"That pattern of human conduct which is loosely called "self-respecting" has the curious property of restricting to the individual—through his withdrawal of acts to communicate misfortune—the unfavorable chance occurrences which probability insists must take place. On the other hand, the same pattern of human conduct tends to disseminate and to share chance favorable occurrences among the group. The members of a group of persons practicing "self-respect," then, increase the mathematical probability of good fortune to all their number. This explains the instability of cultures in which principles leading to this type of behavior become obsolete. A decadent society brings bad luck upon itself by the operation of the laws of probability...."Probability and Human ConductFitzgerald
"That pattern of human conduct which is loosely called "self-respecting" has the curious property of restricting to the individual—through his withdrawal of acts to communicate misfortune—the unfavorable chance occurrences which probability insists must take place. On the other hand, the same pattern of human conduct tends to disseminate and to share chance favorable occurrences among the group. The members of a group of persons practicing "self-respect," then, increase the mathematical probability of good fortune to all their number. This explains the instability of cultures in which principles leading to this type of behavior become obsolete. A decadent society brings bad luck upon itself by the operation of the laws of probability...."
Probability and Human ConductFitzgerald
She came very slowly back to consciousness. It was almost as if she waked from utterly exhausted sleep. When she first opened her eyes, they wandered vaguely until they fell upon Calhoun. Then a bitter and contemptuous hatred filled them. Her hand fumbled weakly to the knife at her waist. It was not a good weapon. It had been table-cutlery and the handle was much too slender to permit a grip by which somebody could be killed. Calhoun bent over and took the knife away from her. It had been ground unskillfully to a point.
"In my capacity as your doctor," he told her, "I must forbid you to stab me. It wouldn't be good for you." Then he said, "Look! My name's Calhoun. I came from Sector Med Headquarters to make a planetary health inspection, and some lads in the city apparently didn't want a Med Ship aground. So they tried to kill me by buttering me all over the walls of my ship, with the landing-grid field. I made what was practically a crash landing, and now I need to know what's up."
The burning hatred remained in her eyes, but there was a trace of doubt.
"Here," said Calhoun, "is my identification."
He showed her the highly official documents which gave him vast authority—where a planetary government was willing to concede it.
"Of course," he added, "papers can be stolen. But I have a witness that I'm what and who I say I am. You've heard oftormals? Murgatroyd will vouch for me."
He called his small and furry companion. Murgatroyd advanced and politely offered a small, prehensile paw. He said "Chee" in his shrill voice, and then solemnly took hold of the girl's wrist in imitation of Calhoun's previous action of feeling her pulse.
Calhoun watched. The girl stared at Murgatroyd. But all the galaxy had heard oftormals. They'd been found on a planet in the Deneb region, and they were engaging pets and displayed an extraordinary immunity to the diseases men were apt to scatter in their interstellar journeyings. A forgotten Med Service researcher made an investigation on the ability oftormalsto live in contact with men. He came up with a discovery which made them very much too valuable to have their lives wasted in mere sociability. There were still not enough of Murgatroyd's kind to meet the need that men had of them, and laymen had to forego their distinctly charming society. So Murgatroyd was an identification.
The girl said faintly:
"If you'd only come earlier.... But it's too late now! I ... thought you came from the city."
"I was headed there," said Calhoun.
"They'll kill you—"
"Yes," agreed Calhoun, "they probably will. But right now you're ill and I'm Med Service. I suspect there's been an epidemic of some disease here, and that for some reason the people in the city don't want the Med Service to know about it. You seem to have ... whatever it is. Also you had a very curious weapon to shoot me with."
The girl said drearily:
"One of our group had made a hobby of such things. Ancient weapons. He had bows and arrows and—what I shot you with was a crossbow. It doesn't need power. Not even chemical explosives. So, when we ran away from the city, he ventured back in and armed us as well as he could."
Calhoun nodded. A little irrelevant talk is always useful at the beginning of a patient-interview. But what she said was not irrelevant. A group of people had fled the city. They'd needed arms, and one of their number had "ventured" back into the city for them. He'd known where to find only reconstructions of ancient lethal devices—a hobby collection. It sounded like people of the civil-service type. Of course there were no longer social classes separated by income. Not on most worlds, anyhow. But there were social groupings based on similar tastes, which had led to similar occupations and went on to natural congeniality. Calhoun placed her, now. He remembered a long-out-moded term, "upper middle class" which no longer meant anything in economics but did in medicine.
"I'd like a case-history," he said conversationally. "Name?"
