One Two Three...Infinity: Facts and Speculations of Science by George Gamow (Dover, $13). I have aspired to write a book as influential to others as this book was to me. I read it in ninth grade ...

For example, one infinity—the one most people are familiar with—is an infinite set of natural numbers: 1, 2, 3, and so on. However, there’s also an infinite set of real numbers, which ...