I was sorry to hear this morning that John Nash and his wife Alicia died yesterday in a car crash (news story here). They were in a taxi on the New Jersey Turnpike, heading home from the airport after a trip to Norway where Nash was awarded the Abel Prize.
Nash’s mathematical career was cut short by the onset of mental illness, which he then struggled with for many years. Sylvia Nasar’s A Beautiful Mind is a wonderful biography, doing a great job of accurately portraying Nash’s life, including the role of the mathematics community in its various parts. The movie version is another story, especially in the way it shows Nash’s mathematical achievements as somehow being due to his delusions, when what really happened is that the onset of delusional thinking is what made it no longer possible for him to continue doing research at the highest level.
During the years I was a graduate student in Princeton, Nash was often to be seen, especially in the mathematics/physics library, and I talked to him a few times. The first time was when he stopped me one day, told me he had seen my name on the physics department picture board, and was curious about the origin of my last name. While I had heard stories about Nash, that he was mentally ill, spent his time writing delusional things on the hallway blackboards, he seemed fine to me. This was a period (early 1980s) when he had stopped writing on the blackboards and was successfully dealing with the illness. I was very glad to see how later on he was able to lead a more normal life and enjoy the recognition he deserved.
Update: The New York Times has an excellent long obituary of Nash this morning, presumably mostly prepared before his death.