The Number Devil: A Mathematical Adventure - Hardcover

Enzensberger, Hans Magnus

Hardcover

ISBN 10: 0805057706 ISBN 13: 9780805057706

Publisher: Metropolitan Books, 1998

Synopsis

The international best-seller that makes mathematics a thrilling exploration.

In twelve dreams, Robert, a boy who hates math, meets a Number Devil, who leads him to discover the amazing world of numbers: infinite numbers, prime numbers, Fibonacci numbers, numbers that magically appear in triangles, and numbers that expand without . As we dream with him, we are taken further and further into mathematical theory, where ideas eventually take flight, until everyone-from those who fumble over fractions to those who solve complex equations in their heads-winds up marveling at what numbers can do.

Hans Magnus Enzensberger is a true polymath, the kind of superb intellectual who loves thinking and marshals all of his charm and wit to share his passions with the world. In The Number Devil, he brings together the surreal logic of Alice in Wonderland and the existential geometry of Flatland with the kind of math everyone would love, if only they had a number devil to teach it to them.

About this title

About the Author

Hans Magnus Enzensberger is the author of many highly lauded books, including Civil Wars: From L.A. to Bosnia. He lives in Munich.

Rotraut Susanne Berner is an illustrator who lives in Heidelberg.

Michael Henry Heim is a prize-winning translator who teaches at UCLA.

Reviews

Grade 6 Up-This book consists of a dozen unusual dreams of Robert, a 12 year old who thinks math is "a waste of time." The number devil who visits him each night changes that with magical demonstrations of mathematical concepts that intrigue the boy. Starting simply with the concept of infinity, the devil introduces prime numbers, square roots, Fibonacci numbers, and more, inventively using coconuts, multiplying rabbits, and other oddities as examples. He demonstrates concepts in imaginative ways that actually make sense, focusing on general principles, with an emphasis on the pleasing consistency of mathematics. Robert becomes interested and is named a "number apprentice" in the final chapter. Building new concepts from those previously learned makes the progression to more complicated areas easier and satisfying. The devil uses made-up terms (e.g., square roots are called "rutabagas") and the author warns that students should learn the correct words. A helpful index identifies these terms, and also reveals the identities of various mathematicians referred to by other names (Johan van de Lune is the "Man in the Moon"). Colorful, cartoon illustrations appear throughout, along with useful tables and diagrams. The dream world recalls Alice's Adventures in Wonderland and Norton Juster's The Phantom Tollbooth (Knopf, 1961), but the attempts at humor and silliness here never match the wit and charm of those classics. Although it is not a fully realized fantasy, The Number Devil may intrigue and teach readers willing to try an unusual introduction to math principles.
Steven Engelfried, West Linn Public Library, OR
Copyright 1998 Reed Business Information, Inc.

Exceptionally handsome four-color illustrations and vignettes deepen the magic of this mathematically minded fantasy, Enzensberger's (Europe, Europe) first book for children. Robert is plagued by bad dreams until a mysterious creature called the Number Devil appears to him one night. Robert, who hates everything to do with numbers, thinks it just another nightmare, but, surprisingly, finds himself fascinated by the intricacies of mathematics as taught by the exacting but always enthusiastic Devil. In a series of 12 dreams, Robert (and the reader) are introduced to ever more complex theories, from different kinds of infinity to triangular numbers. In Number Hell/Number Heaven, Robert and the Devil meet famous mathematicians of the past and Robert is inducted into the ranks of number apprentices. Surreal touches (numbers flying in the air, floating in a swimming pool), fanciful names for mathematical terms (prima-donna numbers for prime numbers) and problems posed directly to the reader contribute to the playful tone. The generous and strategic use of color, however, provides the biggest boost: even mathematical equations look festive here, hand-printed in warm muted tones. Berner's witty spot and full-page illustrations also work to clarify mathematical principles. Many readers, unused to a novel of ideas, may well be daunted by the string of mathematical concepts, particularly because the reasoning behind several of the "tricks" demonstrated by the Devil is only glancingly addressed. But for certain kinds of readers?chess players, puzzle enthusiasts?this will be a favorite. Ages 11-up.
Copyright 1998 Reed Business Information, Inc.

Excerpt. © Reprinted by permission. All rights reserved.

In time Robert grew accustomed to dreaming of the number devil. He even came to look forward to it. True, he could have done without his know-it-all attitude and his temper tantrums--you could never tell when he'd blow up and yell at you--but it was better, so much better, than being swallowed by a slimy fish or sliding down and down into a black hole.

