Pastwatch

by Orson Scott Card

  What Colón did not know, what none of them knew, was how deeply his words had touched Talavera’s soul. A Crusade to liberate Constantinople! To break the power of the Turk! To plunge a knife into the heart of Islam! In a few sentences Colón had forced Talavera to view his life’s work in a new light. All these years that Talavera had devoted himself to the cause of Spain for Christ’s sake, and now he realized that next to Colón his own faith was childish. Colón is right: If we serve Christ, why are we chasing mice when the great bull of Satan struts through the greatest Christian city?

  For the first time in years, Talavera realized that serving the King and Queen might not be identical to serving the cause of Christ. He realized that for the first time in his life he was in the presence of someone whose devotion to Christ might well be the match of his own. Such was my pride, thought Talavera, that it took me this many years to see it.

  And in those years, what have I done? I have kept Colón trapped here, leading him on, keeping the question open year after year, all because making any kind of decision might weaken the relationship between Aragon and Castile. Yet what if it is Colón, and not Ferdinand and Isabella, who understands what will best serve the cause of Christ? How does the purification of Spain compare to the liberation of all the ancient Christian lands? And with the power of Islam broken, what then would stop Christianity from spreading forth to fill the world?

  If only Colón had come to us with a plan for Crusade instead of this strange voyage to the west. The man was eloquent, forceful, and there was something about him that made you want to be on his side. Talavera imagined him going from king to king, from court to court. He might well have been able to convince the monarchs of Europe to unite in common cause against the Turk.

  Instead, Colón seemed sure that the only way to bring about such a Crusade was to establish a direct, quick connection with the great kingdoms of the East. Well, what if he was right? What if God had put his vision in his mind? Certainly it was nothing an intelligent man would have thought of on his own—the most rational plan was to sail around Africa as the Portuguese were doing. But wasn’t that, too, a species of madness? Weren’t there ancient writers who had assumed that Africa extended all the way to the south pole, so there was no way to sail around it? Yet the Portuguese had persisted, finding again and again that no matter how far south they sailed, Africa was always there, extending even farther than they had imagined. Yet last year Dias at last returned with the good news—they had rounded a cape and found that the coast ran to the east, not to the south; and then, after hundreds of miles, it definitely ran to the northeast and then the north. They had rounded Africa. And now the irrational persistence of the Portuguese was widely known to be rational after all.

  Couldn’t Colón’s irrational plans turn out the same way? Only instead of a years-long voyage, his route to the Orient would bring wealth much faster. And his plan, instead of enriching a tiny useless country like Portugal, would lead eventually to the Church of Christ filling the entire world!

  So now, instead of thinking how to drag out the examination of Colón, waiting for the desires of the monarchs to resolve themselves, Talavera sat in his austere chamber trying to think how to force the issue. One thing he certainly could not do was suddenly, after all these years and with no significant new arguments, announce that the committee was deciding in favor of Colón. Maldonado and his supporters would protest directly to the King’s men, and a power struggle would ensue. The Queen would almost certainly lose such an open struggle, since her support from the lords of her realm depended in large part on the fact that she was known to “think like a man.” Disagreeing openly with the King would give the lie to that idea. Thus open support for Colón would lead to division and probably would not lead to a voyage.

  No, Talavera thought, the one thing I cannot do is support Colón. So what can I do?

  I can set him free. I can end the process and let him go on to another king, to another court. Talavera well knew that Colón’s friends had made discreet inquiries in the courts of France and England. Now that the Portuguese had achieved their quest for an African route to the East, they might be able to afford a small exploratory expedition toward the west. Certainly the Portuguese advantage in trading with the Orient will be envied by other kings. Colón might well succeed somewhere. So whatever else happens, I must end his examination immediately.

  But could there not also be a way to end the examination and yet turn things to the advantage of Colón’s supporters?

  With a half-formed plan in mind, Talavera sent to the Queen a note bearing his request for a secret audience with her on the matter of Colón.

  Tagiri did not understand her own reaction to the news of success from the scientists working on time travel. She should be happy. She should be rejoicing to know that her great work could, physically, be accomplished. Yet ever since the meeting with the team of physicists, mathematicians, and engineers working on the time travel project, she had been upset, angry, frightened. The opposite of how she had expected she would feel.

  Yes, they said, we can send a living person into the past. But if we do so there is no chance, no chance whatsoever, that our present world will survive in any form. To send someone into the past to change it is the end of ourselves.

  They were so patient, trying to explain temporal physics to historians. “If our time is destroyed,” Hassan asked, “then won’t that also destroy the very people that we send back? If none of us are ever born, then the people we send won’t have been born either, and therefore they could never have been sent.”

