and you will be closely surroundedby parts of something that extends from each interstellar atom to thecentral black hole. It would then require small amounts of energy toremain a whole. No part would be at any great distance from all otherparts. It is all this you have decided for, Trevize. How can you doubtthat you have chosen well?"Trevize's head was bent in thought. Finally, he looked up and said,"I may have chosen well, but I must be convinced of that. Thedecision I have made it the most important in the history of humanityand it is not enough that it be a good one. I must know it to be a good one.""What more do you need than what I have told you?""I don't know, but I will find it on Earth." He spoke with absoluteconviction.
Pelorat said, "Golan, the star shows a disc."It did. The computer, busy about its own affairs and not the leastconcerned with any discussion that might swirl about it, had beenapproaching the star in stages, and had reached the distance Trevizehad set for it.
They continued to be well outside the planetary plane and the computersplit the screen to show each of three small inner planets.
It was the innermost that had a surface temperature in the liquid-waterrange, and that had an oxygen atmosphere as well. Trevize waited for itsorbit to be computed and the first crude estimate seemed reasonable. Hekept that computation going, for the longer the planetary movement wasobserved, the more accurate the computation of its orbital elements.
Trevize said quite calmly, "We have a habitable planet in view. Verylikely habitable.""Ah." Pelorat looked as nearly delighted as his solemn expressionwould allow.
"I'm afraid, though," said Trevize, "that there's no giantsatellite. In fact, no satellite of any kind has been detected so far. Soit isn't Earth. At least, not if we go by tradition.""Don't worry about that, Golan." said Pelorat. "I rather suspectedwe weren't going to encounter Earth here when I saw that neither of thegas giants had an unusual ring system.""Very well, then," said Trevize. "The next step is to find out thenature of the life inhabiting it. From the fact that it has an oxygenatmosphere, we can be absolutely certain that there is plant life uponit, but ""Animal life, too," said Bliss abruptly. "And in quantity.""What?" Trevize turned to her.
"I can sense it. Only faintly at this distance, but the planet isunquestionably not only habitable, but inhabited."33The Far Star was in polar orbit about the Forbidden World,at a distance great enough to keep the orbital period at a little inexcess of six days. Trevize seemed in no hurry to come out of orbit.
"Since the planet is inhabited," he explained, "and since, according toDeniador, it was once inhabited by human beings who were technologicallyadvanced and who represent a first wave of Settlers the so-calledSpacers they may be technologically advanced still and may haveno great love for us of the second wave who have replaced them. I wouldlike them to show themselves, so that we can learn a little about thembefore risking a landing.""They may not know we are here," said Pelorat.
"We would, if the situation were reversed. I must assume, then, that,if they exist, they are likely to try to make contact withus. They might even want to come out and get us.""But if they did come out after us and were technologically advanced,we might be helpless to ""I can't believe that," said Trevize. "Technological advancement isnot necessarily all one piece. They might conceivably be far beyond us insome ways, but it's clear they don't indulge in interstellar travel. Itis we, not they, who have settled the Galaxy, and in all the history ofthe Empire, I know of nothing that would indicate that they left theirworlds and made themselves evident to us. If they haven't been spacetraveling, how could they be expected to have made serious advances inastronautics? And if they haven't, they can't possibly have anythinglike a gravitic ship. We may be essentially unarmed but even if theycome lumbering after us with a battleship, they couldn't possibly catchus. No, we wouldn't be helpless.""Their advance may be in mentalics. It may be that the Mule was aSpacer "Trevize shrugged in clear irritation. "The Mule can't beeverything. The Gaians have described him as an aberrant Gaian. He'salso been considered a random mutant."Pelorat said, "To be sure, there have also been speculations nottaken very seriously, of course that he was a mechanical artifact. Arobot, in other words, though that word wasn't used.""If there is something that seems mentally dangerous, we will haveto depend on Bliss to neutralize that. She can Is she asleep now,by the way?""She has been," said Pelorat, "but she was stirring when I cameout here.""Stirring, was she? Well, she'll have to be awake on short notice ifanything starts happening. You'll have to see to that, Janov.""Yes, Golan," said Pelorat quietly.
