It did not terrify Cantrell to know he was up so high and going so fast, going higher and faster than any human before him. He would be up even higher the next day, he remembered, going so high and so fast he would not come down again.

It would be a shame to leave Earth, he knew. There was security in her firmness, with no great space underfoot through which to drop down, down, down. Up here there was emptiness all around. Emptiness and, except for the dull throb of the rocket engines, silence. Out there—he looked up—there would be a greater emptiness, a greater silence, an infinity of nothingness in all directions.

He felt suddenly cold at the thought, and then shame swept over him, forcing the paralysis aside. Fear of the unknown again, he thought distastefully. No matter how much the psychologists tried, they could not erase that icy prickling sensation that came with its contemplation. They were all children when it came to space, kids frightened by the dark alleys of the universe, fearing the bogey man that waited lurking in the velvet depths through which no one had passed before. Probably they would find nothing out there to fear, nothing at all, and yet the feeling would go on and on, whenever men had to face the unknown, whenever they had to force themselves whistling past silent graveyards that contained only the fear of fear.

With swift precision he pressed studs on the control panel before him, and a bank of jets on the side of his rocket flared into sudden life, pushing, turning, pulsing flame into the thin air of the outside. His gyro-chair made an effortless compensation for the altered direction. The ship banked, leveled, then leaped forward on a new course. Cantrell smiled. He could handle the ship now as though it were a part of him. On the big leap he expected no trouble.

Not so the planners, who refused to leave the minutest stone unturned in their search for flaws in man or rocket. Physical checkups were made as often as twice a day. Psychiatrists had analyzed him constantly during the past six months, probing for any hidden factors that might make a space flight futile, fearing perhaps a mental return to the womb for a security that could not be found in untraveled space. We're all children when it comes to space, he reminded himself, and he laughed and wondered half-seriously if he were really as psychologically free as he thought he was—excepting his animal allergy of course, which was insignificant. There were many facets of the human mind the clinical instruments of psychology could never hope to touch; the mind was like an iceberg, and the submerged nine-tenths could hold a great many unfathomables hidden in the vast depths, subtle monstrosities waiting to spring out and claw at his sanity.

He smiled grimly, as he realized where his thoughts were leading him. To fear of the unknown again. Of course, it was only the intellectual contemplation of it, but the mere thought disturbed him, and he began to feel angry at himself for allowing the thoughts to exist at all.

Irritably he jabbed at the controls and felt the reassuring thrusts that drove him gently into the heavy-padded cushions of the seat. With a smile, this time of satisfaction, he watched the speedometer needle rise to a new height. Below him, Earth was an unfamiliar blur, and he touched off the braking rockets to look at it.

The landscape took on more familiar features, with its surface pockmarked by the ravages of wind and rain, its broad fields stretching out in all directions like the fur on some great animal. He failed to suppress a shudder of disgust at that last thought. He'd be glad to get off Earth, onto the moon where he would be alone for awhile and away from the unpleasantnesses of ordinary life. These past months, with Jarvis and his dogs, the psychiatrist's incessant questioning—

The radio said into his ears: "Okay, Cantrell, that's enough of a workout. Bring her in and report to HQ. Colonel Enders wants a word with you."

"Right," Cantrell said into a microphone. He switched off the radio and muttered: "Damn Colonel Enders. What's he want this time, to check the nipples on my beer bottles?"

Angrily, he flipped the rocket into a soundless dive that reached screaming proportions as he entered heavier atmosphere. The outer metal glowed, and the temperature rose in the controlroom. He twisted the rocket onto a tail of flame and settled.

"And that's that—until tomorrow," he told himself.

He threw switches to inactivate the motors and looked out an observation window. A fast-moving jeep curved across the stretch of sand towards him. Behind the jeep a dog came running; at the sight of the animal, Cantrell felt nausea tug at him. He reached for the radio.

He said into it, "Control? Get that damned dog off the field."

"Sorry," Control said, "I'll contact the jeep. One of Captain Jarvis' dogs got loose, and—"

"I'm not interested in your excuses," Cantrell said angrily, "and I don't care if it does belong to Captain Jarvis. Get it off the field, or I'll blast it off!" Irritably, he cut communications.

He looked out the window. The jeep had stopped, and someone had gotten out and was walking back to collar the dog and return it. The jeep started up again.

Cantrell breathed a sigh of relief. He felt annoyed with himself, as he always did when something like this happened, but the self-condemnation failed to placate him. Damn it! Jarvis was a psychiatrist; the man knew how these things affected him. To make matters worse, it was Jarvis' dog. Probably trying another of his "experiments", Cantrell thought disgustedly.

