PROBABILITY MOON

by Nancy Kress

  Gruber said, “Just how small is this grid? Are we down to the single-atom level here?”

  “Yes, and that’s one of the problems. With the calcium ion trigger, we’re close to quantum level. Research is difficult because measurement affects the outcome. One theory says that so do mental events.”

  “I don’t understand what you mean,” Bazargan said.

  “All right. Briefly–I am getting to Voratur’s brain scan, really!—what happens seems to be this. You think of something unconnected with any immediate external stimuli. For instance, you’re alone in your room in the dark, and you think of someone you left on Earth. A loved one. Suddenly you can see her in your mind’s eye, even smell her. Your whole body reacts physically. But what started that cascade? A memory with no identifiable energy source in your brain, without even a single location. It’s just a pattern of scattered neural configurations. We call that a ‘mental event.’ But this nonphysical event started a whole chain of electrical firings that triggered—some of the time!—a whole chain of neurotransmitter balloons.

  “How does that happen? Why do presynaptic grids release balloons sometimes but not other times, when the voltage is the same? What’s going on at the atomic level? We just don’t know.”

  The “basics” had gone on long enough for Bazargan. He said, “But Ann … how does this all apply to Voratur’s brain? What is that second big difference you mentioned between his brain and ours?”

  She smiled. “I’m getting carried away, right?”

  “No!” Allen said explosively. “It’s good to see a scientist who doesn’t treat hard data like a comedy routine.” He scowled at Gruber, who didn’t notice.

  “Voratur’s brain,” Bazargan reminded patiently.

  “Yes. All right. All the cerebral structures are identical to ours. Evoked emotions follow the same neural pathways as ours. Gamma oscillation matches ours. So does neural voltage, neurotransmitter composition, and all other process trackings. The only real difference the Lagerfeld scan showed was greater activity in both the ventral anterior cingulate and in the nucleus accubens.”

  Allen said eagerly, “What are they?”

  “The anterior cingulate is a little structure behind the bridge of the nose that—”

  “That’s where shared-reality headpain is!” Allen crowed.

  “Yes. But the anterior cingulate isn’t causing the headaches. I mean, it is, in that it’s causing the release of pain-inducing transmitters. But the anterior cingulate only coordinates information from many different brain areas. For instance, it’s one of the few cerebral structures connected directly to the hypothalamus, which initiates response to stress. But—and let me be clear on this—the anterior cingulate is not the seat of the shared-reality mechanism. It’s only a switchboard for processing it. The cingulate just sets off cascades of stress transmitters when reality is not shared, or pleasure transmitters when it is.”

  “So where is the source of this shared reality?” Gruber said.

  “That’s just it—there isn’t one! In Worlders’ presynaptic grids, different amounts of neurotransmitters are being released than in human brains. But the input to cause the release—the voltage of neural firings—is exactly the same! Same input, same processors, different output. It makes no sense.”

  Bazargan said diffidently, “And of course you’ve ruled out pathogens, environmental toxins, dietary diff—”

  “Yes, of course I have.” It was rare for Ann to be curt. “All those would have showed up on the Lagerfeld.”

  Gruber grinned. “A mystery, yes? Factor X. A spiritual radio wave, an invisible personal download?”

  Allen said coolly, “Don’t be ridiculous.”

  “Don’t be premature,” Bazargan said to Ann. “You’ve gained an astonishing amount of data, Ann. In time you may be able to put it all together.”

  She smiled tiredly. “I want it now. It just doesn’t add up. And look! That’s another thing!”

  “What’s another thing?” Bazargan said.

  “This ‘lifegiver,’” Ann answered, and now he saw the small pseudo-insect on her bare shoulder, just short of her tunic strap. Windows were always open on World. The lifegiver folded its transparent wings and settled onto Ann’s skin, gripping with tiny suckers. Its yellow body was faintly luminescent.

  Ann said, “This is as close as they’ll ever get to anyone’s head. Human, Worlder—they won’t ever perch on anybody’s head. I was hoping the Lagerfeld scan would show some logical reason why, something about the electrical field generated by the brain, maybe, set alongside a lifegiver field. But no, nothing.”