Trevize shifted his attention to the computer. "One thing that bothersme are the entry stations. Ordinarily, they are a sure sign of a planetinhabited by human beings with a high technology. But these ""Is there something wrong with them?""Several things. In the first place, they're very archaic. Theymight be thousands of years old. In the second, there's no radiationbut thermals.""What are thermals?""Thermal radiation is given off by any object warmer than itssurroundings. It's a familiar signature that everything yields and itconsists of a broad band of radiation following a fixed pattern dependingon temperature. That is what the entry stations are radiating. If thereare working human devices aboard the stations, there is bound to bea leakage of nonthermal, nonrandom radiation. Since only thermals arepresent we can assume that either the stations are empty, and have been,perhaps, for thousands of years; or, if occupied, it is by people with atechnology so advanced in this direction that they leak no radiation.""Perhaps," said Pelorat, "the planet has a high civilization,but the entry stations are empty because the planet has been left sostrictly alone for so long by our kind of Settlers that they are nolonger concerned about any approach.""Perhaps. Or perhaps it is a lure of some sort."Bliss entered, and Trevize, noting her out of the corner of his eyes,said grumpily, "Yes, here we are.""So I see," said Bliss, "and still in an unchanged orbit. I can tellthat much."Pelorat explained hastily. "Golan is being cautious, dear. Theentry stations seem unoccupied and we're not sure of the significanceof that.""There's no need to worry about it," said Bliss indifferently. "Thereare no detectable signs of intelligent life on the planet we'reorbiting."Trevize bent an astonished glare at her. "What are you talkingabout? You said ""I said there was animal life on the planet, and so there is, butwhere in the Galaxy were you taught that animal life necessarily implieshuman life?""Why didn't you say this when you first detected animal life?""Because at that distance, I couldn't tell. I could barely detectthe unmistakable wash of animal neural activity, but there was no wayI could, at that intensity, tell butterflies from human beings.""And now?""We're much closer now, and you may have thought I was asleep, but Iwasn't or, at least, only briefly. I was, to use an inappropriateword, listening as hard as I could for any sign of mental activitycomplex enough to signify the presence of intelligence.""And there isn't any?""I would suppose," said Bliss, with sudden caution, "that if Idetect nothing at this distance, there can't possibly be more than a fewthousand human beings on the planet. If we come closer, I can judge itstill more delicately.""Well, that changes things," said Trevize, with some confusion.
"I suppose," said Bliss, who looked distinctly sleepy and, therefore,irritable. "You can now discard all this business of analyzingradiation and inferring and deducing and who knows what else you mayhave been doing. My Gaian senses do the job much more efficiently andsurely. Perhaps you see what I mean when I say it is better to be aGaian than an Isolate."Trevize waited before answering, clearly laboring to hold histemper. When he spoke, it was with a polite, and almost formal tone, "Iam grateful to you for the information. Nevertheless, you must understandthat, to use an analogy, the thought of the advantage of improving mysense of smell would be insufficient motive for me to decide to abandonmy humanity and become a bloodhound."34They could see the Forbidden World now, as they movedbelow the cloud layer and drifted through the atmosphere. It lookedcuriously moth-eaten.
The polar regions were icy, as might be expected, but they were notlarge in extent. The mountainous regions were barren, with occasionalglaciers, but they were not large in extent, either. There were smalldesert areas, well scattered.
Putting all that aside, the planet was, in potential, beautiful. Itscontinental areas were quite large, but sinuous, so that there werelong shorelines, and rich coastal plains of generous extent. Therewere lush tracts of both tropical and temperate forests, rimmed bygrasslands and yet the moth-eaten nature of it all was evident.