"Helen Jons," she said wearily.
He held the mike of his pocket recorder to pick up her answers. Occupation, statistician. She'd been a member of the office force which was needed during the building of the city. When the construction work was finished, most of the workmen returned to the mother-world Dettra, but the office staff stayed on to organize things when colonists should arrive.
The plague appeared among the last shipload of workmen waiting to be returned to the mother world. There were about a thousand persons in the city altogether. The disease produced, at first, no obvious physical symptoms, but those afflicted with it tended to be listless and lackadaisical and without energy. The first-noticed symptom was a cessation of gripes and quarrelings among the workmen. Shortness of breath appeared two days later. It was progressive. Deaths began in two weeks. Men sank into unconsciousness and died. By the time the transport-ship arrived from Dettra with colonists to be landed ... it was to take back the workmen ... the physicians on the planet were grim. They described the situation by space phone. The transport returned to Dettra without removing the workmen or landing the colonists. The people left in the city on Maris III were self-quarantined, but they expected help.
It was two months before another ship arrived. By then fewer than two hundred of the original thousand remained. More than half those survivors were already listless and short-breathed. A good ten per cent were in the beginning of that marked lethargy which deepened into coma and ended fatally. A desperate, gaunt, plague-stricken few still manned the landing grid.
The ship came down. Men disembarked. There was no crowd to greet them. The survivors still in the city had scattered themselves widely, hoping to escape the contagion by isolating themselves in new and uncontaminated dwelling-units. But there was no lack of communication facilities. Nearly all the survivors watched on vision screens in contact with the landing grid.
The newcomers did not look like doctors, nor act like them. Visiphone contact with the landing grid was immediately broken. It could not be restored. So the isolated groups spoke agitatedly to each other by other visiphone contacts, exchanging messages of desperate hope. Then, new-landed men appeared at an apartment whose occupant was in the act of such a conversation with a group in a distant building. He left the visiphone on as he went to admit and greet the men he hoped were researchers, at least, come to find the cause of the plague and end it.
The viewer at the other visiphone plate gazed eagerly into his friend's apartment. He saw a group of the newcomers admitted. He saw them deliberately murder his friend and the survivors of his family.
Plague-stricken or merely terrified people—in pairs or trios widely separated through the city—communicated in swift desperation. It was possible that there had been a mistake—a blunder; an unauthorized crime had been committed. But it was not a mistake. Unthinkable as such an idea was, there developed evidence that the plague on Maris III was to be ended as if it were an epizootic among animals. Those who had it and those who had been exposed to it were to be killed to prevent its spread among the newcomers.
A conviction of such horror could not be accepted without absolute proof. But when night fell, the public power-supply of the city was cut off—communications ended. The singular sunset hush of Maris III left utter stillness everywhere—and there were screams which echoed among the city's innumerable empty-eyed, unoccupied buildings.
The scant remainder of the plague-survivors fled in the night. They fled singly, carrying the plague with them. Some carried members of their families already stricken. Some helped already-doomed wives or friends or husbands to the open country. Flight would not save their lives. It would only prevent their murder. But somehow that seemed a thing to be attempted.
"This," said Calhoun, "is not a history of your own case. When did you develop the disease ... whatever it may be?"
"Don't you know what it is?" asked Helen hopelessly.
"Not yet," admitted Calhoun. "I've very little information. I'm trying to get more now."
What other information he had he'd gathered from a newly dead man in a field some miles away. He did not mention that at this moment.
The girl went on, exhaustedly. The first symptom was listlessness, of which the victim was unconscious. One could pull out of it with an effort, but one wasn't aware that anything was wrong. The listlessness progressed. One could realize it only by recognizing the more urgent, more violent effort needed to pay attention, and the discovery of weakness when one tried to act. One did not feel discomfort—not even hunger or thirst. One had to summon increasing resolution even to become aware of the need to do anything at all.
The symptoms were singularly like those of a man too long at too high an altitude without oxygen. They were even more like those of a man in a non-pressurized flier whose oxygen supply has been cut off. But such a man would pass out without realizing that he was slipping into unconsciousness. On Maris III the process was infinitely gradual. It was a matter of two weeks or more.
"I'd been infected before we ran away," she said drearily. "I didn't know it then. Now I know I've a few more days of being able to think and act ... if I try hard enough. But it'll be less and less each day. Then I'll stop being able to try."
Calhoun watched the tiny recorder roll its multiple-channel tape from one spool to the other as she talked.
"You had energy enough to try to kill me," he observed.
