It would seem that the only thing more complicated than reading a book on mathematics would be listening to a book on mathematics. Reader Gilbert, however, has made Cheng’s surprisingly accessible book on category theory not only understandable but entertaining. Cheng uses everyday examples (recipes, LEGOs) to explain the logic behind the theories. Gilbert, whose voice is clear, bright, and enthusiastic, makes the whole thing fun. Each chapter begins with a recipe intended to illustrate a mathematical point. Although audio isn’t the best medium for cookbooks or equations, neither one distracts from the explanations of the theories. Solving problems, according to Cheng, is like doing calisthenics in the gym. Both are intended to work muscles (mental and physical) that will be useful when faced with real-life situations. Math, in the hands of this talented teacher and writer, becomes intriguing and welcoming rather than forbidding and overwhelming. The theories become increasingly complex as the book goes on, but the foundations make it understandable. This might be a tough sell for listeners who’ve struggled through high-school algebra classes, but anyone who gives it a chance will be rewarded by Cheng’s insights and Gilbert’s top performance. Booklist