home books THE PRACTICE EFFECT sample chapters


by David Brin

sample chapters

The Practice Effect

Sooee Generis: 5

"Which law? you sonova —" Dennis pounded on the door.
          He stopped. It was useless. By now the sending probe had activated. He was already on the anomaly world — already on...
          Dennis stared at the blank door. He felt behind himself and sat heavily on one of the crates. Then, as his situation soaked in, he suddenly found himself beginning to laugh! He couldn't stop. His eyes filled as he gave in to the giddy feeling.
          No one had ever been as cut off as he was, cast from Earth to a faraway world.
          People might read about adventures in faraway places, but the truth was that most, at the first hint of anything truly dangerous, would dig a hole and cry out for Mother.
          As an initial reaction, then, perhaps laughter wasn't bad. At least he felt more relaxed afterward.
          From a crate nearby, the pixolet watched, apparently fascinated.
          I'm going to have to come up with a new name for this place, Dennis thought as he wiped his eyes. Flasteria just won't do.
          The initial crisis of isolation had passed. He was able to look to his left, to the other door, the only one that would now open — onto another world.
          Brady's talk of a "different set of physical laws" continued to bother Dennis. Brady had probably just been trying to get to him. Even if he was telling the truth, it would have to be something pretty subtle, since biological processes were so compatible on both worlds.
          Dennis remembered a science-fiction story he had once read in which a minute change in electrical conductivity resulted in a tenfold increase in human intelligence. Could it be something like that?
          Dennis sighed. He didn't feel any smarter. The fact that he couldn't remember the story's title sort of refuted that possibility.
          The pixolet glided from its perch to land on his lap. It purred, looking up at him with emerald eyes.
          "Now I'm the alien," Dennis said. He picked up the little native. "How about it, Pix? Am I welcome? Want to show me around your place?"
          Pix squeaked. It sounded eager to be off.
          "Okay," Dennis said. "Let's go."
          He strapped on his tool belt, with the needle gun holstered to one side. Then, taking an appropriate "explorerlike" stance, he pulled the lever to unlock the far door. There was a hiss of equalizing pressure, and his ears popped briefly. Then the hatch swung open to let in the sunshine of another world.

Cogito, Ergo Tutti Fruitti: 1

The airlock rested on a gentle slope of dry, yellow grass. The meadow fell away toward a green-rimmed watercourse a quarter mile sway. Beyond the stream, rows of long, narrow hills rose toward whitecapped mountains. Swards of yellow interspersed unevenly with carpets of varitone green.
          Yes, they looked like real trees, and the sky was blue. White cirrus clouds laced across the almost cyan vault overhead.
          For a long moment it was eerily, unnaturally quiet. He realized he had been holding his breath since opening the door. It made him feel lightheaded.
          Inhaling, he tasted the crisp, clean air. The breeze brought sounds of brushing grass and creaking branches. It also brought odors... the unmistakable mustiness of chlorophyll and humus, of dry grass and what smelled like oak.
          Dennis stood in the air-lock's combing and looked at the trees. They sure looked like oak. The countryside reminded him of northern California.
          Could this place actually be Earth? Dennis wondered. Had the ziev effect played another trick on them all and given them teleportation rather than an interstellar drive?
          It would be amusing to hitchhike to a pay phone and call Flaster with the news. Collect, of course.
          Dennis felt a sharp stab as tiny claws bit into his shoulder. The pixolet's wing membranes snapped wide with a sound like a shot, and the creature soared off over the meadow, toward the line of trees.
          "Hey... Pix! Where are you..."
          Dennis's voice caught in his throat as he realized this couldn't be Earth. This was where Pix came from.
          He began noticing little things — the shape of the leaves of grass, a huge, fernlike plant by the riverside, a feeling in the air.
          Dennis made sure his holstered sidearm was unencumbered, and his boot cuffs well covered by his gaiters. The dry grass crunched beneath his feet as he stepped out. Tiny, whining insect sounds filled the air.
          "Pix!" he called, but the little creature had flown from sight.
          Dennis moved cautiously, all senses alert. He guessed the first few moments on an alien world could be the most dangerous of all.
          Trying to watch the sky, the forest, and the nearby insects all at once, he didn't even notice the squat little robot until he tripped over it and fell sprawling to the ground.
          Dennis instinctively rolled away into a crouch, the needler suddenly in his hand, his pulse pounding in his ears.
          He sighed as he recognized the little Sahara Tech exploration drone.
          The 'bot's cameras tracked him with a barely discernible whir. Its observing turret slowly turned. Dennis lowered the needler. "Come here," he commanded.
          The robot seemed to consider the order for a moment. Then it approached on spinning treads to halt a meter away.
          "What have you got there?" Dennis pointed.
          The robot held something in one of its manipulator grips. It was a shiny bit of metal, with a clawed pincer at one end.
          Isn't that a piece of another robot?" Dennis asked, hoping he was wrong.
          Compared with some of the sophisticated machines Dennis had worked with, the exploration 'bot wasn't very bright. But it understood a basic vocabulary. A green light on its turret flashed, indicating assent.
          Where did you get it?"
          The little machine paused, then swiveled and pointed with one of its other sampling arms.
          Dennis got up and looked, but he saw nothing in that direction. He moved cautiously through the tall grass until, at last, he came to a flat area partly hidden by the weeds. There he stopped and stared.
          The clearing looked like a wilderness parts store... a Grizzly Adams wrecking yard... a rustic electronics swap meet.
          One — no, two — S.I.T. robots had been rather tactlessly disassembled; their parts lay in neat rows among the clumps of grass, apparently ordered and sorted by size and shape.
          Dennis knelt and picked up a camera turret. It had been ripped out of its housing, and the pieces had been laid out on the ground, like merchandise for sale.
          The trampled mud was strewn with scattered bits of straw, wire, and glass. Dennis looked closer. Here and there, mixed in among the tread marks and the torn pieces of plastic machinery, were faint but unmistakable footprints.