He looked at the weapon. There was an arched steel spring placed crosswise at the end of a barrel like a sporting blast-rifle. Now he saw a handle and a ratchet by which the spring was brought to tension, storing up power to throw the missile. He asked:
"Who wound up this crossbow?"
Helen hesitated.
"Kim ... Kim Walpole."
"You're not a solitary refugee now? There are others of your group still alive?"
She hesitated again, and then said:
"Some of us came to realize that staying apart didn't matter. We ... couldn't hope to live, anyhow. We ... already had the plague. Kim is ... one of us. He's the strongest. He ... wound up the crossbow for me. He ... had the weapons to begin with."
Calhoun asked seemingly casual questions. She told him of a group of fugitives remaining together because all were already doomed. There had been eleven of them. Two were dead, now. Three others were in the last lethargy. It was impossible to feed them. They were dying. The strongest was Kim Walpole, who'd ventured back into the city to bring out weapons for the rest. He'd led them, and now was still the strongest and—so the girl considered—the wisest of them all.
They were waiting to die. But the newcomers to the planet—the invaders, they believed—were not content to let them wait. Groups and single hunters came out of the city and searched for them.
"Probably," said the girl dispassionately, "to burn our bodies against contagion. They ... kill us so they won't have to wait. And it's just ... seemed so horrible that we ... felt we ought to defend our right to die naturally by ... dying fighting. That's why I ... shot at you. I shouldn't have, but—"
She stopped, helplessly. Calhoun nodded.
The fugitives now aided each other simply to avoid murder. They gathered together exhaustedly at nightfall, and those who were strongest did what they could for the others. By day, those who could walk scattered to separate hiding places, so that if one were discovered, the others might still escape the indignity of being butchered. They had no stronger motive than that. They were merely trying to die with dignity, instead of being killed as sick beasts. Which bespoke a tradition and an attitude which Calhoun approved. People like these would know something of the science of probability in human conduct. Only they would call it ethics. But the strangers—the invaders—the occupiers of the city were of another type. They probably came from another world.
"I don't like this," said Calhoun coldly. "Just a moment."
He went over to Murgatroyd. Murgatroyd seemed to droop a little. Calhoun checked his breathing and listened to his heart. Murgatroyd submitted, saying only "Chee" when Calhoun put him down.
"I'm going to help you to your rendezvous," said Calhoun abruptly. "Murgatroyd's got the plague now. I ... exposed him to it, and he's reacting fast. And I want to see the others of your group before nightfall."
The girl just managed to get to her feet. Even speaking had tired her, but she gamely though wearily moved off at a slant to the hillside's slope. Calhoun picked up the odd weapon and examined it thoughtfully. He wound it up as it was obviously meant to be. He picked up the missile it had fired, and put it in place. He went after the girl, carrying it. Murgatroyd brought up the rear.
Within a quarter of a mile the girl stopped and clung swaying to the trunk of a slender tree. It was plain that she had to rest, and dreaded getting off her feet because of the desperate effort needed to arise.
"I'm going to carry you," said Calhoun firmly. "You tell me the way."
He picked her up bodily and marched on. She was light. She was not a large girl, but she should have weighed more. Calhoun still carried the quaint ancient-type weapon without difficulty.
Murgatroyd followed as Calhoun went up a small inclination on the greater hillside and down a very narrow ravine. Through brushwood he pushed until he came to a small open space where shelters had been made for a dozen or so human beings. They were utterly primitive—merely roofs of leafy branches over frameworks of sticks. But of course they were not intended for permanent use. They were meant only to protect plague-stricken folk while they waited to die.
But there was disaster here. Calhoun saw it before the girl could. There were beds of leaves underneath the shelters. There were three bodies lying upon them. They would be those refugees in the terminal coma which—since the girl had described it—accounted for the dead man Calhoun had found, dead of starvation with food-plants all around him. But now Calhoun saw something more. He swung the girl swiftly in his arms so that she would not see. He put her gently down and said:
"Stay still. Don't move. Don't turn."
He went to make sure. A moment later he raged. Because it was Calhoun's profession to combat death and illness in all its forms. He took his profession seriously. And there are defeats, of course, which a medical man has to accept, though unwillingly. But nobody in the profession, and least of all a Med Ship man, could fail to be roused to fury by the sight of people who should have been his patients, lying utterly still with their throats cut.
He covered them with branches. He went back to Helen.
"This place has been found by somebody from the city," he told her harshly. "The men in coma have been murdered. I advise you not to look. At a guess, whoever did it is now trying to track down the rest of you."
