“But today,” she said, “you were comparing it to a hangover.”

  “How do you know that?”

  She didn’t answer. Such questions had arisen between them before. Unpredictably, but not unseldom, she had an eerily accurate intuition of what was going on in other people’s heads. The psych team, probing every aspect of her mind before they O.K.’d her enlistment, had found indications of some telepathic talent. But that was as hard to pin down and study as most psi phenomena. So Isabel McAndrew was signed on just because she could rapidly assimilate training in advanced linguistics, and because she could cook, sing, organize games, soothe nerves: in general, be the morale officer of what was otherwise a crew of specialists.

  I wonder, though, flashed across her husband’s consciousness. When we get to Tau Ceti, when we’re eye to eye with those beings whose radio we detected (if they have anything like our concept of eyes)—the psych men may well have hoped her gift would serve us better in getting to know them than any number of language courses.

  Then he realized she had not spoken for what was apparently quite some time. He cleared his throat and said: “Don’t get scared, sweetheart. I’m not sick. No headache. Only, well, when I do have a mild hangover, time drags for me. It takes forever to do something, even though the clock says I’m proceeding at my usual speed. I suppose it’s because of being especially aware of my body. Or maybe, I don’t know, maybe the aftermath of alcoholic irritation gears up the brain a little. But anyhow, yes, I do feel sort of like that, now.”

  “Me, too.” Her fingers tightened on him. “It’s been creeping up on me, too. I didn’t mention it for the same reason you didn’t. It looked like such a minor thing. something that’d cure itself. But if we all—!”

  “How can you tell?” McAndrew grinned and patted her cheek. “Never mind. You’ve told me often enough that you don’t know. Probably your subconscious puts different subtle clues together. Come to think of it, when we were last playing bridge with Jerry and Lisette, I did notice their manner was the least bit odd.” Gently, he disengaged her grasp on him and hauled his lanky frame erect. “I’ll check with Doc. Chances are that if this means anything whatsoever, it’s due to environment. They warned us to expect psychological consequences. Doc will prescribe us a pill or a brain stimulation sequence or something, and we’ll be O.K. again.”

  She smiled. He could read the tinge of forlornness underneath. They had more rapport than the other three couples. Theirs was the only love match aboard. The rest got along fine—they’d better!—but the marriages were of convenience. Even in ship’s time, they would take a couple of years to reach Tau Ceti, and then they might spend as much as five years there before returning. So you had to have one woman for each man. And she must meet the same standards as he, of youth, health, skill, and dedication. McAndrew had found his girl for himself, before this expedition was organized, and the luck was fantastic that they both qualified.

  He wanted much to comfort her. The eternal murmur of the vessel, ventilators, pumps, chemical converters, was as eternally underlaid by the bone-deep pulse of the drive. The deck thrust against him with an Earth gravity of acceleration, but metal, not the warm live soil he remembered. The overhead was no sky, the fluoropanel no sun, the ecological plant no forest. Outside this thin skin lay near-total vacuum, seething with hard radiations. Sol was shrunken to another star, ghastly far aft, and now that they had reached some sixty per cent of light speed, Doppler effect made it an ember. The same effect discolored the whole heavens, and aberration was drawing the constellations into distorted clumps. Not easy to ship on the Flying Dutchman!

  But for that exact reason, you dared not confess to fear. You had to keep the tone light. He glanced at the indicator on the door to the bath cubicle, which the four residential cabins surrounded. “Well, whaddaya know,” he exclaimed. “Unoccupied. The first time in recorded history. I better grab while I can.” He popped in. Rather, he tried to, but somehow his body resisted speed.

  Emerging and dressing, he was surprised to note how few minutes had passed. And, for that matter, how quick Isabel was in her turn; for she seemed to be dawdling. While he waited for her, he opened the panel which folded down to make a table and accepted what the autochef sent from the galley. Dinners were ceremonious affairs, cooked by Isabel and eaten in the saloon, but otherwise the couples clung to their privacy. They wanted to remain good friends.

