The Practice Effect by David BrinThe Practice Effect by David Brin

The Practice Effect

byDavid Brin

Mass Market Paperback | January 1, 1995

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From one of the most critically acclaimed and well-loved authors of contemporary science fiction, a highly imaginative and exciting story as only David Brin can write . . . 

“High spirits and inventiveness . . . Dennis's adventures, which can only be called rollicking, are legion.”—Isaac Asimov's Science Fiction Magazine

Physicist Dennis Nuel was the first human to probe the strange realms called anomaly worlds—alternate universes where the laws of science were unpredictably changed. But the world Dennis discovered seemed almost like our own—with one perplexing difference. To his astonishment, he was hailed as a wizard and found himself fighting beside a beautiful woman with strange powers against a mysterious warlord as he struggled to solve the riddle of this baffling world.

“A delightful, often very witty story, with the underlying thoughtfulness we expect from David Brin.”—Poul Anderson
David Brin is a scientist and the bestselling author of Sundiver, The Uplift War, Startide Rising, The Practice Effect, The Postman, Heart of the Comet (with Gregory Benford), Earth, Glory Season, Brightness Reef, and Infinity's Shore, as well as the short-story collections The River of Time and Otherness. He has a doctorate in astroph...
Title:The Practice EffectFormat:Mass Market PaperbackDimensions:288 pages, 6.94 × 4.19 × 0.63 inPublished:January 1, 1995Publisher:Random House Publishing Group

The following ISBNs are associated with this title:

ISBN - 10:055326981X

ISBN - 13:9780553269819

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Rated 5 out of 5 by from Great and weird! This is a zany book! The "practice effect" is a very interesting idea. I was never sure if I wished the world worked that way or if I was glad that it didn't. Great story.
Date published: 2017-07-03
Rated 4 out of 5 by from I liked it This was a fun book and I liked it more than I expected. Even though I have not read to book for a long time, I still remember it fairly well.
Date published: 2017-07-03
Rated 4 out of 5 by from Old story, but very enjoyable I'm hoping there is another book in this universe.
Date published: 2014-03-16
Rated 5 out of 5 by from Old story, but very enjoyable Great fun in the best SF tradition!
Date published: 2013-09-20
Rated 3 out of 5 by from Another alternative universe A zievatron lets Dennis emerge into another Earth where inanimate things become better when they are "practised". But people appear to know nothing about civilisation even if they have very sophisticated tools, apparently. And Lennora, Princess of the L'toff so beautiful. Dennis, the scientist has to wade through this world, trying just to survive, especially since everybody considera him a wizard, and a very powerful one too. Nice book, could have been written in the 50s or 60s, but it is highly enjoyable.
Date published: 2013-09-07