He crawled out of the airlock and down the long metal stairs to the ground. The jeep pulled up, and the khaki-clad driver said, "Sorry about the dog, sir, but—"

"Skip it," Cantrell snapped, climbing into the jeep. "Just take me to HQ."

The soldier nodded and spun the jeep around. They went flashing toward a fat clump of buildings that squatted alone at the edge of the landing field.

As Cantrell had expected, Captain Jarvis was with Colonel Enders in the latter's office.

"What was the idea of sending out that mongrel," Cantrell flared. "You know I'm allergic to animals."

"It was an accident. Besides, you're not allergic to anything," the psychiatrist said calmly, ignoring the insult to his pet. "You're rationalizing a pathological fear—"

"Now, see here—"

Captain Jarvis held up a placating hand "—or hatred, if you wish, of animals."

"Okay, okay, I don't like animals," Cantrell said. "We've been over that a dozen times. So what? I suppose you still think it has some bearing on my going to the moon and back?"

The psychiatrist shrugged. "Who knows? It might have."

Colonel Enders said, "I'm beginning to agree with Cantrell, Captain. We're not going to find anyone perfect, it seems, so we may as well take those with the best qualifications. Cantrell certainly isn't going to encounter animals in space, and there's no life on the moon; our foremost scientists assure us of that."

"But can you be sure," the psychiatrist wondered, "can they be sure, can anybody be sure? Scientists don't have all the right answers about our Earth, much less the other planets; we know as much about Earth as a flea knows about the dog or the cat he's on."

Cantrell grimaced at the analogy. "That's why we're going up, to find a few answers. Anyway, tomorrow I'll be on my way because I've got the qualifications for it, animals or no animals. And if the moon has creatures on it that resemble dogs or cats or even fleas, I'll be mighty surprised. How about you, Colonel?"

"Don't drag me into your arguments, Cantrell," the Colonel sighed. "I'm a military man, not a scientist. Both the Earth and the moon may be green cheese for all I know. The main thing I'm interested in is that you get up there and back safely."

"I will," Cantrell promised.

"I hope you do," Captain Jarvis said earnestly. "I'm not trying to heap obstacles in your path, Cantrell. It's just that we know so little about anything that even an 'allergy' like yours might be a hazard. Suppose up there, for example, it suddenly took on cockeyed proportions and went to lesser animals; suppose a fly accidentally got aboard the rocket, you might even open a hatch to get away from it—and forget to put on your spacesuit."

"Thank the fates I'm not a military man, Jarvis, and can speak freely," Cantrell said dryly. "You already know I don't like you, and I'm beginning to like you even less."

"Come, come," Colonel Evans said hastily, "there's no point in arguing. We can't get perfection, I'm afraid. Cantrell here's the closest to our qualifications we could get, physically and psychologically, consistent with the right background for the job. Tomorrow at noon the rocket's going to take off with Cantrell aboard, and then we'll know."

"Yes," the psychiatrist said steadily, "and then we'll know."

Cantrell turned to Colonel Evans. "Will that be all, Colonel?"

Evans glanced hastily at Jarvis and nodded. "That's it, I guess—until tomorrow at noon."

"Right," Cantrell said. "See you." And he went out.

Once outside in the warm afternoon sun he mentally damned Jarvis and Evans, classifying them both as incompetents who drew military salary for putting red-taped impediments in the way of progress; the rocket should have taken off months ago.

He shrugged, trying to content himself with the thought that tomorrow he'd be away from them, away floating in the pure emptiness of space. Even so, the mere thought of Jarvis irritated him, made his fingers itch for the man's throat; him and his talk of animal fears!

Okay, so he hated animals, well he had good reason to. Ever since that dog had attacked him when he was a child, he'd hated dogs; and then the hatred spread to other animals—why not, for they all were potentially dangerous—and sometimes it even made him sick to think of them. It made sense when you stopped to consider it carefully. He'd moved to the city, to the great steel canyons that imprisoned only specimens of humanity, and for years never saw an animal. Now, he was in the open again, in the great desert and the plains. But there were no animals, only the dogs Captain Jarvis insisted on keeping.

"Nuts to Captain Jarvis," he said.

The next morning he felt the same way. He was called into HQ for last minute instructions that were the same as those laid out months ago. Cantrell knew them by memory, but the excitement of the impending blastoff prevented his being bored or even from being annoyed by the psychiatrist's inevitable presence. Now there was nothing to prevent the leap of the Earthbound into space; not even Jarvis could delay it now.

The jeep drove Jarvis, Evans and Cantrell to the waiting rocket. They got out.

Evans offered his hand. "Good-bye, Cantrell, come back in one piece."