  Her normal breakfast chatter was absent, and he was too worried to jolly her. He swallowed his last coffee in haste and got onto the intercom. “Hullo, Jerry?”

  “Hi,” said Greenberg. who was his scientific assistant as well as the communications officer. The syllable was prolonged.

  “I’ll be late for work. Can you finish that spectroscope-computer linkage alone?” They were gathering a glorious hoard of data, in this place and under these conditions which men had never known before. Hitherto it had kept them cheerful.

  “I…I’m not sure.”

  “Something wrong?”

  “No. Not exactly. But to tell the truth, I’ve been a little off my feed of late. Slow and awkward.”

  McAndrew exchanged a look with Isabel.

  “O.K., then, wait for me,” he said. “I do want to nail down those observations while we’re still in this velocity range, but we’re not accelerating that fast. And what the hell, if we don’t make it, we’ll get another chance coming back.”

  If we come back, said the forbidden part of him.

  He called Vincent Norrington, arranged to see the biologist-physician, kissed Isabel—this time-stretching did have some compensations!—and left. The corridor reached blank and murmurous before him. On the way, he passed Denis Romano, the captain, and Sylvia Norrington, the engineer. Neither of them had any duties while the passage lasted. The Emissary was totally automatic en route: had to be, when such masses and speeds and energies were involved. But they kept busy, maintaining the ecosystem, tinkering improvements into the service equipment, assisting Clarice Romano with her biochemical experiments. Two years in space should not have proved a burden.

  Nonetheless, McAndrew noticed that they looked haggard.

  Norrington, a large and soft-spoken Negro, was already in this consulting room. The bulkheads were paneled in oak, hung with old-fashioned prints, dominated by a stereopic frame which showed moving, ever-changing scenes of Earth. A layout calculated to be restful, McAndrew knew. He wondered if Norrington’s old briar pipe was part of the same act. No one else had wasted any personal baggage allowance on tobacco.

  “Hullo, Arch. Sit yourself. What can I do for you?”

  Norrington blew a leisurely cloud and relaxed into his armchair. “How have you been feeling lately?” McAndrew demanded.

  “Hm-m-m?” Norrington raised his brows. “This is a new twist. I’m supposed to ask you that.”

  McAndrew tautened on the edge of his seat. “I mean it, Doc. I’ve got reason to believe something odd is happening to the bunch of us. Have you noticed anything in yourself?”

  “I see.” Norrington sat quiet a moment, before he opened the console on his desk. Switches, knobs, meters bristled forth. “Suppose you tape an account while I cover my ears,” he said. “Then I’ll do the same, and we’ll play them back.”

  McAndrew nodded. “Good idea.”

  The reports were nearly identical. Even to the slowness of speech.

  The men regarded each other while the walls seemed to grow close. Finally Norrington said, “Let’s test this. Observe the sweep-second hand on my clock here. Count off time for yourself: one hippopotamus, two hippopotamus, and so on. Compare.”

  “I’ve always counted thousand-and-one, thousand-and-two.”

  “If you prefer. I think hippopotamuses are more fun.”

  The results, for both of them, were oddly uneven. McAndrew noted down several series of correlations and averaged them. “The mean discrepancy,” he said, “is about oh-point-two-five. That is, our personal time sense has accelerated by some twenty-five per cent. But why such a large probable error?”

  “Because our biological clocks are out of whack.” Norrington rose. “This apparatus here is only good for routine diagnosis. Come on into the med lab. I want to check you within a centimeter of your soul.”

  Even with the superb automated equipment available—it would later be used to study the unforeseeably alien life forms around Tau Ceti—the process took a couple of hours. They tried to joke meanwhile, but with scant success.

  In the end, Norrington pondered the data printouts for minutes before he said in a flat voice, “Let’s go back to the office.” When they were there, he got out a bottle. “I know how small our liquor supply is,” he said, “but I, at least, need a drink.”

  McAndrew’s hand was not quite steady, taking his glass. “What’s the verdict?” he heard himself ask.

  “Clean.”

  “Huh?”