Read from the Book

1   The lecture was really boring.   At the front of the dimly lit conference room, the portly, gray-haired director of the Sahara Institute of Technology paced back and forth—staring at the ceiling with his hands clasped behind his back—while he pontificated ponderously on a subject he clearly barely understood.   At least that’s how Dennis Nuel saw it, suffering in silence in one of the back rows.   Once upon a time, Marcel Flaster might have been one of the shining lights of physics. But that had been long ago, before any of the younger scientists present had ever considered careers in reality physics. Dennis wondered what could ever have converted a once-talented mind into a boring, tendentious administrator. He swore he would jump off of Mt. Feynman before it ever happened to him.   The sonorous voice droned on.   “And so we see, people, that by using zievatronics alternate realities appear to be almost within our reach, presenting possibilities for bypassing both space and time….”   Dennis nursed his hangover near the back of the crowded conference room, and wondered what power on Earth could have dragged him out of bed on a Monday morning to come down here and listen to Marcel Flaster expound about zievatronics.   His eyelids drooped. He began to slump in his seat.   “Dennis!” Gabriella Versgo elbowed him in the ribs, whispering sharply. “Will you straighten up and pay attention?”   Dennis sat up quickly, blinking. Now he recalled what power on Earth had dragged him here.   At seven a.m. Gabbie had kicked open the door to his room and hauled him by his ear into the shower, ignoring his howling protests and his modesty. She had kept her formidable grip on his arm until they both were planted here in the Sahara Tech conference room.   Dennis rubbed his arm just above the elbow. One of these days, he decided, he was going to sneak into Gabbie’s room and throw away all the little rubber balls the redhead liked to squeeze while she studied.   She nudged him again. “Will you sit still? You have the attention span of a cranky otter! Do you want to find yourself exiled even farther from the zievatronics experiment?”   As usual, Gabbie hit close to home. He shook his head silently and made an effort to be attentive.   Dr. Flaster finished drawing a vague figure in the holo tank at the front of the seminar room. The psychophysicist put his light-pen down on the podium and unconsciously wiped his hands on his pants, though the last piece of blackboard chalk had been outlawed more than thirty years before.   “That is a zievatron,” he announced proudly.   Dennis looked at the light-drawing unbelievingly. He whispered, “If that’s a zievatron, I’m a teetotaler. Flaster’s got the poles reversed, and the field’s inside out!”   Gabriella’s blush almost matched the shade of her fiery hair. Her fingernails lanced into his thigh.   Dennis winced, but managed an expression of lamblike innocence when Flaster looked up myopically. After a moment the director cleared his throat.   As I was saying earlier, all bodies possess centers of mass. The centroid of an object is the balance point, where all net forces can be said to come to play…where its reality can be ascribed.   “You, my boy,” he said, pointing to Dennis. “Can you tell me where your centroid is?”   “Umm,” Dennis considered foggily. He hadn’t really been listening all that carefully. “I guess I must have left it at home, sir.”   Snickers came from some of the other postdocs seated around the back of the room. Gabbie’s blush deepened. She sank into her seat, obviously wishing she were elsewhere.   The Chief Scientist smiled vaguely. “Ah, Nuel, isn’t it? Dr. Dennis Nuel?”   Across the aisle, Dennis caught a glimpse of Bernald Brady grinning at his predicament. The tall, beagle-eyed young man had once been his chief rival until managing to have Dennis completely removed from the activity in the main zievatronics laboratory. Brady gave Dennis a smile of pure spite.   Dennis shrugged. After what had happened in the past few months, he felt he had little left to lose.   “Uh, yessir, Dr. Flaster. It’s kind of you to remember me. I used to be assistant director of Lab One, you might recall.”   Gabriella continued her descent into the upholstery, trying very much to look as if she had never seen Dennis before in her life.   Flaster nodded. “Ah, yes. Now I recollect. As a matter of fact, your name has crossed my desk very recently.”   Bernald Brady’s face lit up. Clearly, nothing would please Brady more than if Dennis were sent on a far-away sample-collecting mission…say, to Greenland or Mars. So long as he remained, Dennis presented a threat to Brady’s relentless drive to curry favor and climb the bureaucratic ladder. Also, without really wishing to be, Dennis seemed to be an obstacle to Brady’s romantic ambitions for Gabriella.   “In any event, Dr. Nuel,” Flaster continued, “you certainly cannot have ‘left’ your centroid anywhere. I believe if you check you’ll find it somewhere near your navel.”   Dennis looked down at his belt buckle, then beamed back at the Director.   Why, so it is! You can be sure I’ll keep better track of it in the future!   “It’s disappointing to learn,” Flaster said, affecting a hearty tone, “that someone so adept with a makeshift sling knows so little about center of mass!”   He was clearly referring to the incident a week ago, at the staff formal dance, when a nasty little flying creature had come streaking in through a window, terrorizing the crowd around the punch bowl. Dennis had removed his cummerbund, folded it into a sling, and flung a shot glass to bring down the batlike creature before it could hurt someone seriously with its razor-sharp beak.   The improvization had made him an instant hero among the postdocs and techs and got Gabbie started on her present campaign to “save his career.” But at the time all he had really wanted was to get a closer look at the little creature. The brief glimpse he caught had set his mind spinning with possibilities.   Most of those present at the dance had assumed that it was an escaped experiment from the Gene-craft Center, at the opposite end of the Institute. But Dennis had other ideas.   One look had told him that the thing had clearly not come from Earth!   Taciturn men from Security had quickly arrived and crated the stunned animal away. Still, Dennis was certain it had come from Lab One…his old lab, where the main zievatron was kept…now off limits to everyone but Flaster’s hand-picked cronies.   “Well, Dr. Flaster,” Dennis ventured, “since you bring up the subject, I’m sure we’re all interested in the centroid of that vicious little varmint that buzzed the party. Can you tell us what it was, at last?”   Suddenly it was very quiet in the conference room. It was an unconventional thing to do, challenging the Chief Scientist in front of everybody. But Dennis didn’t care anymore. Without any apparent reason the man had already reassigned him away from his life’s work. What more could Flaster do to him?   Flaster regarded Dennis expressionlessly. Finally he nodded. “Come to my office an hour after the seminar, Dr. Nuel. I promise I will answer all of your questions then.”   Dennis blinked, surprised. Did the fellow really mean it?   He nodded, indicating he would be there, and Flaster turned back to his holosketch.   “As I was saying,” Flaster resumed, “a psychosomatic reality anomaly has its start when we surround a center of mass by a field of improbability which…”   When attention had shifted fully away from them, Gabriella whispered once more in Dennis’s ear. “Now you’ve done it!” she said.   “Hmm? Done what?” He looked back at her innocently.   “As if you don’t know!” she bit. “He’s going to send you to the Qattara Depression to count sand grains! You watch!”