'Beautiful Mind' Mathematician John Nash Died At 86, But His Contributions Are Lasting

The Nobel Prize laureate leaves a legacy.

Following a car crash in New Jersey on Saturday, "A Beautiful Mind" mathematician John Nash died at the age of 86 alongside his 82-year-old wife, Alicia, state police said. The accident occurred when their taxi spun out of control as the driver tried to pass another car and hit the guard rail. The couple was ejected from the car and pronounced dead at the scene.

Nash had lived a long and incredibly productive life, one that included huge contributions to mathematics and work highlighting the plight of mental illness, which he struggled with for decades. 

His life was the inspiration for the Academy Award-winning film "A Beautiful Mind," which starred Russell Crowe. The movie was based on Nash's biography of the same title by author Sylvia Nasar.

Game theory and Nash equilibrium

Game theory is the study of formulating a winning strategy in the game of life, particularly when your competitors' actions are unknown and the options look slim.

Though Nash did not invent game theory — mathematician John von Neumann largely established the field in the 20th century — he did further the study to include more complex situations that extended beyond a zero-sum, I-win-you-lose analysis

The result is Nash equilibrium, a situation where a player's fortunes depend on how others act, and everybody tries to do the best for themselves as possible. The Nash equilibrium allowed people to analyze situations of conflict and cooperation, thereby predicting how people would behave — a concept that had wide-ranging applications in politics and economics — and ultimately earned Nash a Nobel Prize in the latter.

Highlighting the complexity of mental illness

In the 1950s, Nash struggled with mental illness and was later diagnosed with schizophrenia. At some points, he believed himself to be of a different — often mythical — character. Nash endured painful electroshock therapy and went in and out of mental institutions for decades.

His brilliant mind, besieged for years by delusions and hallucinations, made a stunning recovery after he simply chose not to be sick anymore, according to Nash. As he wrote in 1996:

"I emerged from irrational thinking, ultimately, without medicine other than the natural hormonal changes of aging."

Nash is survived by his sons, John David Stier and John Charles Martin Nash, and a sister.