  “Another mystery,” Bazargan said, “at least for now. But let’s focus instead on what we did learn. The Worlder headache when ‘shared reality’ is violated … it’s a real, physiological, documentable phenomenon?”

  “Oh, yes,” Ann said. “Although remember that even in humans, the relationship between emotional physiology and moral judgment is complex. Consider the sociopath. He performs amoral acts, such as casual murder, because he has no feeling whatsoever for his victim. Worlders are just the opposite. They have what we would consider an excess of relationship between their physiology and their moral sense. It’s partly learned behavior, in that children are heavily socialized about how to react to their feelings of repulsion and pain when people say things that violate cultural mores. But the repulsion and pain are real and documentable. Shared reality has a solid physiological basis.”

  “An evolutionary advancement,” David said. “The next step in hominid moral growth!”

  Ann said quickly, “I did not say that.”

  “But your findings imply it.”

  “No, David, they don’t. I’m discussing the biology, not making evaluative judgments.”

  Allen frowned; Bazargan saw that to him the two were identical. But all the boy said was, “The real question is, can we duplicate the physiological process in humans? Physiological processes are based on proteins, and proteins are genetically encoded. We should be able to splice in the relevant DNA.”

  “Do what?” Gruber said, and Bazargan realized this was the first time the geologist had heard David’s nutty theory.

  Ann said wearily, “David, I told you before. There are no significant genetic differences. Whatever’s happening in the Worlders’ brains is happening with the same input and equipment as ours. Which is why I don’t understand such a different result.”

  David didn’t answer. Instead he looked meditatively out through the arched window. Bazargan knew, as clearly as if the boy had spoken aloud, that he had rejected what Ann had just said. He didn’t believe that shared reality wasn’t tied to a clear, undiscovered genetic sequence. He wanted there to be a stretch of DNA code that could be snipped out and spliced into the human genome. And because he wanted it so badly, he believed it must exist.

  Very dangerous thinking. And not only to Allen himself.

  After a long moment, Allen said, “How can we learn more? If you assume that DNA is the key, then what’s the next step?”

  Ann finally lost all patience. “Dissect a Worlder brain, cut out shared reality, and hardwire it into our own skulls!”

  Bazargan stepped in. He said soothingly, “Ann, what else do we need to know today? Anything else you want to tell us about the Lagerfeld?”

  “I don’t know … oh, yes … no, that’s not important. But … wait … no …”

  “You’re exhausted, my dear,” Bazargan said. But it was Gruber who took action.

  “Come on, Annie,” he said, pulling her up from her pillow, putting an arm around her for support. “When did you eat last, Liebchen?”

  “I don’t remember. Yesterday morning? I’m all right, it was just a passing faintness.”

  “A good reason to eat and sleep,” Gruber said. “’Bye, guys.”

  He led Ann through the archway toward her rooms, his arm still around her waist. David looked after them, frowning. “What gives him the right to make decisions for her?�
��

  “Perhaps she does,” Bazargan said, and instantly regretted it. The boy couldn’t help being irritating, no more than a gnat could help stinging. Bazargan was supposed to be above being bothered by gnats.

  “Please excuse me, David, I think I’m feeling tired myself. This was a useful session, wasn’t it? Does what Ann was saying fit well with your notes on child development in the crelm house?”

  “It fits perfectly.”

  “Good. We all learn more every day. Now, if you’ll excuse me.”

  David got up and left, only a trace of sulkiness around his mouth. Bazargan drew the light curtains across the archways of his room. He had a headache himself, he found.

  He wasn’t in the mood to appreciate that his headache, too, in its own way, came from disjoints in perceived reality.

  Philoctētēs, a celebrated hero of the Trojan War, had both a magic bow that never missed its mark and an oozing, never-healing snakebite that caused him constant pain. The one was the price of the other. Cure the wound and the marksmanship was destroyed.

