Mathematical Snapshots-Oxford University Press (1983)
In presenting this book to the reader, I should like to avoid the misunderstanding that any mathematician risks when he addresses himself to non-specialists. My purpose is neither to teach, in the usual sense of the word, nor to amuse the reader with some charades. One fine summer day it happened that I was asked this question: “You claim to be a mathematician; well, what does one do all day when one is a mathematician?” We were seated in a park, my questioner and I, and I tried to explain to him a few geometric problems, solved and unsolved, using a stick to draw on the gravel pathway a Jordan curve, or a Peano curve . .. That was how I conceived this book, in which the sketches, diagrams, and photographs provide a direct language and allow proofs to be avoided or at least reduced to a minimum.