          Dennis looked down at the neat rows of gears, wheels, panels, and circuit boards — at the faint marks in the clay — and all he could think of was an epitaph he had once read in a New England cemetery.
          I knew this would happen someday.
          Dennis had always felt he was somehow destined to encounter something really unusual during his life. Well, here it was in front of him — tangible evidence of alien intelligence.
          The comforting Earthlike Gestalt finished evaporating around him. He looked at the "grass" and saw it wasn't like any grass he had ever seen. The line of trees was now a dark, unknown forest filled with malign forces. Dennis felt a crawling sensation on the nape of his neck.
          A clicking sound made him whirl, the needler in his hand. But it was only the surviving robot again, poking through the pieces of its disassembled fellows.
          Dennis picked up an electronics board from the ground. It had been pried out of its housing by main force. It could easily have been separated with just a twist, but it had been roughly sheared away, as if the entity doing the dissection had never heard of threaded sleeves or bolts.
          Was this the work of primitives, then? Or someone from a race so advanced that they'd forgotten about such simple things as screws?
          One thing was certain. The being or beings responsible didn't have a high regard for other people's property.
          The robots had been made mostly of plastic. He noted that most of the bigger metal pieces seemed to be missing entirely.
          Dennis suddenly had a very unpleasant thought. "Oh, no," he murmured. "Please, don't let it be!" He rose with a feeling of numb dread in the pit of his stomach.
          Dennis walked back to the airlock. He rounded the corner and stopped suddenly, groaning out loud.
          The access panel to the zievatron return mechanism lay ajar. The electronics cabinet was empty; its delicate components lay on the ground, like pieces on display on a store shelf. Most were clearly broken beyond repair.
          With an eloquence borne of irony, Dennis simply said "Argh!" and sagged back against the wall of the airlock.
          Another epigram floated around in the despair that seemed to fill his brain — something a friend had once said to him about the phenomenology of life.
          "I think, therefore I scream."