He went grimly to the small open glade, searching the ground for footprints. There was ground-cover at most places, but at the edge of the clearing he found one set of heavy footprints going away. He put his own foot beside a print and rested his weight on it. His foot made a lesser depression. The other print had been made by a man weighing more than Calhoun. Therefore it was not one of the party of plague-victims.
He found another set of such footprints, entering the glade from another spot.
"One man only," he said icily. "He won't think he has to be on guard, because a city's administrative personnel—such as were left behind for the plague to hit—doesn't usually have weapons among their possessions. And he's confident that all of you are weak enough not to be dangerous to him."
Helen did not turn pale. She was pale before. She stared numbly at Calhoun. He looked grimly at the sky.
"It'll be sunset within the hour," he said savagely. "If it's the intention of the newcomers ... the invaders to burn the bodies of all plague victims, he'll come back here to dispose of these three. He didn't do it before lest the smoke warn the rest of you. But he knows the shelters held more than three people. He'll be back!"
Murgatroyd said "Chee!" in a bewildered fashion. He was on all fours, and he regarded his paws as if they did not belong to him. He panted.
Calhoun checked him over. Respiration way up. Heart-action like that of the girl Helen. His temperature was not up, but down. Calhoun said remorsefully:
"You and I, Murgatroyd, have a bad time of it in our profession. But mine is the worse. You don't have to play dirty tricks on me, and I've had to, on you!"
Murgatroyd said "Chee!" and whimpered. Calhoun laid him gently on a bed of leaves which was not occupied by a murdered man.
"Lie still!" he commanded. "Exercise is bad for you!"
He walked away. Murgatroyd whined faintly, but lay still as if exhausted.
"I'm going to move you," Calhoun told the girl, "so you won't be sighted if that man from the city comes back. And I've got to keep out of sight for a while or your friends will mistake me for him. I count on you to vouch for me later. Basically, I'm making an ambush." Then he explained irritably, "I daren't try to trail him because he might not backtrack to return here!"
He lifted the girl and placed her where she could see the glade in its entirety, but would not be visible. He settled down himself a little distance away. He was acutely dissatisfied with the measures he was forced to take. He could not follow the murderer and leave Helen and Murgatroyd unprotected, even though the murderer might find another victim because he was not trailed. In any case Murgatroyd's life, just now, was more important than the life of any human being on Maris III. On him depended everything.
But Calhoun was not pleased with himself.
There was silence except for the normal noises of living wild things. There were fluting sounds, which later Calhoun would be told, from crawling creatures not too much unlike the land-turtles of Earth. There were deep-bass hummings, which came from the throats of miniature creatures which might roughly be described as birds. There were chirpings which were the cries of what might be approximately described as wild pigs—except that they weren't. But the sun Maris sank low toward the nearer hill-crests, and behind them, and there came a strange, expectant hush over all the landscape. At sundown on Maris III there is a singular period when the creatures of the day are silent and those of the night are not yet active. Nothing moved. Nothing stirred. Even the improbable foliage was still.
It was into this stillness and this half-light that small and intermittent rustling sounds entered. Presently there was a faint murmur of speech. A tall, gaunt young man came out of the brushwood, supporting a pathetically feeble old man, barely able to walk. Calhoun made a gesture of warning as the girl Helen opened her lips to speak. The slowly moving pair—the young man moving exhaustedly, the older man staggering with weakness despite his help—came into the glade. The younger helped the older to sit down. He stood panting.
A woman and a man came together, assisting each other. There was barely light enough from the sun's afterglow to show their faces, emaciated and white.
A fifth feeble figure came tottering out of another opening in the brush. He was dark-bearded and broad, and he had been a powerful man. But now the plague lay heavily upon him.
They greeted each other listlessly. They had not yet discovered those of their number who had been murdered.
The gaunt young man summoned his strength and moved toward the shelter where Calhoun had covered an unseemly sight with branches.
Murgatroyd whimpered.
There came another rustling sound. But this had nothing of feebleness in it. Someone pushed branches forthrightly out of his way. He came striding confidently into the small open space. He was well-fleshed, and his color was excellent. Calhoun automatically judged him to be in superlative good health, slightly over-fleshed, and of that physical type which suffers very few psychosomatic troubles because it lives strictly and enjoyably in the present.
Calhoun stood up. He stepped out into the fading light just as the sturdy last-comer grinned at the group of plague-stricken semi-skeletons.
"Back, eh?" he said amiably. "Saved me a lot of trouble. I'll make one job of it."
