The story of John Nash's life — brilliant mathematician, troubled schizophrenic, and finally winner of the Nobel Prize in Economics — might have had a far harsher arc if not for his wife, Alicia Larde. Sylvia Nasar, the author of the book A Beautiful Mind, believes that Nash's choice of Larde revealed that his intelligence extended beyond mathematics. "It was Nash's genius," she writes, "to choose a woman who would prove so essential to his survival."

Alicia entered Nash's life as a young M.I.T. student dazzled by a star professor. Alicia remembers the first time she saw Nash. "I walked into the classroom, and I thought he was very nice looking," she said, "he was like the fair-haired boy of the math department." He, while the less eager partner, noticed her as well. "She," John admitted later in life, "was one of the few girls that attracted my attention."

Alicia was strikingly beautiful, well groomed and feminine, wearing full skirts and very high heels. She was intellectually sharp, cosmopolitan, witty, and socially savvy. According to author Sylvia Nash, Joyce Davis, a classmate of Alicia's, described the collegiate Alicia as "an El Salvadoran princess with a sense of noblesse oblige."

Alicia's extended family was an aristocratic clan that hobnobbed with the intelligentsia of El Salvador rather than with the country's landed oligarchy. Alicia's family spoke French and English as well as Spanish, traveled abroad, and lived well in a beautiful villa near the center of San Salvador, El Salvador's capital.

That life vanished when Alicia's father, a doctor, left for the United States in 1944. The family followed, first settling in Biloxi, Mississippi, and then in metropolitan New York City. With a reference written by the El Salvadoran ambassador to the United States, Alicia gained entry to the Marymount School, an exclusive Catholic girls school on the Upper East Side. Alicia's father, excited by his daughter's childhood dream of becoming the next Marie Curie, wrote a letter to the schoolmaster, asking her to help Alicia realize her aspiration to become a nuclear scientist. Alicia did well, becoming one of only 16 women entering the M.I.T. class of 1955.

John and Alicia met in an Advanced Calculus for Engineers class, but became a couple after Nash encountered Alicia at the university's music library, where she worked. Nasar points out that the two shared far more than an attraction: they were both close to their mothers; grew up in houses where intellectual achievement and status were supreme; and were both outsiders. These attractions pulled the two together in marriage in 1957.

After John's sudden onset of schizophrenia, Alicia tried to hide what was going on from friends and faculty. "Alicia wanted to save his career and preserve his intellect," recalled a friend. "It was her interest to keep Nash intact." That was her intention when, pregnant, she had her husband involuntarily committed to McLean Hospital outside Boston, something that Nash bitterly resented.

"I tried to remain positive as much as I could," Alicia remembers. " And I really tried not to feel pity for myself."

After three years of familial turmoil, Alicia filed for divorce, something that the Hollywod version of Nash's life left out. With the help of her mother, Alicia raised their son John on her own. Later he, too, turned out to have schizophrenia. In 1970 a decade after the divorce and with her ex-husband struggling just to survive, Alicia took him into her home not as a husband but as what she called her "boarder."

"They say that a lot of people are left on the back wards of mental institutions," says Alicia, speaking of her decision to take Nash in. "And somehow their few chances to get out go by and they just end up there. So, that was one of the reasons I said, 'Well, I can put you up.' "

"If she hadn't taken him in, he would have wound up on the streets," believes Nasar. "He had no income. He had no home. I think that Alicia saved his life." In the 1980s, John slowly emerged from schizophrenia and in 1994 he received a Nobel Prize in Economics for the game theory work he completed as a young man. In the spring of 2001, Alicia and John were remarried, 38 years after their divorce.

"We thought it would be a good idea," Alicia stated quite simply. "After all, we've been together most of our lives."