  But was shared reality, with its elimination of ever being truly separate, the wound or the bow?

  David Allen was sure of the answer. Ahmed Bazargan was not.

  He swallowed a pill for his headache and unrolled his sleeping pallet. In a later version of the Philoctētēs myth, he remembered, Philoctētēs was cured of his snakebite. That was the trouble with these old stories. They mutated over time. You ended up never knowing what to believe.

  Bazargan lay down in the dim room and waited for his headache to pass.

  TEN

  RAFKIT SELOE

  You’re sure that’s what you heard,” Pek Nagredil said.

  “Yes,” Enli said.

  “Wait here.” He disappeared through an archway, leaving Enli standing in his cluttered office, trying to sort out exactly what she was sure of and what she was not.

  The Terrans could do that to you.

  It was not raining this time. On every one of Enli’s other trips to Rafkit Seloe, it seemed to her, it had been raining. Today brilliant sunlight washed through the open windows, bathing everything in soft orange. Ralibib had just come into bloom, and the heavy perfume of the tiny white blossoms, hundreds on each branch, hung on the air. Beneath the ralib bushes, the allabenirib were just finishing. Soon the gardeners would cut the stems back to the ground, readying the plants for their next blooming.

  In the Voratur gardens, a bed of allabenirib had been dug up to make room for Terran rosib.

  Enli reached into an inner pocket of her tunic and took another headpain pill. She was using ten or twelve a day now. Pek Nagredil had told her no more than eight, but eight couldn’t keep the pain at bay. If only this job would be over! Soon, let it be soon …

  When the job was over, the Terrans would die. Because of what she’d overheard, Enli would be the instrument of their death, just as she had been of Tabor’s. Pek Sikorski, who had been so kind to her. Pek Gruber, whom she hardly knew—was it right to judge those one hardly knew? No priest from Reality and Atonement would ever do so; reality judges were always from the local government, familiar with local personalities and circumstances. Pek Bazargan, with his calm, steady face. Pek Allen, certainly crazy but so loving with the children, World and Terran both. And the Terran children, those beautiful small buds …

  Enli squeezed her eyes tightly shut. Another pill? No, she couldn’t, she’d already taken three in just a few minutes, any more would put her to sleep. She couldn’t sleep, she had to make her report. Her head felt so heavy on her neck, the inside of her skull so heavy …

  “Pek Brimmidin.”

  Enli opened her eyes. Pek Nagredil was back with two others, a healer and a priest. Enli tried to bow, stumbled, almost fell over. The servant of the First Flower grasped her arm and led her to a pillow. “Sit down, Pek Brimmidin. Would you like a cup of water?”

  “I—”

  “Bring her pel,” the priest said to Pek Nagredil, who did, looking startled. “Here, drink it all.”

  The pel warmed her a little, dulled her headache a little. Made it at least possible to go on. The pel and the firm warmth of the priest’s hand on her arm.

  “Now, little blossom,” he said kindly, “tell us what you have learned of these Terrans.”

  Enli took one more swallow of pel. “They … . they took a picture of Pek Voratur’s brain.”

  “Yes, so we know,” the priest said. “And we know about the rosib, and about Pek Renjamor’s manufactury and testing of antihistamines, so you needn’t go over that again. In fact, Pek Renjamor has made the first batch of antihistamines and forty people are taking it now, did you know that? All seem cured of their flower sicknesses. The sicknesses were various, although of course mostly to ralibib, since that is the bloom the First Flower blesses us with in this season …” He went on in his soothing kind voice, talking of nothing and everything, giving Enli a chance to collect herself.

  When she had, the priest said, “But there is something more, I think, Pek Brimmidin. Something our other informant has not told us. Perhaps something you learned because you understand the Terran words so much better than any of us.”

  “Yes,” Enli said. She felt her courage returning, flowing back along her veins with the pel. “Yes.”

  “It is dangerous?”

  “Yes!”

  The priest composed his hands in the New Bud pose. “Then I am ready to hear it.”