With leisurely confidence he reached to the blaster at his hip.
"Drop it!" snapped Calhoun, from quartering behind him. "Drop it!"
The sturdy man whirled. He saw Calhoun with a crossbow raised to cover him. There was light enough to show that it was not a blast-rifle—in fact, that it was no weapon of any kind modern men would ordinarily know. But much more significant to the sturdy man was the fact that Calhoun wore a uniform and was in good health.
He snatched out his blast-pistol with professional alertness.
And Calhoun shot him with the crossbow. It happened that he shot him dead.
IV
"Statistically, it must be recognized that no human action is without consequences to the man who acts. Again statistically, it must be recognized that the consequences of an action tend with strong probability to follow the general pattern of the action. A violent action, for example, has a strong probability of violent consequences, and since some at least of the consequences of an act must affect the person acting, a man who acts violently exposes himself to the probability that chance consequences which affect him, if unfavorable, will be violently so."Probability and Human ConductFitzgerald
"Statistically, it must be recognized that no human action is without consequences to the man who acts. Again statistically, it must be recognized that the consequences of an action tend with strong probability to follow the general pattern of the action. A violent action, for example, has a strong probability of violent consequences, and since some at least of the consequences of an act must affect the person acting, a man who acts violently exposes himself to the probability that chance consequences which affect him, if unfavorable, will be violently so."
Probability and Human ConductFitzgerald
Murgatroyd had been inoculated with a blood-sample from the girl Helen some three hours or less before sunset. But it was one of the more valuable genetic qualities of thetormalrace that they reacted to bacterial infection as a human being reacts to medication. Medicine on the skin of a human being rarely has any systemic effect. Medication on mucus membrane penetrates better. Ingested medication—medicine that is swallowed—has greater effectiveness still. But substances injected into tissues or the blood-stream have most effect of all. A centigram of almost any drug administered by injection will have an effect close to that of a gram taken orally. It acts at once and there is no modification by gastric juices.
Murgatroyd had had half a cubic centimeter of the girl's blood injected into the spot on his flank where he could feel no pain. It contained the unknown cause of the plague on Maris III. Its effect as injected was incomparably greater than the same infectious material smeared on his skin or swallowed. In either such case, of course, it would have had no effect at all, becausetormalswere to all intents and purposes immune to ordinary contagions. Just as they had a built-in unit in their digestive tract to cause the instant rejection of unwholesome food, their body-cells had a built-in ability to produce antibodies immediately the toxin of a pathogenic organism came into contact with them. Sotormalswere effectively safe against any disease transmitted by ordinary methods of infection. Yet if a culture of pathogenic bacteria—say—were injected into their blood stream, their whole body set to work to turn out antibodies because all their body was attacked. And all at once. There was practically no incubation-period.
Murgatroyd, who had been given the plague in mid-afternoon, was reacting violently to its toxins by sunset. But two hours after darkness fell he arose and said shrilly, "Chee-chee-chee!" He'd been sunk in heavy slumber. When he woke, there was a small fire in the glade, about which the exhausted, emaciated fugitives consulted with Calhoun. Calhoun was saying bitterly:
"Those characters in the city are immune! They have to be! And they know they're immune, or they wouldn't risk contagion by murdering you or handling the bodies of plague-victims to burn them! So they have to know all about the plague—and they knew it before they arrived! They came because they knew! That's why I shot that man with the crossbow, instead of taking a blaster to him. I meant to wound him so I could make him answer questions, but it's not an accurate weapon and I killed him instead. I got very little from the stuff in his pockets. The only significant thing was a ground-car key, and even that means only there's a car waiting somewhere for him."
The gaunt young man said drearily:
"He didn't come from Dettra, our home planet. Fashions are different on different worlds. His foot-wear was like a style we had on Dettra four years back, and his body-clothing has fasteners we don't use."
Murgatroyd saw Calhoun and rushed to him, embracing his legs with enthusiasm and chattering shrilly of his relief at finding the man he knew. The skeletonlike plague-victims stared at him.
"This," said Calhoun with infinite relief, "is Murgatroyd. He's had the plague and is over it. So now we'll get you people cured. I wish I had better light!"
He counted Murgatroyd's breathing and listened to his heart. Murgatroyd was in that state of boisterous good health which is normal in any lower animal, but amounts to genius in atormal. Calhoun regarded him with satisfaction.
"All right!" he said. "Come along!"