Cogito, Ergo Tutti Fruitti: 2

The robot "peeped" and played the sequence over again. Dennis concentrated on the three-day-old images displayed on the machine's tiny video plate. Something very strange was going on here.
          The small screen showed shapes that looked like blurry humanoid figures moving around the zievatron airlock. The beings walked on two legs and appeared to be accompanied by at least two kinds of quadrupeds. Beyond that, Dennis could hardly make out any detail from the noisy enlargement.
          The miracle was that he could see anything at all. According to its inertial recorder, the robot had been on a distant ridge, several kilometers away, when it detected activity back at the airlock and turned to photograph the shapes clustered about the zievatron portal. At that distance, the robot shouldn't have been able to see anything at all. Dennis suspected something was wrong with the 'bot's internal tracker. It must have been closer than it thought it was at the time.
          Unfortunately, this tape was almost his only source of direct information. The records of the other 'bots had been ruined when they were so rudely disassembled.
          He skimmed over the robot's record to a point about three days ago, when it all seemed to have begun.
          The first to arrive at the airlock was a small figure in white. It rode up upon the back of something like a very shaggy pony — or a very large sheepdog. Dennis couldn't decide which simile was more appropriate. All he could make out about the humanoid was that it was slender and moved gracefully as it inspected the zievatron from all angles, hardly touching it at all.
          The figure in white sat before the airlock and appeared to begin a long period of meditation. Several hours passed. Dennis skimmed the record at high speed.
          Suddenly, from the forest verge, there erupted a troop of mounted natives charging toward the airlock on shaggy beasts. In spite of the blurriness of the image, Dennis could sense the first intruder's panic as it bounded to its feet, then hurriedly mounted and rode off, bare meters ahead of its pursuers.
          Dennis saw no more of the figure in white. But as one detachment of the newcomers gave chase, the rest came to a halt by the airlock.
          Most of these humanoids seemed to have large, furry heads, distended high above the shoulders. In their midst there dismounted a smaller, more rotund biped in red wrappings, who approached the airlock purposefully.
          Try as be might, Dennis couldn't make the images resolve any clearer.
          By this time, the robot had apparently decided that all this activity merited closer attention. It began descending the hill to return to base and get a closer look. In moments it had dropped down to the level of the trees, and the action at the zievatron was lost from view.
          Unfortunately — or perhaps fortunately — the little 'bot moved slowly over the rugged terrain. By the time it got back, the creatures had already finished their dissection of the Earth machines and departed.
          Perhaps they were in a hurry to help pursue the figure in white.
          Dennis let the recording play itself out again. He sighed in frustration.
          It had been so tempting, on looking at those blurry shapes, to interpret them as humans. Yet he knew he had better not go into things with any preconceived notions. They had to be alien creatures, more closely akin to the pixolet than to himself.
          He slipped the record disk out of the robot and replaced it with a blank one.
          "You're going to have to be my scout," he ruminated aloud in front of the little drone. "I guess I'll want to send you ahead to find out about the inhabitants of this world for me. Only this time I'll want you to put a high priority on stealth and your own survival. You hear? I don't want you taken apart like your brothers!"
          The little green assent light on the probe's turret lit up. Of course, the 'bot couldn't really have understood all that. Dennis had been mostly talking to himself, to gather his own thoughts. He would parse the instructions in carefully phrased Robot-English later, when he had worked out exactly what he wanted the little machine to do.
          He faced a real problem, and he still wasn't quite sure what he could do about it.
          Sure, Brady had given him "... almost enough gear to build another damned zievatron..." But practicality was quite another thing. No one had imagined he would need to bring along spare power cables, for heavens sake! Both of the big, high-voltage copper busses had been shredded out at the roots, along with most of the detachable metal in the electronics bay.
          Even if he did try to build and calibrate another return mechanism, would Flaster keep the zievatron tied up long enough to let him finish? Dennis felt he understood the S.I.T. chief pretty well. The fellow was anxious for a success to further his ambitions. Dennis might even be cast loose so Lab One could be put to work searching for another anomaly world!
          And even if he tried to reassemble the device, would he be left alone by the natives long enough to finish?
          Dennis picked up the one alien artifact he had found — a sharp, curve-bladed knife that had fallen into the high grass and apparently been lost by the vandals.
          The long, tapered blade had the smooth sharpness of a fine razor, yet it was almost as flexible as hard rubber. The grip was designed for a hand smaller than his, but it was obviously meant to be comfortable and provide a firm grasp.
          The butt was carved in what appeared to be the shape of a dragon's head. Dennis hoped that wasn't what the natives actually looked like.
          He couldn't fathom what the thing was made of. It was certainly doubtful a better knife could be manufactured on Earth. It seemed to belie the idea that the natives were primitives.
          Perhaps the vandals were the local equivalent of criminals or careless children. (Could the chase he had observed have been some sort of game, like hide-and-go-seek?)
          What had happened here might be atypical of their society as a whole. Dennis tried to be optimistic. All he really needed was some metal stock and a couple of days in a good machine shop to fix and calibrate some of the larger ruined parts. The knife seemed to indicate the natives had a high enough technology.
          They might even know many things men of Earth did not. He tried to be optimistic, and imagined being the first Earthling to make friendly contact with an advanced extraterrestrial culture.
          "I might be able to trade my pocket nailclipper-stopwatch for a genuine gompwriszt or a K'k'kglamtring," he mused. "I could be wealthy in no time!... Ambassador Nuel. Entrepreneur Nuel!"
          His morale lifted just a little. Who could tell?
          The sun was setting in a direction Dennis decided to call west. A tall range of mountains covered that horizon, stretching around to the south and then eastward around this high valley. Sunlight glanced off numerous small glaciers. There were bright highlights from a winding river that weaved through the southeastern mountains.
          Dennis watched the reflections from the distant river. The beauty of this alien twilight took some of the sting out of being stranded on a strange world.
          Then he frowned.
          Something was wrong with the way the river ran through the hills. It seemed to rise and fall... rise and fall....
          It's not a river, he realized at last.
          It's a road.