  “As far as the tests can tell, you’re in virtually perfect shape. A touch of neurological and physiochemical imbalance, but nothing to worry about, obviously a mere by-product of nervous strain due to this time phenomenon. Norrington sipped, put down his glass, stoked his pipe anew, and made an elaborate business of getting it lit. “I’ll have to check everyone, including myself,” he said, “but I’m quite sure the results will be the same.”

  “What can the cause be?”

  Norrington shook his head. “I don’t know.”

  “Our environment—”

  “I doubt that. You remember that volunteer groups spent two years under identical conditions of confinement, noise, vibration, with no ill effects. And the plants and animals on the automatic probes came back in good shape.”

  “But people aren’t animals,” McAndrew protested.

  “Oh, yes, they are,” Norrington said. “I’ll agree, though, the human mind is unique.”

  He scowled and puffed before continuing: “We have to take that into account, always and forever. Remember why a strictly American crew was selected? That made for a lot of grumbling and trouble throughout the Hegemony. Our troops even had to suppress riots, here and there around the world. But the reason was not imperial pride. No, it was only that the psych boys figured there would be enough mental stress without adding intercultural conflict.”

  “So maybe…you mean…the knowledge of how alone we are, that’s causing us to break down?” McAndrew suppressed a shiver. The ultimate betrayal: one’s own self.

  “I do not,” Norrington stated. “Each of us was handpicked for stability. And nothing like this happened while the Solar System was being explored, nor on the Alpha Centauri expedition; and its ship could barely get up to a fourth of our ultimate velocity. No, men in the past have been just as isolated, and a lot less comfortable and safe.”

  “So what is the trouble?”

  “Some new kind of energy field? Maybe you’d better get busy looking.”

  “Nonsense!” McAndrew collected himself. “Sorry. But I can’t see that either.”

  “We’re edging toward the speed of light,” Norrington reminded him. “Men have never gone this fast before. Couldn’t there be some unsuspected effect?”

  “We’ve pushed atoms within a cat’s whisker of c, for centuries, and not found anything but—” McAndrew jarred to a halt.

  “What?” Norrington took the pipe from between his lips and clenched the bowl close to breaking force.

  “Wait a minute.” McAndrew leaned across the desk and scribbled with a stylus on a reusable tablet. How well their loneliness was measured by the fact they couldn’t afford scratch paper. “Damn,” he muttered, “but I wish I’d brought my slide rule…Yeh. Got it.”

  Norrington waited. The bleakness grew and grew in the other man. Finally he spoke:

  “I’ve inverted the time relationship we found. Are we really thinking twenty· five per cent faster? Or are we thinking at our ordinary rate, while everything else has slowed down to eighty per cent of normal?”

  “Is that even a meaningful question?”

  “It sure as hell is. Look, we’ve reached sixty per cent of c. That gives you a tau function of oh-point-eight. In other words, as you well know, if an observer on Earth could see us now, he’d see our clocks, chemical processes, radioactive decay, everything—our time rate—going eighty per cent of his own. Same factor as we’ve observed in ourselves, you and me. I can’t believe that’s coincidence.”

  Norrington’s face turned a peculiarly horrible grayish color. McAndrew saw him sit motionless, as if he were already locked in stasis. The physicist nodded and spat.

  “Yeah. Exactly what you’re thinking. The tau factor approaches zero, faster and faster, as we approach speed of light. We’ll be very close to that in less than five months. What happens to us then?”

  It spoke well for them that they were not shattered by the announcement. They had been worried when Norrington put them through his tests without saying why and McAndrew searched so desperately for a trace of some hitherto unknown physical phenomenon and didn’t find any. The knowledge had become common, after they realized that something must be wrong with everybody, that time had gone askew. But most had thought of…well, psycho-physiology, energy seeping past radiation screens…not this.

  They sat around the saloon table, couple by couple, when Norrington finished and seated himself. Husbands and wives clasped hands, except for the Romanos. The captain doubled both fists together and leaned on them, as if to crumple the tabletop.