He plucked a brand of burning resinous stuff from the campfire. He handed it to the gaunt young man and led the way. Murgatroyd ambled complacently after him. Calhoun stopped under one of the unoccupied shelters and got out his lab kit. He bent over Murgatroyd. What he did, did not hurt. When he stood up, he squinted at the red fluid in the instrument he'd used.
"About fifteen CCs," he observed. "This is strictly emergency stuff I'm doing now. But I'd say that there's an emergency."
The gaunt young man said:
"I'd say you've doomed yourself. The incubation-period seems to be about six days. It took that long to develop among the doctors we had in the office staff."
Calhoun opened a compartment of the kit, whose minuscule test tubes and pipettes gleamed in the torchlight. He absorbedly transferred the reddish fluid to a miniature filter-barrel, piercing a self-healing plastic cover to do so. He said:
"You're pre-med? The way you talk—"
"I was an interne," said Kim. "Now I'm pre-corpse."
"I doubt that last," said Calhoun. "But I wish I had some distilled water—This is anticoagulant." He added the trace of a drop to the sealed, ruddy fluid. He shook the whole filter to agitate it. The instrument was hardly larger than his thumb. "Now a clumper—" He added a minute quantity of a second substance from an almost microscopic ampule. He shook the filter again. "You can guess what I'm doing. With a decent lab I'd get the structure and formula of the antibody Murgatroyd has so obligingly turned out for us. We'd set to work to synthesize it. In twenty hours, lab time, we ought to have it coming out of the reaction-flasks in quantity. But there is no lab."
"There's one in the city," said the gaunt young man hopelessly. "It was for the colonists who were to come. And we were staffed to give them proper medical care. When the plague came, our doctors did everything imaginable. They not only tried the usual culture tricks, but they cultured samples of every separate tissue in the fatal cases. They never found a single organism—even in the electron microscopes—that would produce the plague." He said with a sort of weary pride, "Those who'd been exposed worked until they had it, then others took over. Every man worked as long as he could make his brain work, though."
Calhoun squinted through the glass tube of the filter at the sputtering torch.
"Almost clumped," he observed. Then he said, "Did you ever hear of a man named Pasteur? One of his first discoveries was that one could get an effectively pure culture of a pathogenic organism by giving the disease to an experimental animal. Better ways were found later, but one still expects a pure culture in a patient who has a disease really badly. What did the lab turn up?"
Kim shook his head.
"Nothing. The bacteriological survey of the planet had been thorough. Oral and intestinal flora were normal. Naturally, the local bacteria couldn't compete with the strains we humans have learned to live with. They couldn't symbiotize. So there wasn't anything unknown. There wasn't any cause of the plague."
Calhoun began to work the filter plunger, by the wavering light of the torch. The piston was itself the filter, and on one side a clear, mobile liquid began very slowly to appear.
"Mutated standard bug? Still, if your doctors did cultures and couldn't reproduce the disease—"
"They could pass it," said Kim bitterly, "but they could never find what carried it! No pure culture would!"
Calhoun watched the clear fluid develop on the delivery side of the filtering piston. The job got done. There was better than twelve cubic centimeters of clear serum on the delivery side, and an almost solid block of clumped blood cells on the other. He drew off the transparent fluid with a fine precision.
"We're doing biochemistry under far from aseptic conditions," he said wryly, "but the work has to be done and we have to take the risk. Anyhow, I'm getting a feeling that this isn't any ordinary plague. A normal pathogenic organism should have been turned up by your doctors."
"It wasn't," said Kim.
"So," said Calhoun, "maybe it isn't one isolatable organism. Maybe the disease-producing mechanism simply isn't there when you make pure cultures of the separate strains of virus and microbe. Murgatroyd was a pretty sick animal. I've only known of one previous case in which atormalreacted as violently as Murgatroyd did. That one had us sweating."
"If I were going to live," said Kim grimly, "I might ask what it was."
"Since you're going to," Calhoun told him, "I'll tell you though you don't. It was a pair of organisms. Their toxins acted synergically together. Separately they were innocuous. Together they were practically explosive. That one was the devil to track down!"
He went back across the glade. Murgatroyd came skipping after him, scratching at the anaesthetic patch on his hide, which he sometimes seemed to notice not because it felt oddly, but because it did not feel at all.
"You," said Calhoun briefly to Helen Jons, "you go first. This is an antibody serum. You may itch afterward, but I doubt it. Your arm, please."