Cogito, Ergo Tutti Fruitti: 3

Nothing could bring home the tangibility of a world better than trying to dig a hole in it. Exertion, the clank of metal against earth, sweat smell and the musty, dry dust of abandoned insect nests all verified the reality of the place like nothing else ever could.
          Dennis leaned on his spade and wiped perspiration. Hard work had broken his numb reaction to the shocks of the day before. It was good to be active, doing something about his situation.
          He scattered dirt around the flat mound, patting it down, then covered the cairn with a scattering of grass.
          He couldn't take most of his supplies with him on his journey. But locking them in the airlock wouldn't do either. Leaving as much as a gram inside would prevent the people back at Lab One from sending another envoy.
          He had used electrical tape to write a message on the side of the lock, telling where his detailed report was buried with the equipment.
          Still, if he knew Flaster and Brady, they would dither a long time before deciding on a follow-up mission, Realistically, Dennis knew if anyone was going to fix the return mechanism it would be himself. He couldn't afford any more slip-ups.
          He had already made one big mistake. This morning, when he had opened the airlock and stepped out into the misty dawn, he found that the robot was gone. After an hour of worried searching, he realized that the little drone had departed during the night. He found its tracks leading westward.
          It must have set out on the trail of the humanoids — apparently to find out all it could about them, pursuant to instructions.
          Dennis cursed himself for thinking aloud in the robot's presence the day before. But honestly, who would have expected the machine to accept orders in anything but prim Robot-English? It should have rejected the commands as too flexible and inspecific!
          He hadn't even given the robot a time limit. It would probably stay out until its tapes were full!
          The 'bot must have a wire loose somewhere. Brady wasn't kidding when he said something had gone flaky with the machines they had sent here.
          Now Dennis had lost two companions since coming to this world. He wondered what had become of the pixolet.
          Probably it was back in its own element, glad to be away from the crazy aliens who had captured it.
          As the golden-white sun rose above the eastern treeline, Dennis made ready to go. He would make do alone.
          He had to tie knots in the straps of his backpack to keep them from slipping. Apparently Brady had bought the cheapest equipment possible. Dennis muttered comments on his rival's probable parentage as he hoisted the pack and set off southeastward toward the road he had seen the day before.