  “The Terrans … they …”

  “Speak, little flower.” The kindness was still there, but also a note of command.

  Enli said, “They want to cut open the heads of Worlders and take out shared reality, so that it may be put with hard wires into their own heads!”

  Pek Nagredil’s eyes widened. On his face Enli saw the signs of swift pain: the stretched skin around the eyes, the clenched mouth. The healer put both hands to his forehead. Only the servant of the First Flower controlled his headpain, although above his neckfur his skull ridges throbbed. He said, “This is not possible.”

  “Of course not!” the healer cried. “But to even think of it … to be able to think of it! They must be unreal!”

  “Wait,” the priest said. “Pek Brimmidin, you are sure you heard this? From which Terran?”

  “First from Pek Allen,” Enli said. Now that the terrible reality had been shared, she felt her own headache recede slightly. But only slightly. “Then five days ago, all of them discussed it together. I was in the secret place inside the garden wall, which Pek Voratur showed me. It has thin plates for listening to the guest rooms. Of course, everyone knows that traders do such things, but …” Again Enli faltered. But did the Terrans know? If not, that was in itself further proof that they did not share reality. But if they did know, why had they let her overhear their terrible plans?

  “Drink a few more swallows of pel, little blossom.”

  Enli did as the priest said, draining her cup.

  “Now continue.”

  “The Terrans were discussing Pek Voratur’s brain picture. Pek Allen asked if Pek Sikorski had learned enough from the picture to put shared reality into Terrans with hard wires. She said no. She said first she—”

  “Wait,” Pek Nagredil said. “I must ask something. You understand Terran much better than anyone else on World, Enli. But did you understand all the words the Terrans used? Every one?”

  Enli waved her hands. “I thought of that, Pek Nagredil. Over and over. And some of their words were strange to me. But not so many that I could not understand their meaning. And one word I know very well. Pek Sikorski and I use it all the time in her work. It is … is dissect. It means to cut up a plant or animal to learn about it. Pek Sikorski said … she said …”

  The three others waited: the healer and the government official plainly in dread, their mild stolid faces twisted. Only the priest sat calmly, his face filled with sorrow.

  Enli said, “Pek Sikorski told the others she must dissect a Worlder brain to get the sh
ared reality into Terran skulls.”

  The healer cried out. Pek Nagredil briefly closed his eyes, then reached into his waist pouch for a pill. Enli recognized it as the same one she herself was living on these days. Oh, if this job could only be over …

  The healer said violently, “Then that proves it. They are most certainly unreal!”

  “Wait,” the priest said, and everyone fell silent.

  Minutes crept by. Enli felt drowsiness steal over her. So she had taken too many pills. Or maybe it was the pel. Or maybe just the relief of sharing reality with these good people … her people … Tabor had said once …

  A hand shook her. “Not just yet, Pek Brimmidin,” the servant of the First Flower said gently. “A few more questions before you sleep. No, no atonement is necessary, just answer a few more questions. What is the Terran word for floor?”

  Enli gave the word.

  “For brain?”

  She answered.

  “For justice? … For reality? … For the sole cultivation of a private meditation garden?”

  “There is no word for that in Terran.”

  “Is there no word, or have you perhaps not learned the word?”

  “I don’t know,” Enli said.

  “What is the word for a child who has not yet achieved the sharing of reality?”

  “Infant, I think.”

  “Are you sure? Completely sure?”

  “No,” Enli said.

  “How about the word for a bud open enough to see its color but not yet the shape of its petals?”

  The priest went on for twenty or twenty-five more words, asking for the Terran for each. Some Enli knew; many she did not. Her struggle to stay awake made her sit bolt upright on the pillow. Finally she dug her nails into the soft flesh under her upper arm. The priest saw her.

  “That’s enough, little blossom.” He turned to Pek Nagredil and the healer. “She knows much Terran, but there are un-budded places in her knowledge. It is possible, therefore, that she misunderstood what they said. I will certainly tell the High Council what she has reported, but I will not say for certain that it is knowledge in full bloom. The Terran question remains still unanswered.”