  Silence waxed. Weaving beneath it, around it, through it went the relentless rhythm of the ship. And McAndrew imagined crazily that he could hear the unhearable noise beyond the hull, hydrogen atoms dying in the fusion generator or flung aft in one torrent or shuddering with the shock waves of the Emissary’s transit; cosmic rays sleeting through light-years, photons that were old before this galaxy came into being, the synchrotron fury of magnetically whirled electrons. Certainly he felt the pulsations in the metal that enclosed him, and to his awareness they had dropped in frequency, become a bass growl within his flesh. The slugging of his heart, the acrid smell of his fear, were by contrast things of home, human, almost as dear to him as the pressure of Isabel’s fingers.

  “No!” Romano smote the table so it rang. “Impossible!”

  “The truth is never impossible, Skipper,” Isabel said quietly. Because he could have no secrets from her, McAndrew had told her the facts already, and there had been time for her to find some measure of calm. Which had helped him more than he dared reckon up.

  “But your explanation’s absurd,” Romano sputtered. “What you’re saying is that we’re moving at six-tenths c while our brains are sitting still!”

  “Not our brains,” Norrington corrected. “Those are physical organs, subject to the same laws of nature as anything else. Our minds.”

  “You mean the mind is not subject?”

  “Different aspect of natural law,” McAndrew said. “You don’t expect stars to act like molecules, do you? Or men like stones?”

  He took some of the brandy Norrington had ordered set out. “I agree, Denny,” he went on. “It is absurd to suppose that our bodies are moving while our minds are not. There must be some other cause. The fact does appear to be, though, that the human mind is permanently in ordinary cosmic time, and the rate at which it functions is not affected by speed.”

  “Hey, wait!” Jerry Greenberg protested. “Do you mean there is a distinction between subjective and objective time? Everybody knows that. I seem to remember Einstein himself pointed it out. Wasn’t his example the way an hour spent with your best girl on the porch swing is ever so much shorter than an hour spent sitting on a hot stove? O.K., no argument. I can see how our organisms might in some way resent these unnatural conditions and—”

  “No, that is not what I’m getting at,” McAndrew said. “Doc’s tests pretty well rule out physiology or psychology as a cause for this thing. What I mean is that our minds, not our bodies or brains but our minds, are somehow still operating at the same rate as they did on Earth.”

  Greenberg shook his head. “You’re implying that there is one inertial frame of reference which is unique. That was disproved back when the foundations of relativity were first laid.”

  “Not exactly,” McAndrew said. “I’ve given this matter some thought. What we might as well call the cosmic frame does have one peculiarity, namely that most of the accessible physical universe is in it. I mean to say, after all, leaving aside the galactic recession business…throughout an enormous volume of space, not many masses travel at any substantial fraction of light velocity. We had to accelerate to get moving this fast. and we’ll have to decelerate at journey’s end. That takes the problem out of special and into general relativity. The old twin paradox doesn’t arise. When we return to Earth—if we do—no, damn it, when we do!”—he tossed off his drink—“we will in fact be younger than the people who stayed behind.”

  “So?”

  “So there is, strictly speaking one set of inertial frames, not very different from each other, which are indeed unique within any galactic family. The low-velocity set, that all start and planets and interstellar atoms belong to. The cosmic set. Evidently the mind—as opposed to the brain—is somehow tied in to the cosmic set.”

  “Stow that, you two,” Romano barked. “We’ve got a survival problem to lick. Doc, if this goes on, what’ll happen to us?”

  “I’ll tell you straight,” Norrington said. His words lacked tone, and how slowly they fell! “Matters will get worse and worse as the tau factor shrinks. We’ll feel more and more inert, less and less able to coordinate will and action. Only a nuisance, at first. But eventually, for practical purposes, we’ll be stiffened into motionlessness. As far as our perceptions are concerned, that is. We’ll stare at the same object for days, weeks, before we can drag our eyes away, or close them, or anything. We won’t even have any noticeable sensation of interior life, pulse beat, breath, all stopped. It’ll be the most extreme sensory deprivation human beings have ever undergone.” He filled his lungs. “Eleven years of that before we commence deceleration. Forty-eight hours is considered sufficient to induce radical psychosis.”