Cogito, Ergo Tutti Fruitti: 4

Dennis hiked along narrow game paths, always watching out for possible dangers. But the forest was peaceful. In spite of the squeaky noises from his awkward pack, he found himself enjoying the sunshine and the fresh air.
          He took bearings as well as he could with the cheap compass Brady had provided. When he took breaks by the banks of small streams he kept up a notebook on the ways this world differed from home. So far the list was brief.
          The vegetation was very Earthlike. The predominant trees in this area looked a lot like beech, for instance.
          It could be a sign of parallel evolution. Or the zievatron might open onto alternate versions of Earth itself. Dennis knew as much about the ziev effect as anybody back home did. But he admitted that that wasn't all that much. It was a very new field.
          He kept reminding himself to move with caution. Still, as the forest became more familiar, he found himself passing the time playing with the anomaly equations m his head, trying to find some explanation.
          The animals of the forest watched suspiciously from cover as a preoccupied Earthman hiked their narrow paths in the direction of morning.
          When evening finally came, Dennis camped under the trees by a brook. Not wanting to risk a fire, he tinkered with the rickety little gas stove Brady had provided. A weak flame finally sputtered to life and he was able to stir up a lukewarm batch of freeze-dried stew.
          I'll have to start hunting soon, he realized. The favorable biochemistry report notwithstanding, Dennis was still uncomfortable with the idea of shooting any local creatures. What if the "rabbits" here were philosophers? Could he be so sure anything he aimed at wasn't intelligent?
          When the tepid meal was done, Dennis activated his camp-watch alarm. It was no bigger than a deck of cards, with a small display screen and a tiny rotating antenna. He had to tap it several times to get it started.
          Apparently Brady had been saving Sahara Tech money again. "It may give me two seconds' warning if something the size of an elephant comes rooting through my pack," Dennis sighed.
          With the needler by his side, he laid back in his sleeping bag and watched through the gaps in the branches overhead as the constellations came out. The configurations were utterly alien.
          That finished off the parallel Earth theory once and for all. Dennis scratched three lines of equations from his mental chalkboard.
          While waiting for sleep to come, he watched the sky and named the constellations.
          Toward the southern mountains. Alfresco the Mighty wrestled with the great snake, Stethoscope. The hero's piercing eyes shone unevenly, one red and twinkling, the other bright green and steady. The green eye might be a planet, Dennis decided. If it moved over the next few nights, he would give it a name of its own.
          Above Alfresco and Stethoscope, the Chorus of Twelve Virgins sang backup to Cosell the Loquacious as he chanted a monotonous description of Alfresco's mighty struggle. It didn't matter that the combatants hadn't budged in millennia. The announcer found color to fill out the time.
          Overhead, the Robot rolled, squat and imperturbable upon a highway made up of a billion tiny numbers, pursuing the Man of Grass... the Alien.
          Dennis stirred. He wanted to look at the destination the Man of Grass so doggedly sought. He wanted to turn his head. But he finally realized, with the complacency that comes in dreams, that he had been asleep for some time.

Cogito, Ergo Tutti Fruitti: 5

He came to the road late in the afternoon of his fourth day.
          His journal bulged with notes on everything from trees to insects, from rock formations to the local varieties of birds and snakes. He had even tried to drop rocks from a cliff, to time their fall and measure the local force of gravity. Everything seemed to support the idea that this place was not Earth but was an awful lot like it.
          About half the animals seemed to have close cousins back home. The other half were unlike anything he had ever seen.
          Already Dennis felt he was becoming a seasoned explorer — like Darwin or Wallace or Goodall. And best of all, his boots were beginning to wear in.
          He had hated them at first. But after the initial painful blisters, they seemed to become more comfortable day by day. The rest of the equipment still caused him aggravation, but he seemed to be getting used to the stuff, gradually.
          The camp-watch still awakened him several times every night, but he apparently was getting the hang of its tiny controls. It no longer went off every time a leaf blew through his camp.
          Last night, though, he had started awake to see a troop of hairy-hoofed quadrupeds skirting the edge of his camp. They stared into the beam of his flashlight while his heart pounded. Then they scampered off.
          On reflection they had seemed harmless enough, but why hadn't the alarm warned him?