  No, explained the physicists, you’re confusing causality with time. Time itself, as a phenomenon, is utterly linear and unidirectional. Each moment happens only once, and passes into the next moment. Our memories grasp this oneway flow of time, and in our minds we link it with causality. We know that if A causes B, then A must come before B. But there is nothing in the physics of time that requires this. Think of what your predecessors did. The machine they sent back in time was the product of a long causal network. Those causes were all real, and the machine actually existed. Sending it back in time did not undo any of the events that led to the creation of that machine. But in the moment that the machine caused Columbus to see his vision on that beach in Portugal, it began to transform the causal network so that it no longer led to the same place. All of those causes and effects really happened—the ones leading to the creation of the machine, and the ones following from the machine’s introduction into the fifteenth century.

  “But then you’re saying that their future still exists,” Hunahpu protested.

  That depends on how you define existence, they explained. As a part of the causal network leading to the present moment, yes, they continue to exist in the sense that any part of their causal network that led to the existence of their machine in our time is still having effects in the present world. But anything peripheral or irrelevant to that is now utterly without effect in our timestream. And anything in their history that the introduction of that machine in our history caused not to happen is utterly and irrevocably lost. We can’t go back into our past and view it because it didn’t happen.

  “But it did happen, because their machine exists.”

  No, they said again. Causality can be recursive, but time cannot. Anything that the introduction of their machine caused not to happen, did not in fact happen in time. There is no moment of time in which those events exist. Therefore they cannot be seen or visited because the temporal loci which they occupied are now occupied by different moments. Two contradictory sets of events cannot occupy the same moment: You are only confused because you cannot separate causality from time. And that’s perfectly natural, because time is rational. Causality is irrational. We’ve been playing speculative games with the mathematics of time for centuries, but we would never have seen this distinction between time and causality ourselves if we hadn’t had to account for the machine from the future.

  “So what you’
re saying,” Diko offered, “is that the other history still exists, but we just can’t see it with our machines.”

  That’s not what we’re saying, they replied with infinite patience. Anything that was not causally connected to the creation of that machine cannot be said to have ever existed at all. And anything that did lead to the creation of that machine and its introduction into our time exists only in the sense that unreal numbers exist.

  “But they did exist,” Tagiri said, more passionately than she had expected. “They did.”

  “They did not,” said old Manjam, who had let his younger colleagues speak for him till now. “We mathematicians are quite comfortable with this—we have never dwelt in the realm of reality. But of course your mind rebels against it because your mind exists in time. What you must understand is that causality is not real. It does not exist in time. Moment A does not really cause Moment B in reality. Moment A exists, and then Moment B exists, and between them are Moments A.a through A.z, and between A.a and A.b there are A.aa through A.az. None of these moments actually touches any other moment. That is what reality is—an infinite array of discrete moments unconnected with any other moment because each moment in time has no linear dimension. When the machine was introduced into our history, from that point forward a new infinite set of moments completely replaced the old infinite set of moments. There were no spare leftover moment-locations for the old moments to hang around in. And because there was no time for them, they didn’t happen. But causality is unaffected by this. It isn’t geometric. It has a completely different mathematics, one which does not fit well with concepts like space and time and certainly doesn’t fit within anything that you could call ‘real.’ There is no space or time in which those events happened.”

  “What does that mean?” said Hassan. “That if we send somebody back in time, they will suddenly cease to remember anything about the time they came from, because that time no longer exists?”

  “The person that you send back,” said Manjam, “is a discrete event. He will have a brain, and that brain will contain memories that, when he accesses them, will give him certain information. This information will cause him to think he remembers a whole reality, a world and a history. But all that exists in reality is him and his brain. The causal network will only include those causal connections which led to the creation of his physical body, including his brain state, but any part of that causal network which is not part of the new reality cannot be said to exist in any way.”

  Tagiri was shaken. “I don’t care that I don’t understand the science of it,” she said. “I only know that I hate it.”

  “It’s always frightening to deal with something that is counterintuitive,” said Manjam.

  “Not at all,” said Tagiri, trembling. “I didn’t say I was frightened. I’m not. I’m angry and . . . frustrated. Horrified.”

  “Horrified about the mathematics of time?”

  “Horrified at what we are doing, at what the Interveners actually did. I suppose that I always felt that in some sense they went on. That they sent their machine and then went on with their lives, comforted in their miserable situation by knowing that they had done something to help their ancestors.”

  “But that was never possible,” said Manjam.

  “I know it,” said Tagiri. “And so when I really thought about it, I imagined them sending the machine and in that moment they sort of—disappeared. A clean painless death for everyone. But at least they had lived, up to that moment.”

  “Well,” said Manjam, “how is clean, painless nonexistence any worse than a clean, painless death?”

  “You see,” said Tagiri, “it’s not. Not any worse. And not any better, either, for the people themselves.”

  “What people?” said Manjam, shrugging.

  “Us, Manjam. We are talking about doing this to ourselves.”

  “If you do this, then there will have been no such people as ourselves. The only aspect of our causal network that will have any future or past are those that are connected to the creation of the physical bodies and mental states of the persons you send into the past.”