She bared her rather pitifully thin arm. He gave her practically a CC of fluid which—plus blood-corpuscles and some forty-odd other essential substances—had been circulating in Murgatroyd's blood stream not long since. The blood-corpuscles had been clumped and removed by one compound plus the filter, and the anticoagulant had neatly modified most of the others. In a matter of minutes, the lab kit had prepared as usable a serum as any animal-using technique would produce. Logically, the antibodies it contained should be isolated and their chemical structure determined. They should be synthesized, and the synthetic antibody-complex administered to plague-victims. But Calhoun faced a small group of people doomed to die. He could only use his field kit to produce a small-scale miracle for them. He could not do a mass production job.
"Next!" said Calhoun. "Tell them what it's all about, Kim!"
The gaunt young man bared his own arm.
"If what he says is so, this will cure us. If it isn't so, nothing can do us any harm!"
And Calhoun briskly gave them, one after another, the shots of what ought to be a curative serum for an unidentified disease which he suspected was not caused by any single germ, but by a partnership. Synergy is an acting-together. Charcoal will burn quietly. Liquid air will not burn at all. But the two together constitute a violent explosive. This is analogous to synergy. The ancient simple drug sulfa is not intoxicating. A glass of wine is not intoxicating. But the two together have the kick of dynamite. Synergy, in medicine, is a process in which when one substance with one effect is given in combination with another substance with another effect, the two together have the consequences of a third substance intensified to fourth or fifth or tenth power.
"I think," said Calhoun when he'd finished, "that by morning you'll feel better—perhaps cured of the plague and only weak from failure to force yourselves to take nourishment. If it turns out that way, I advise you all to get as far away from the city as possible for a considerable while. I think this planet is going to be repopulated. I suspect that shiploads of colonists are on the way here now—but not from Dettra, which built the city. And I definitely guess that, sick or well, you're going to be in trouble if or when you contact the new colonists."
They looked tiredly at him. They were a singular lot of people. Each one seemed half-starved, yet their eyes had not the brightness of suffering. They looked weary beyond belief, and yet there was not self-neglect. They were of that singular human type which maintains human civilization against the inertia of the race—because it drives itself to get needed things done. It is not glamorous, this dogged part of mankind which keeps things going. It is sometimes absurd. For dying folk to wash themselves, when even such exertion calls for enormous resolution, is not exactly rational. To help each other try to die with dignity was much more a matter of self-respect than of intellectual decision. But as a Med Ship man, Calhoun viewed them with some warmth. They were the type that has to be called on when an emergency occurs and the wealth-gathering type tends to flee and the low-time-sense part of a population inclines to riot or loot or worse.
Now they waited listlessly for their own deaths.
"There's no exact precedent for what's happened here," explained Calhoun. "A thousand years or so ago there was a king of France—a country back on old Earth—who tried to wipe out a disease called leprosy by executing all the people who had it. Lepers were a nuisance. They couldn't work. They had to be fed by charity. They died in inconvenient places and only other lepers dared handle their bodies. They tended to throw normal human life out of kilter. That wasn't the case here. The man I killed wanted you dead for another reason. He wanted you dead right away."
The gaunt Kim Walpole said tiredly:
"He wanted to dispose of our bodies in a sanitary fashion."
"Nonsense!" snapped Calhoun. "The city's infected. You lived, ate, breathed, walked in it. Nobody can dare use that city unless they know how the contagion's transmitted, and how to counteract it. Your own colonists turned back. These men wouldn't have landed if they hadn't known they were safe!"
There was silence.
"If the plague is an intended crime," added Calhoun, "you are the witnesses to it. You've got to be gotten rid of before colonists from somewhere other than Dettra arrive here."
The dark-bearded man growled:
"Monstrous! Monstrous!"
"Agreed," said Calhoun. "But there's no interstellar government, now, any more than there was a planetary government in the old days back on Earth. So if somebody pirates a colony ready to be occupied, there's no authority able to throw them out. The only recourse would be war. And nobody is going to start an interplanetary war! Not with the bombs that can be landed! If the invaders can land a population here, they can keep it here. It's piracy, with nobody able to do anything to the pirates." He paused, and said with irony: "Of course they could be persuaded that they were wrong."
But that was not even worth thinking about. In the computation of probabilities in human conduct, self-interest is a high-value factor. Children and barbarians have clear ideas of justice due to them, but no idea at all of justice due from them. And though human colonies spread toward the galaxy's rim, there was still a large part of every population which was civilized only in that it could use tools. Most people still remained comfortably barbaric or childish in their emotional lives. It was a fact that had to be considered in Calhoun's profession. It bore remarkably on matters of health.