          Dennis's equipment worries dropped from his mind as he eagerly skidded down the last gravelly slope to the highway. He dropped his pack and approached to kneel by the shallow curb.
          It was an odd road, barely wide enough for a small Earth landcar to pass. Uneven and twisty, it followed the contours of the land instead of cutting straight through, as a highway on Earth would have done. And its edges were ragged, as if no one had bothered to trim them when the bed was laid.
          The shiny pavement felt smooth and yet tough. Dennis scuffed it and walked a few paces. He tried to scratch it with a metal buckle and dribbled water from his canteen. It seemed skidproof and weatherproof, and offered resilient traction.
          Two narrow grooves — exactly one point four two meters apart — ran down its center, following every twist and turn. Dennis knelt to peer into one of the thin channels, its cross section a near-perfect semicircle. The inside surface was almost slippery smooth to the touch.
          Dennis sat down on a nearby stump, whistling softly to himself.
          This road was a very advanced artifact. He doubted a surface like it could be made on Earth.
          But why the ragged edges? Why the grooves, or the twisty inefficient path?
          It was perplexing, like the illogical way in which the return mechanism and the robots had been taken apart. The locals seemed to think differently than men.
          Back at the airlock, Dennis had found most of the metal parts taken away from the zievatron. He thought this might mean he had arrived on a metal-poor world. But in the past few days he had seen at least three areas where iron and copper ores lay open and available.
          It was a mystery. And there was only one way to find out more.
          To the west, the road climbed higher into the mountains. Eastward, it seemed to descend into a broad watershed. Dennis picked up his pack and started off along the road, away from the afternoon sun — toward what he hoped would be civilization.

Cogito, Ergo Tutti Fruitti: 6

It wasn't an easy idea to get used to, but Dennis was coming to the conclusion that he had misjudged Bernald Brady.
          The night after encountering the highway, Dennis thought about it as he stirred a pot of soup over his little stove.
          Perhaps he had been unfair to his old S.I.T. nemesis. During his first few days on this new world, he had complained a lot about the quality of his equipment, blaming Brady for his blisters, his chafed shoulders, and his tepid meals. But those problems had all abated with time. Obviously he had needed time to adapt. Brady and the equipment must have merely been a convenient set of scapegoats for his initial misery.
          Now that he had apparently found the knack, the little stove seemed to work just fine. Its first fuel canister had been used up in a day. But the second had lasted much longer and heated his food better. All it seemed to have taken was a bit of practice. That, he confessed a bit immodestly, and a little mechanical aptitude.
          While the soup cooked, Dennis examined the little camp-watch alarm with new respect. It had taken him days, but he had finally found out that the colors of the little lights on its screen corresponded roughly with the carnivority of the creatures nearby. The correlation had been made clear when he witnessed a pack of foxlike creatures stalking a covey of small birds and watched the counterparts on the screen. Maybe it had to do with body temperature, but somehow the alarm had distinguished the two separate groups clearly into red and yellow dots on the screen.
          It bothered Dennis a little that it had taken him so long to notice all this. Perhaps he had spent too much of the journey playing with equations in his head.
          Anyway, the trip would be over soon. All this day he had passed signs of quarrying in the surrounding hills. And the road had broadened somewhat. Soon, perhaps tomorrow, he knew he would come upon the creatures who ruled this world.
          The camp-watch hummed in his hands, and its little antenna suddenly swung about to point westward. The pale screen came alight and an alarm began to buzz softly.
          Dennis cut off the sound and reached over to draw the needler from its holster. He turned off the stove. When its faint sigh died away, Dennis could hear only the soft, rustling wind in the branches.
          The forest night was a thick maze of black shadows. Only a few wan stars winked overhead through a thickening overcast.
          A small cluster of tiny dots appeared in the lower left corner of the camp-watch screen. They formed a twisting band, snaking slowly toward the center of the screen.
          Finally he heard faint creakings, and soft snorting sounds in the distance.
          The points on the screen sorted themselves into colors. Over a dozen large yellow dots moved along in a procession, apparently following the path of the highway.
          Yellow was the color he had learned was assigned for herbivores. Interspersed among the yellow points were a large number that glowed pink, and even bright red. And in the center of the procession were two tiny green lights. Dennis had no idea what those meant.
          Trailing some distance behind the end of the procession, there followed another small green pinpoint.
          His camp was uphill from the road a bit. He laid the watch-alarm aside and moved carefully downslope. The night seemed to amplify the snap of every twig as he tried to move silently toward a better vantage point.
          After a brief wait, a faint glow appeared to his left. It brightened, then became a painful, piercing white light, spearing through the trees by the road.
          Headlights! Dennis blinked. Now, why does that surprise me? Did I think the makers of a road like this one wouldn't be able to illuminate it?
          Hidden by the undergrowth, he squinted against the bright beam. Vague figures marched behind it, bipedal, with swinging arms.
          The procession passed below his blind. He heard the low chuffing snorts of beasts. Shading his eyes, he made out giant quadrupeds pulling hulking vehicles that slid soundlessly along the road. Each conveyance sent a bright beam spearing ahead of it into the gloom.
          Behind each came a formation of striding bipeds. Dennis caught glimpses of heavy, coweled clothing and what seemed to be sharp, glinting weapons, held at high port.
          But each time his night vision began to return, another giant sled came around the corner to the west, its bright beam dazzling him and sending him flat against the ground again. It was frustrating, but there didn't seem to be any way to get a better look!
          More of the swaggering, coweled figures passed, then more quadrupeds, pulling hulking, eerily silent wagons. Dennis tried to make out how they moved. He neither heard nor saw any turning wheels. Yet hovercraft would give out blasts of compressed air, wouldn't they?
          Antigravity? Nothing else seemed to fit. But if that was so, why were they using animal power?
          Could these be descendants of some fallen civilization, patching their commerce together with rude fragments of their forefathers' science? It seemed to fit what he observed.
          The idea of antigravity excited Dennis. Might that be the difference in physical laws Brady had talked about during those last moments on Earth?
          A last troop of the hooded "warriors" passed below. These rode rather than walked. Their mounts tossed thickly maned heads and nickered, seeming to him so much like shaggy ponies that Dennis mistrusted his observation. It would be too tempting to interpret what he saw in Terran terms.
          He rubbed his eyes and stared. But silhouettes were all he could make out.
          One animal among the riders carried a smaller figure, coweled in a cleat of faded white — standing out in the deep gloom outside of the headlights. Something he saw in the smaller entity's carriage told him that this one was a prisoner. It carried no shiny weapons, and its arms lay motionless on the animal's neck. The hooded head slumped forward dejectedly.
          As the riders passed below, the white-hooded prisoner's head lifted, then started to turn as if to look up into the undergrowth where he was hiding! Dennis ducked down, feeling his throat suddenly go dry.
          One of the dark silhouettes ahead turned around in its saddle and pulled on a tether. The prisoner's mount stumbled forward, and the party passed below.
          Dennis blinked and shook his head to clear it. For a moment, in the glare and confusion, he had experienced a queer illusion. It had seemed to him that the prisoner's white cloak had opened — for a brief, timeless instant — and the starlight had shown him the sad, forlorn face of a beautiful girl.