Scattered through the forests were semibarren areas, and parts ofthe grasslands were thin and sparse.
"Some sort of plant disease?" said Pelorat wonderingly.
"No," said Bliss slowly. "Something worse than that, and morepermanent.""I've seen a number of worlds," said Trevize, "but nothing likethis.""I have seen very few worlds," said Bliss, "but I think the thoughtsof Gaia and this is what you might expect of a world from which humanityhas disappeared.""Why?" said Trevize.
"Think about it," said Bliss tartly. "No inhabited world has a trueecological balance. Earth must have had one originally, for if thatwas the world on which humanity evolved, there must have been longages when humanity did not exist, or any species capable of developingan advanced technology and the ability to modify the environment. Inthat case, a natural balance everchanging, of course musthave existed. On all other inhabited worlds, however, human beings havecarefully terraformed their new environments and established plant andanimal life, but the ecological system they introduce is bound to beunbalanced. It would possess only a limited number of species and onlythose that human beings wanted, or couldn't help introducing "Pelorat said, "You know what that reminds me of? Pardon me,Bliss, for interrupting, but it so fits that I can't resist tellingyou right now before I forget. There's an old creation myth I once cameacross; a myth in which life was formed on a planet and consisted of onlya limited assortment of species, just those useful to or pleasant forhumanity. The first human beings then did something silly nevermind what, old fellow, because those old myths are usually symbolic andonly confusing if they are taken literally and the planet's soilwas cursed. `Thorns also and thistles shall it bring forth to thee,'
is the way the curse was quoted though the passage sounds much betterin the archaic Galactic in which it was written. The point is, though,was it really a curse? Things human beings don't like and don't want,such as thorns and thistles, may be needed to balance the ecology."Bliss smiled. "It's really amazing, Pel, how everything reminds youof a legend, and how illuminating they are sometimes. Human beings, interraforming a world, leave out the thorns and thistles, whatever theymay be, and human beings then have to labor to keep the world going. Itisn't a self-supporting organism as Gaia is. It is rather a miscellaneouscollection of Isolates and the collection isn't miscellaneous enoughto allow the ecological balance to persist indefinitely. If humanitydisappears, and if its guiding hands are removed, the world's pattern oflife inevitably begins to fall apart. The planet unterraforms itself."Trevize said skeptically, "If that's what's happening, it doesn'thappen quickly. This world may have been free of human beings for twentythousand years and yet most of it still seems to be very much a goingconcern.""Surely," said Bliss, "that depends on how well the ecological balancewas set up in the first place. If it is a fairly good balance to beginwith, it might last for a long time without human beings. After all,twenty thousand years, though very long in terms of human affairs,is just overnight when compared to a planetary lifetime.""I suppose," said Pelorat, staring intently at the planetary vista,"that if the planet is degenerating, we can be sure that the human beingsare gone."Bliss said, "I still detect no mental activity at the human level andI am willing to suppose that the planet is safely free of humanity. Thereis the steady hum and buzz of lower levels of consciousness, however,levels high enough to represent birds and mammals. Just the same, I'mnot sure that unterraforming is enough to show human beings are gone. Aplanet might deteriorate even if human beings existed upon it, if thesociety were itself abnormal and did not understand the importance ofpreserving the environment.""Surely," said Pelorat, "such a society would quickly be destroyed. Idon't think it would be possible for human beings to fail to understandthe importance of retaining the very factors that are keeping themalive."Bliss said, "I don't have your pleasant faith in human reason,Pel. It seems to me to be quite conceivable that when a planetarysociety consists only of Isolates, local and even individual concernsmight easily be allowed to overcome planetary concerns.""I don't think that's conceivable," said Trevize, "anymore thanPelorat does. In fact, since human-occupied worlds exist by the millionand none of them have deteriorated in an unterraforming fashion, yourfear of Isolatism may be exaggerated, Bliss."The ship now moved out of the daylit hemisphere into the night. Theeffect was that of a rapidly deepening twilight, and then utter darknessoutside, except for starlight where the sky was clear.
