The Man Who Loved Only Numbers

Some people are so outside the realm of normality that they almost seem to be a different type of human.  Their lives can make for fascinating biographies. Paul Erdös was just such a person.  Born in Hungary in 1913, he soon took to numbers.  At age 3 he would calculate how many seconds his parents' friends had lived.  Paul Hoffman's The Man Who Loved Only Numbers chronicles the bizarre life of Erdös.

Considered to be the most prolific mathematician in history, Erdös co-authored nearly 1500 scientific papers.  During most of his adult life, he traveled from university to university, or conference to conference, living out of two suitcases.  He never owned other possessions, did not have a home, and gave away money he didn't need.  Often, he would simply show up on a colleague's doorstep unannounced, spending a few days or weeks solving research problems before moving on to another city.  

Hoffman's interviews in the math world uncovered some great stories.  Later in his life, Erdös apparently needed an operation to correct his dimming vision, but delayed surgery because he was reluctant to lose precious work time.  He finally agreed to the procedure only when he mistakenly believed that he would be able to work during surgery.

In honor of his work and life, mathematicians humorously developed the Erdös number.  Erdös himself was awarded the number 0.  Erdös co-authors are awarded the number 1.  Co-authors of co-authors, the number 2.  And so on.  A low Erdös number is considered to be a great distinction (Steven Hawking, Bill Gates, Noam Chomsky and J. Robert Oppenheimer are 4's; Einstein a 2).  Hank Aaron jokingly has a 1 after co-signing a baseball with Erdös.  And, of course, a few mathematicians have tried to auction their Erdös numbers on Ebay.