Computers and the Imagination: Visual Adventures Beyond the Edge by Clifford Pickover (St. Martin's Press, 1991) is Pickover's third second book about computers and recreational mathematics. Like its predecessor Computers, Pattern, Chaos and Beauty and its successor Mazes for the Mind, Pickover gives the purposes of the book as being to present novel ways of representing complicated data graphically, to illustrate the role of aesthetics in mathematics, particularly through computer graphics, to demonstrate the beauty of creative thinking using computers, and to encourage computer usage for simulation and discovery.

The book is divided into 63 chapters, which average about five pages in length. Most of the chapters investigate topics that are curiosities or are otherwise of recreational interest.

The book is arranged into nine sections (Simulation, Exploration, Visualization, Speculation, Invention, Imagination, Fiction, Exercises for the Mind and Eye, and Computers in the Arts and Sciences). A majority of the nine sections represent things that researchers might do with a computer. Some examples will suffice. The "Simulation" section presents some simple simulations of various phenomena. The "Visualization" section illustrates the use of computer graphics in various fields or just for their own beauty. The "Speculation" section provides the results of Pickover asking various (often thought-provoking) questions of scientists, and so on. There are also several appendices that discuss further information on some of the topics in the book or suggest other problems of interest to investigate.

For the most part, this book has been written to be accessible to the general reader. Some of the fractals and other graphics require somewhat advanced mathematics to fully understand (although it doesn't require mathematical knowledge to appreciate the end result) and implementing the algorithms discussed in the book would of course require programming skills. Even without such knowledge, there is enough text (and pictures; there is probably one figure per page on the average as well as a nice-looking colour section) for the most part that the reader can still follow along, and if not a new topic is only a few pages away. For more advanced readers, there are many equations, pieces of pseudocode, and information on how to get more information on a topic.

This book is a very thought-provoking book. Not everyone may be interested in every chapter in the book (it would probably be a rare person who would be) but there is enough variety that everyone should find topics of interest to them. Even though the book is nearly 25 years old, it dates fairly well. Some of the graphics look, well, 90s-ish, but much of the material is still relevant today.

**Rating:** 9/10