The ship maintained its height by accurately monitoring the atmosphericpressure and gravitational intensity. They were at a height too greatto encounter any upthrusting mountainous massif, for the planet wasat a stage when mountain-building had not recently taken place. Still,the computer felt its way forward with its microwave finger-tips, justin case.
Trevize regarded the velvety darkness and said, thoughtfully,"Somehow what I find most convincing as the sign of a deserted planet isthe absence of visible light on the dark side. No technological societycould possibly endure darkness. As soon as we get into the dayside,we'll go lower.""What would be the use of that?" said Pelorat. "There's nothingthere.""Who said there's nothing there?""Bliss did. And you did.""No, Janov. I said there's no radiation of technological origin andBliss said there's no sign of human mental activity, but that doesn'tmean there's nothing there. Even if there are no human beings on theplanet, there would surely be relics of some sort. I'm after information,Janov, and the remainders of a technology may have its uses in thatdirection.""After twenty thousand years?" Pelorat's voice climbed in pitch. "Whatdo you think can survive twenty thousand years? There will be no films,no paper, no print; metal will have rusted, wood will have decayed,plastic will be in shattered grains. Even stone will have crumbledand eroded.""It may not be twenty thousand years," said Trevize patiently. "Imentioned that time as the longest period the planet may have beenleft empty of human beings because Comporellian legend has this worldflourishing at that time. But suppose the last human beings had died orvanished or fled only a thousand years ago."They arrived at the other end of the nightside and the dawn came andbrightened into sunlight almost instantaneously.
The Far Star sank downward and slowed its progress until thedetails of the land surface were clearly visible. The small islands thatdotted the continental shores could now be clearly seen. Most were greenwith vegetation.
Trevize said, "It's my idea that we ought to study the spoiledareas particularly. It seems to me that those places where human beingswere most concentrated would be where the ecological balance was mostlacking. Those areas might be the nucleus of the spreading blight ofunterraforming. What do you think, Bliss?""It's possible. In any case, in the absence of definite knowledge,we might as well look where it's easiest to see. The grasslands andforest would have swallowed most signs of human habitation so thatlooking there might prove a waste of time.""It strikes me," said Pelorat, "that a world might eventuallyestablish a balance with what it has; that new species might develop;and that the bad areas might be recolonized on a new basis.""Possibly, Pel," said Bliss. "It depends on how badly out of balancethe world was in the first place. And for a world to heal itself andachieve a new balance through evolution would take far more than twentythousand years. We'd be talking millions of years."The Far Star was no longer circling the world. It was driftingslowly across a five-hundred-kilometer-wide stretch of scattered heathand furze, with occasional clumps of trees.
"What do you think of that?" said Trevize suddenly, pointing. Theship came to a drifting halt and hovered in mid-air. There was a low, butpersistent, hum as the gravitic engines shifted into high, neutralizingthe planetary gravitational field almost entirely.
There was nothing much to see where Trevize pointed. Tumbled moundsbearing soil and sparse grass were all that was visible.
"It doesn't look like anything to me," said Pelorat.
"There's a straight-line arrangement to that junk. Parallel lines,and you can make out some faint lines at right angles, too. See? Youcan't get that in any natural formation. That's human architecture,marking out foundations and walls, just as clearly as though they werestill standing there to be looked at.""Suppose it is," said Pelorat. "That's just a ruin. If we'regoing to do archeological research, we're going to have to dig anddig. Professionals would take years to do it properly ""Yes, but we can't take the time to do it properly. That may bethe faint outline of an ancient city and something of it may still bestanding. Let's follow those lines and see where they take us."It was toward one end of the area, at a place where the trees weresomewhat more thickly clumped, that they came to standing walls orpartially standing ones.
Trevize said, "Good enough for a beginning. We're landing.