  “This is all so silly,” said Diko. “Who cares about what’s real and what isn’t real? Isn’t this what we wanted all along? To make it so that the terrible events of our history never happened in the first place? And as for our own history, the parts that will be lost, who cares if a mathematician calls us dirty names like ‘unreal’? They say such slanders about the square root of minus two, as well.”

  Everyone laughed, but not Tagiri. They did not see the past as she saw it. Or rather, they didn’t feel the past. They didn’t understand that to her, looking through the Tempoview and the TruSite II, the past was alive and real. Just because the people were dead did not mean that they were not still part of the present, because she could go back and recover them. See them, hear them. Know them, at least as well as any human being ever knows any other. Even before the TruSite and the Tempoview, though, the dead still lived in memory, some kind of memory. But not if they changed the past. It was one thing to ask humankind of today to choose to give up their future in the hope of creating a new reality. That would be hard enough. But to also reach back and kill the dead, to uncreate them as well—and they had no vote. They could not be asked.

  We must not do this, she thought. This is wrong. This will be a worse crime than the ones we are trying to prevent.

  She got up and left the meeting. Diko and Hassan tried to leave with her, but she brushed them off. “I need to be alone,” she said, and so they stayed behind, returning to a meeting that she knew would be in shambles. For a moment she felt remorse at having greeted the physicists’ triumphant moment with such a negative response, but as she walked the streets of Juba that remorse faded, replaced by one far deeper.

  The children playing naked in the dirt and weeds. The men and women going about their business. She spoke to them all in her heart, saying, How would you like to die? And not only you, but your children and their children? And not only them, but your parents, too? Let’s go back into the graves, open them up, and kill them all. Every good and evil thing they did, all their joy, all their suffering, all their choices—let’s kill them all, erase them, undo them. Reaching back and back and back, until we finally come to the golden moment that we have chosen, declaring it worthy to continue to exist, but with a new future tied to the end of it. And why must all of you and yours be killed? Because in our judgment they didn’t make a good enough world. Their mistakes along the way were so unforgivable that they erase the value of any good that also happened. All must be obliterated.

  How dare I? How dare we? Even if we got the unanimous consent of all the people of our own time, how will we poll the dead?

  She picked her way down the bluffs to the riverside. In the waning afternoon, the heat of the day was finally beginning to break. In the distance, hippos were bathing or feeding or sleeping. Birds were calling, getting ready for their frenzied feeding on the insects of the dusk. What goes through your minds, Birds, Hippopotamuses, Insects of the late afternoon? Do you like being alive? Do you fear death? You kill to live; you die so others can live; it’s the path ordained for you by evolution, by life itself. But if you had the power, wouldn’t you save yourselves?

  She was still there by the river when the darkness came, when the stars came out. For a moment, gazing at the ancient light of the stars, she thought: Why should I worry about uncreating so much of human history? Why should I care that it will be worse than forgotten, that it will be unknown? Why should that seem to be a crime, when all of human history is an eyeblink compared to the billions of years the stars have shone? We will all be forgotten in the last exhalation of our history; what does it matter, then, if some are forgotten sooner than others, or if some are caused to have never existed at all?

  Oh, this is such a wise perspective, to compare human lives to the lives of stars. The only problem is that it cuts both ways. If in the long run it doesn’t matter that we
wipe out billions of lives in order to save our ancestors, then in the long run saving our ancestors doesn’t matter, either, so why bother changing the past at all?

  The only perspective that matters is the human one, Tagiri knew. We are the only ones who care; we are the actors and the audience as well, all of us. And the critics. We are also the critics.

  The light of an electric torch bobbed into view as she heard someone approaching through the grass.

  “That torch will only attract animals that we don’t want,” she said.

  “Come home,” said Diko. “It isn’t safe out here, and Father’s worried.”

  “Why should he be worried? My life doesn’t exist. I never lived.”

  “You’re alive now, and so am I, and so are the crocodiles.”

  “If individual lives don’t matter,” said Tagiri, “then why bother going back to make them better? And if they do matter, then how dare we snuff some out in favor of others?”

  “Individual lives matter,” said Diko. “But life also matters. Life as a whole. That’s what you’ve forgotten today. That’s what Manjam and the other scientists also forgot. They talk of all these moments, separate, never touching, and say that they are the only reality. Just as the only reality of human life is individuals, isolated individuals who never really know each other, never really touch at any point. No matter how close you are, you’re always separate.”

  Tagiri shook her head. “This has nothing to do with what is bothering me.”

  “It has everything to do with it,” said Diko. “Because you know that this is a lie. You know that the mathematicians are wrong about the moments, too. They do touch. Even if we can’t really touch causality, the connections between moments, that doesn’t mean they aren’t real. And just because whenever you look closely at the human race, at a community, at a family, all you can ever find are separate individuals, that doesn’t mean that the family is not also real. After all, when you look closely enough at a molecule, all you can see are atoms. There is no physical connection between them. And yet the molecule is still real because of the way the atoms affect each other.”