"Sorry I was so hard on you, Cantrell," Jarvis said, extending his hand. "I hope you make it okay."

Cantrell nodded and took the man's hand. "Thanks. I expect to."

He climbed the ladder to the airlock door and stood there for a moment watching the jeep carry its passengers across the field to a safe distance. Then he went inside and strapped himself into the seat.

"Okay, Cantrell," Control said. "Blast off when ready."

"Right," Cantrell said into the radio. He closed the airlock door and checked pressure gauges. "In ten seconds," he said, activating the firing mechanism. Mentally he counted: ten, nine, eight, seven....

The rocket shuddered, and Cantrell found himself pressed suddenly into the seat. In the viewscreens Earth spun dizzily away from him. After a few minutes the push ceased and weightlessness began.

"Everything okay, Cantrell?" the radio said, after awhile. It was Evans.

"Fine, Colonel," Cantrell said. "Not a dog or a cat in sight."

"Can you see Earth?"

Cantrell manipulated dials, activating the lower television eyes. "There she is," he said. "Looks real impressive. I can see nearly all of North America now and a good part of the Pacific. The land looks queer from up here,"—he frowned—"something like—" He broke off, staring. "Like—"

"Like what?" Jarvis' voice demanded suddenly. "It looks like what, Cantrell?"

Cantrell shook his head bewilderedly. "Nothing," he said uncertainly. He felt a sudden irritation that Jarvis couldn't let him alone even with so much of space intervening. "It looks like I'm going to make it to the moon, that's all."

"You were going to say something else, Cantrell, what?"

"Let him alone, Jarvis," Evans whispered; "he's got enough to worry about."

"That's right," Cantrell said irritably, "and I'm going to worry about it in silence." He reached for the radio switch.

"But, Cantrell—" Evans said. Then the radio went dead.

Cantrell grinned and watched Earth getting smaller below. The grin faded as he thought of his almost-spoken comparison of a few minutes before, of the land resembling the shriveled skin of an animal. Jarvis would have made much of that, of course, with his psychiatric ramblings. Yet, the comparison was disturbing just the same. Why did he torture himself?

He regarded Earth skeptically, hoping to subdue the irrational thoughts. Certainly the shape was not that of an animal. At least not an Earth animal. But then it wouldn't have to be, he reminded himself—and felt doubly irritated at the reminder. It looked very different from the globes he'd seen picturing the planet. It looked almost—alive. From this height, great forests resembled tiny hairs, mountain ridges and canyons were skin blemishes and pores; the great oceans looked like giant mouths, open and hungry.

Cantrell laughed nervously. It was ridiculous. Yet the more he looked, the more Earth receded below him, the more the resemblances increased. He stared at the planet. It was ridiculous, but there were even several portions below that looked like great eyes staring at him. As he watched, one blinked.

Cantrell screamed. The sound was shrill in the narrow control chamber. Then he cursed and felt ashamed.

"I'm going crazy," he told himself. His voice was hoarse. "Jarvis was right."

But the thought failed to help. The sudden feeling of terror was still with him, and he found himself trembling. It was only a cloud, he told himself, only a cloud passing over a section of land that from this distance looked like an eye. He tried to laugh away the fear, but the sound stuck in his throat. He felt his heart beating faster than it should.

"No," he said desperately, looking away, "no, I'm okay. My mind is clear, and I'm all right. It's just being up here that gives a guy the jitters. Fear of the unknown. Things look different when you're not close to them. Got to calm down. Take it easy."

His hands trembled.

"Scientists don't have all the right answers even about our Earth here," Jarvis had said. "We know as much about Earth as a flea knows about the dog or the cat he's on."

The words echoed in Cantrell's memory, and he forced himself to look down at Earth. It was a planet, that was all, an inanimate mass and nothing more. "... as much as a flea knows ..." But was it possible that a flea might not realize the animal he was on was an animal?

He had a headache, and he shook his head in an effort to clear it. His vision blurred, refocussed with astounding clarity. Lines flowed together with sudden meaning. Before his gaze rivers became veins, eyes stared at him curiously, ocean-mouths yawned. The truth burst upon him then, with a sudden flash that drove his blood coursing through his body, with a realization that jerked him as though he had been struck with a whip. He laughed insanely at the thought, and the laughter exploded in the narrow cabin and flowed over him in torrents, echoing.

He was the only one in the world who could see things as they really were. He was as certain of that as he was of his own existence. He knew now, and his was the only knowledge: Earth was a space animal, the humans parasites like fleas on a cat or a dog. And the Earthlings didn't know, they didn't even suspect!

The radio buzzed. He pressed a button.

"Cantrell," Evans' harassed voice came. "This is an order: maintain contact at all times, until the moment you set foot back on Earth. Understand?"

