Content
A large part of the book concerns Erdős, but a lot of it is about other mathematicians, past and present, including Ronald Graham, Carl Friedrich Gauss, Srinivasa Ramanujan, and G.H. Hardy. In the book, Erdős enjoys listening to Hardy when he speaks about Ramanujan. Hoffman also tries to give examples of what mathematics is and why he views it as important, and why many mathematicians such as Erdős devote their whole lives to mathematics. It also contains some history of Europe and the United States during Erdős's time.
The book overall portrays Erdős in a favorable light, pointing out his many endearing qualities, like his childlike simplicity, his generosity and altruistic nature, and his kindness and gentleness towards children. However, it also attempts to illustrate his helplessness in doing mundane tasks, the difficulties faced by those close to him because of his eccentricities, and his stubborn and frustrating behavior.
Erdős's nursing of Jon Folkman
Main article: Jon Folkman
Hoffman reports the following anecdote, which displays Erdős's single-minded devotion to his friends and mathematics. In the late 1960s, the young mathematician Jon Folkman was diagnosed as having advanced brain cancer. During Folkman's hospitalization, he was visited repeatedly by Ronald Graham and Paul Erdős. After his brain surgery, Folkman was despairing that he had lost his mathematical skills. As soon as Folkman received Graham and Erdős at the hospital, Erdős challenged Folkman with mathematical problems, helping to rebuild his confidence.
Hoffman notes that Folkman's recovery was short-lived. Notwithstanding his ability to solve the problems posed by Erdős, Folkman purchased a gun and killed himself. Folkman's supervisor at RAND, Delbert Ray Fulkerson, blamed himself for failing to notice suicidal behaviors in Folkman. Years later Fulkerson also killed himself.