"So you'll have to hide. I think permanently," Calhoun told them. "But in the morning, after I've checked on you people again, I think I'll go into the city and see what I can do about it. Try to rest now. You should all feel much better in the morning."
Kim Walpole said abruptly:
"You've been exposed to the plague. Have you protected yourself?"
"Not yet," acknowledged Calhoun. "Give me a quarter of a CC."
He handed the injector to the gaunt young man. He noted the precision with which Kim handled it. Then he helped get the survivors of the original group—there were six of them—to the leafy beds under the shelters. They were very quiet—even more quiet than their illness demanded. They were very polite. The old man and woman who had struggled back to the glade together made an especial attempt to bid Calhoun good night with the courtesy appropriate to city folk of tradition.
Calhoun settled down to keep watch through the night. Murgatroyd snuggled confidingly close to him. There was silence.
But not complete silence. The night of Maris III was filled with tiny noises, and some not so tiny. There were little squeaks which seemed to come from all directions, including overhead. There were chirpings which were definitely at ground-level. There was a sound like effortful grunting somewhere in the direction of the rampart of hills. In the lowlands there was a rumbling which moved very slowly from one place to another. By its rate of motion, Calhoun guessed that a pack or herd of small animals was making a night-journey and uttering deep-bass noises as it traveled.
He debated certain grim possibilities. The man he'd killed had had a ground-car key in his pocket. He'd probably come out in a powered vehicle. He might have had a companion, and the method of hunting down fugitives—successful, in his case—was probably well established. That companion might come looking for him, so watchfulness was necessary.
Meanwhile—the plague. The idea of synergy was still most plausible. Suppose the toxins—the poisonous metabolic products—of two separate kinds of bacteria combined to lessen the ability of the blood to carry oxygen and scavenge away carbon dioxide? It would be extremely difficult to identify the pair, and the symptoms would be accounted for. No pure culture of any organism to be found would give the plague. Each, by itself, would be harmless. Only a combination of two would be injurious. And if so much was assumed—why—if the blood lost its capacity to carry oxygen, mental listlessness would be the first symptom of all. The brain requires a high oxygen-level in its blood-supply if it is to work properly. Let a man's brain be gradually, slowly, starved of oxygen and all the noted effects would follow. His other organs would slow down, but at a lesser rate. He would not remember to eat. His blood would still digest food and burn away its own fat—though more and more sluggishly—while his brain worked only foggily. He would become only semiconscious, and then there would come a time of coma when unconsciousness claimed him and his body lived on only as an idling machine—until it ran out of fuel and died.
Calhoun tried urgently to figure out a synergic combination which might make a man's blood cease to do its work. Perhaps only minute quantities of the dual poison might be needed—like an antivitamin or an antienzyme, or—
The invaders of the city were immune. Quite possibly the same antibodies Murgatroyd had produced were responsible for their safety. Somewhere, somebody had very horribly used the science of medicine to commit a monstrous crime. But the science of medicine—
A savage idea came to Calhoun. Its practicality might depend on the number of men in the city. But his eyes burned.
He heard a movement across the glade. He reached for his blaster. Then he saw where the motion was. It was Kim Walpole, intolerably weary, trudging with infinite effort to where Helen Jons lay. Calhoun heard him ask heavily:
"You're all right?"
"Yes, Kim," said the girl softly. "I couldn't sleep. I'm ... wondering if we can hope."
Kim did not answer.
"If we live—" said the girl yearningly, and stopped.
Calhoun felt that he ought to put his fingers in his ears. The conversation was strictly private. But he needed to be on guard. So he coughed, to give notice that he heard. Kim called to him across the starlit glade.
"Calhoun."
"Yes," said Calhoun. "If you two talk, I suggest that you do it in whispers. I want to listen, in case the man I killed had friends who'll come looking for him. Did you get his blaster, by the way?"
"Yes," said Kim from the darkness across the way.
"Good!" said Calhoun. "Keep it. And against all medical ethics, I advise you to use it freely if you find suitable targets. But now, just talk quietly if you can."
He settled back. Murgatroyd stirred and cuddled closer against him without wakening. There was the faintest possible murmuring of voices where Kim Walpole and the girl Helen talked wistfully of the possibility of hope.
Calhoun felt very lonely, despite the violent activities he foresaw for the morrow. He almost envied Kim Walpole. But he could not have traded places with him. It wouldn't have been a fair trade. Calhoun was quite confident that—via Murgatroyd—the folk in the glade had a very fair chance of living for some time yet.
His own chances, considering what he had to do, were more nearly zero. Just about zero, when considered dispassionately.
V