Besides, Robert had made up his mind to show the number devil that he was no fool. You have to put people like him in their place, Robert thought as he got ready for bed one night. The big ideas he has about himself--and all because of a zero. He wasn't much more than a zero when you got down to it. All you had to do was wake up and he was gone.

But to put him in his place Robert had to dream of him, and to dream of him he had to fall asleep. And Robert suddenly noticed he was having trouble doing so. For the first time in his life he lay awake in bed, tossing and turning.

"What are you tossing and turning for?"

All at once, Robert realized his bed was in a cave. There were weird paintings of animals on the stone walls, but he had no time to study them because the number devil was standing over him, twirling his walking stick.

"Rise and shine, Robert!" he said. "Today's our division day."

"Must I?" Robert asked. "You might have at least waited until I was asleep. Besides, I hate division.

"Why?"

"When you add or subtract or even multiply, things come out even. What bugs me about division is that you get this remainder."

"The question is when."

"'When what?"

"When you get a remainder and when you don't. That's what counts. You can tell just by looking at them that some numbers can be divided evenly."

"Right. Like even numbers, which can all be divided by two. No problem. I'm pretty good at threes as well:

9 3

15 3

and so on. It's like multiplying in reverse:

3 x 5 = 15

becomes

15 3 = 5

I don't need a number devil for that. I can do it on my own."

Robert shouldn't have said that. The number devil, his mustache quivering, his nose reddening, his head growing bigger and bigger, jerked Robert out of bed.

"What do you know?" the number devil shouted. "Just because you've learned the multiplication table you think you know all there is to know. Well, you know nothing! Nothing whatsoever!"

There he goes again, thought Robert. First he drags me out of bed, then he hits the ceiling when I tell him I can do division.

"Here I come to a rank beginner out of the goodness of my heart, and no sooner do I open my mouth than he starts making wisecracks! "

"The goodness of your heart!" Robert cried. All things being equal, he would have upped and left, but how do you up and leave a dream? He looked all over the cave, but could find no way to leave.

"What are you looking for?"

"A way out."

"If you go now, you'll never see me again! I'll leave you to choke on Mr. Bockel's pretzel problems, or die of boredom in his class."

Robert knew when he was licked.

"I apologize," he said. "I didn't mean to offend you."

"Good," said the number devil, his anger subsiding as quickly as it had come. "Now, nineteen. Try nineteen. See if you can divide it without a remainder."

Robert thought and thought.

"The only way I can come up with," he said at last, "is to divide it by nineteen. Or into nineteen equal parts."

"Doesn't count," the number devil replied. "It's too easy."

"Or divide it by zero."

"Out of the question."

"Out of the question? Why?"

"Because it's forbidden. Dividing by zero is strictly forbidden."

"What if I did it anyway?"

"Then all mathematics would come apart at the seams!"

He was about to lose his temper again, but he managed to pull himself together.

"Tell me," said the number devil, what would you get if you divided nineteen by zero?"

"I don't know. A hundred, maybe. Or zero. Or anything in between."

"But didn't you say when you were talking about the threes that division was like multiplying in reverse? If that's the case, then

3 x 5 = 15

means that

15 3 = 5

Well, now try that with nineteen and zero."

"Nineteen divided by zero is, say, 19. "

And in reverse?"

"19 times zero ... 19 times zero ... is zero."

"You see? And no matter what number you take, you always get zero. Which means you must never divide a number by zero."

"Okay," said Robert, "I give up. But what do we do with the nineteen? No matter what number I divide it by--two, three, four, five, six, seven, eight, or nine--I get stuck with a remainder."

"Come a little closer," said the number devil to Robert, "and I'll tell you a secret." Robert leaned so close to the number devil that his mustache tickled his ear.

"There are two types of numbers," he whispered. "The garden variety, which can be divided evenly, and the rest, which cannot. I much prefer the latter. You know why? Because they're such prima donnas. From the very first they've caused mathematicians no end of trouble. Wonderful numbers those! Like eleven, thirteen, or seventeen."

Robert couldn't get over how blissful the number devil looked. He might have had a piece of chocolate melting in his mouth.

Copyright 1997 Carl Hanser Verlag Munchen Wien

English translation copyright 1998 Michael Henry Heim

Edition details

• Publisher: Metropolitan Books
• Publication date: 1998
• Language: English
• ISBN 10: 0805057706
• ISBN 13: 9780805057706
• Binding: Hardcover
• Illustrator: Berner Rotraut Susanne
• Edition number: 1
• Number of pages: 260