Cogito, Ergo Tutti Fruitti: 7

For a long while the image lingered in his brain — so long, in fact, that Dennis hardly noticed the end of the procession.
          He felt a bit lightheaded. Yeah, that must have been it. Too much excitement had gotten him seeing things.
          Dennis watched the last glimmer of the caravan pass around the far bend to the east. He still knew next to nothing about the technology and culture of the locals. All he had learned was that the natives shared some of humanity's less savory habits — such as the way they treated one another.
          A moment later a tiny mutter of sound drifted up from the road below.
          Dennis suddenly remembered the image on the camp-watch display. There had been one more tiny green dot, following the caravan from behind. In all the excitement he had forgotten about it!
          He crept forward to get a better view. There were no more bright, blinding lights. Now he might get a good look!
          He slid quietly to within feet of the road itself. At first he saw nothing. Then a tiny noise made him look to the right.
          A glint of glass and plastic reflected the faint glow of the departing procession. A tiny articulated arm waved in the dim starlight. On almost silent, spinning treads, the Sahara Tech exploration robot whizzed down the alien highway eastward... following Dennis's instructions to the letter.
          ... finding out about the natives.
          Dennis barely stifled a shout. Idiot machine! He rushed out onto the highway, tripping over a tree root and rolling most of the way. He made it to his feet in time to see the robot, one of its arms waving as if in farewell, pass around the bend and out of sight.
          Dennis cursed softly but soundly. That robot's tapes doubtless carried all the information he needed. But he couldn't chase it or call out without bringing himself to the attention of the caravan guards!
          He was still muttering softly, standing there in the middle of the dark road, when something alive dropped onto his head from an overhanging branch. Dennis gasped in alarm as the thing wrapped itself tightly over his eyes, sending him stumbling, reeling into the trees.

