“Number Devil” and “Unknown Quantity” present mathematics as flight of fantasy

When does mathematics become a flight of imagination where a prime number is called prima donna, a square root transforms to rutabaga and Pascal’s Triangle becomes a number triangle? It all happens in the Number Devil: A Mathematical Adventure, cleverly and lightly penned by Hans Magnus Enzensberger. The author writes simply and provides exquisite examples while presenting complex—pardon the pun—concepts with deceptive ease.

In this book, the number devil appears each night to a young lad, Robert, in his dreams, and compares the dull world of school learning with the exciting real world of large and small numbers, infinity, zero, one, and many other fun and exciting facets of numbers. For 11 nights, the devil invades Robert’s dreams with rabbits, trees, classmates, and snowflakes to demonstrate various concepts in higher mathematics. Robert’s mother is quite concerned that Robert is feeling ill, but all ends rather well with Robert demonstrating a difficult concept to his very dim teacher. It is quite an astonishing frolic where Robert learns rather quickly and easily—and the reader along with him (which is the whole point: the wonderful flexibility of mathematics). The Fibonacci sequence never looked so yummy, nor so exciting.

Of a more serious note, but equally yummy and exciting is Unknown Quantity: A Real and Imaginary History of Algebra. For those who have moaned and griped about “the new math” for years, algebra isn’t new, and its roots—pardon the pun, again—can be seen at least as far back as 800 B.C. John Derbyshire provides a remarkable mix of history and mathematics, blending them seamlessly and effortlessly. He explains difficult concepts with ease while presenting the gripping and sometimes all-too-brief lives of those who, in his words, “discovered” the properties of mathematics and developed abstractions.

Take time to read the notes at the close of the book. They are very droll, and there is at least one joke that only mathematicians will fully appreciate.

Both of these books, Number Devil and Unknown Quantity, are a lighter look at the world of mathematics. They are undemanding—although I did read Unknown Quantity twice (once for the history and once for the mathematical concepts)—and designed to be starting points in an adventurous journey. Mathematics is fun, flexible, amusing, thought-provoking, and present in our everyday lives. Mathematics is also very sexy. Really.