Cantrell laughed with his strange secret knowledge. "I'm not coming back," he said happily. He was the only one who could escape this animal, the only one, and he felt elated at this, felt a sense of power he'd not known. "I'm not going to be a parasite crawling on the back of an animal." The thought sickened him, and he gagged.

"Cantrell!" It was Jarvis. "Cantrell, listen to me—"

"No," Cantrell said. "You listen to me."

And he told them about Earth being a space-animal. His mind rebelled at the thought, but he forced himself on for he wanted Jarvis to suffer down there, he wanted them all to suffer with the knowledge of what they were. Where was their pompous self-importance now, their flea's dream of conquering the universe?

"He's crazy," Evans whispered.

"Cantrell, listen to me," Jarvis said.

But Cantrell was staring in horrified fascination at Earth dwindling below, at the space-animal watching him. "No!" he cried. "No, it's too late." And he shut off the radio and ripped the wires from their moorings.

Ahead of him lay the moon. He switched screens to look at it. It was chalky and pockmarked, like the skin of a diseased animal. Great iridescent veins glowed through its body. From a crater bed a great baleful eye regarded him.

Cantrell screamed again and frantically pressed studs on the control panel. The rocket shot flame from its side tubes and turned in a short arc, swinging the moon from sight. The forward viewscreens showed the stars now, and beyond them an infinite blackness.

"I'll be safe out there," Cantrell told himself.

The rocket leaped forward.

"You were right," Evans said bitterly, putting down the radiophone with a gesture of helplessness. "Now, what do we do?"

Jarvis shrugged. "Start over," he said. "What else is there to do? Find someone else to pilot another rocket."

"Someone without Cantrell's hallucinations," Jarvis ammended.

"And pray that they were hallucinations," Jarvis amended further.

Evans looked at him sharply. "What do you mean?"

Jarvis said calmly, "My favorite theme, Colonel—simply that we don't know much about this blob of matter we're on. One factor disturbs me: while Cantrell was afraid of animals, he never imagined he saw them. Outside of his one idiosyncrasy, he was a very sound person."

"What are you getting at?" Evans demanded irritably.

"That it's unfortunate Cantrell had this animal fear; it's much too easy to blame that for what he saw. As a psychiatrist, I suppose I should say that's the reason for it; I might be right. But it has also occurred to me I might be rationalizing." He leaned forward, intensely serious. "Suppose, just suppose for a minute that maybe we're the ones who are wrong, that maybe we're really parasites on an alien organism, that maybe we're under a kind of mass auto-hypnosis to protect our pride, and that maybe space restores our sanity—for awhile anyway, until another form of insanity takes over."

"Anyone who supposed that would be crazy," Evans blurted.

"Perhaps," Jarvis admitted, "but who's to tell? I wonder, does the flea know the true nature of the dog, or does he think he's living on some kind of world built just for him?"

Evans sputtered, searching for words. Finally he managed, "See here, Captain, this is nonsense, and I order you to stop such talk immediately."

Jarvis sighed. "I hope so, Colonel, I really hope it is nonsense. Man is a proud animal; it's interesting to consider how such knowledge would affect him." He shrugged helplessly and turned to leave the room. "At any rate, the only way to find out is to send up another man in another rocket and hope he doesn't report the same thing; if he does, we'll just blame it on one of his psychological quirks, and try again. But for all we know about this universe, Earth might be a space-animal, a type of life so close to us and yet so alien we don't even recognize it—or don't want to!"

Colonel Evans wet his lips. "Do you—do you really believe that, Captain?"

Jarvis considered the question. "No," he said slowly. "No, I don't. But I do think it points up an important fact. When a man gets out there in space, cut off from everything he's ever known, allergies, idiosyncrasies, personal likes and dislikes—everything on a conscious and a subconscious level may take on an exaggerated importance."

"You make it a big problem," Evans said.

"It is a big problem," Jarvis sighed. "At any rate, I'm going to volunteer for the next flight. That's the least I can do for Cantrell." He went out.

The Colonel stared after him, puzzled and slightly indignant. He shook his head. The man was crazy. Earth an animal—the idea was preposterous. But the thought hammered at him, repeating. Jarvis was right, of course, when he said it was undoubtedly psychological. And yet suppose—just suppose....

Trembling, he shook off the thought and looked out at the field, the buildings, the sky, Earth's pale satellite emerging from the sky like a child following in the wake of its mother. They say the moon came out of Earth, he thought suddenly, and the analogy struck home. The man in the moon looked down at him, and he turned hastily away.

The afternoon was warm, but Colonel Evans suddenly felt very cold.