Cogito, Ergo Tutti Fruitti: 8

"What was the big idea, scaring me half to death?" Dennis accused hoarsely. "I might have run into something and hurt both of us!"
          The object of his ire watched him from a rock a few feet away, green eyes gleaming in the light from the camp stove. The pixolet yawned complacently, apparently of the opinion Dennis was making a big deal out of nothing.
          "Damn all machines and natives! Just where have you been the past four days, anyway? Here I rescue you from a fate worse than boredom at the hands of Bernald Brady, and in return all I ask is a friend who knows the neighborhood. What happens? That 'friend' up and leaves me all alone, until isolation eventually gets me so I'm talking to myself... or worse, to a stubby little flying pig who can't understand a word I'm saying...!"
          Dennis found he could hold his hands steady at last. He poured a cup of soup for himself. Blowing on it, he muttered as his temper slowly wound down. "Stupid, practical joking E.T.s... damned fickle aliens..."
          He glanced over his cup at the diminutive native animal. Its tongue was hanging out. Its eyes met his.
          Dennis let out a sigh of surrender. He poured some soup into the overturned pot cover. The pixolet hopped over and lapped at it daintily, looking up at him from time to time.
          When both had finished, Dennis rinsed out the utensils and crawled back into his sleeping bag. He picked up the camp-alarm and worked on its settings. Pix leaped over beside him and watched.
          Dennis tried to ignore it but couldn't maintain his ire for long — not with it looking at him that way, purring, watching with apparent fascination the adjustments he made to the little machine.
          Dennis shrugged and picked up the small creature. "What is it about you and machines? You sure can't use them. See?"
          He shook its little paws. "No hands!"
          With the stove turned off, the forest night settled in around. In a little island in the quiet, Dennis soon found himself telling the pixolet about the constellations and all the other things he had discovered.
          And he realized it was good to have company again, even if it was an alien creature who didn't understand a single word he said.

THE END of these sample chapters

The Practice Effect

about this book

In THE PRACTICE EFFECT physicist Dennis Nuel is the first human to probe the strange realms called anomaly worlds — alternate universes where the laws of science are unpredictably changed. But the world Dennis discovers seems almost like our own — with one perplexing difference.

Copyright © 1984 by David Brin. All rights reserved.

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DAVID BRIN scientist

a brief intro to author David Brin


David Brin's science fiction novels have been New York Times Bestsellers, winning multiple Hugo, Nebula and other awards. At least a dozen have been translated into more than twenty languages. They range from bold and prophetic explorations of our near-future to Brin's Uplift series, envisioning galactic issues of sapience and destiny (and star-faring dolphins!).
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Short stories and novellas have different rhythms and artistic flavor, and Brin's short stories and novellas, several of which earned Hugo and other awards, exploit that difference to explore a wider range of real and vividly speculative ideas. Many have been selected for anthologies and reprints, and most have been published in anthology form.
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David Brin's Ph.D in Physics from the University of California at San Diego (the lab of nobelist Hannes Alfven) followed a masters in optics and an undergraduate degree in astrophysics from Caltech. Every science show that depicts a comet now portrays the model developed in Brin's PhD research.
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Brin's non-fiction book, The Transparent Society: Will Technology Force Us to Choose Between Freedom and Privacy?, continues to receive acclaim for its accuracy in predicting 21st Century concerns about online security, secrecy, accountability and privacy.
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Brin speaks plausibly and entertainingly about trends in technology and society to audiences willing to confront the challenges that our rambunctious civilization will face in the decades ahead. He also talks about the field of science fiction, especially in relation to his own novels and stories. To date he has presented at more than 200 meetings, conferences, corporate retreats and other gatherings.
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Brin advises corporations and governmental and private defense- and security-related agencies about information-age issues, scientific trends, future social and political trends, and education. Urban Developer Magazine named him one of four World's Best Futurists, and he was cited as one of the top 10 writers the AI elite follow. Past consultations include Google, Microsoft, Procter & Gamble, and many others.
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