I never heard the name Barbara Cook until I was a senior in college. The girl I was dating told me about the woman who played the role of Cunegonde in her favorite musical, “Candide.” I’d never heard of that either, but in 1972 I saw the play in New York with that girlfriend, who had become my wife.

Ms. Cook was not in that revival, but I own the original cast recording and have listened to her lustrous soprano voice countless times. I heard Ms. Cook in concert when she was nearly 80, and the voice was still clear, resonant, and pure.

Barbara Cook died in July at the age of 89, singing nearly to the end. And when her voice, but not her heart, was stilled, her friends brought music to her bedside. John Pizzarelli strummed “The Way You Look Tonight,” Vanessa Williams sang “Send in the Clowns,” and others such as Josh Groban, Audra McDonald, and Kelli O’Hara, either serenaded her in person or sent recordings and messages of love.

When I read she had died, I thought back to when I first heard her name, and about the pleasures this woman has given me. We never met, but our lives intersected. She sang from her heart and touched mine.

You may not have had the “Barbara Cook” experience, but perhaps you have known something like it with Frank Sinatra, Judy Garland, the Beatles, or Elvis Presley. For my father, it would have been Al Jolson.

The young Leonard Bernstein wrote the music for “Candide,” and the great poet Richard Wilbur wrote the lyrics. Many years later, both of them came to Peterborough as MacDowell Day medalists.

Despite its creators, the play was not a success when it opened on Broadway in 1956. Today, however, it is one of our most enduring musicals. I don’t think it’s just because of the beautiful music. I think it is at least as much about the plot, taken from a novel originally written two hundred years earlier by the French writer Voltaire.

The story tells about a young man named Candide, whose tutor teaches him that this is “the best of all possible worlds.” Early in the musical he sings, “Life is happiness indeed” and “I love all my fellow creatures.” He falls in love with Cunegonde, but her guardian disapproves and banishes him out into the world. Candide laments, “Is it true? …Can the heart find strength to bear it?”

Candide travels to many countries and is shocked by what he sees, evil that “deals more coldly than I had dreams it would.” Still the idealist, he blames himself. “It must be me,” he laments.

Candide mistakenly believes Cunegonde has died. He is unaware of her unhappy downfall in Paris, “forced to bend my soul, to a sordid role” of degradation. In the knockout song “Glitter and Be Gay,” she decides not to be “basely tearful” but to show her noble self and be “bright and cheerful.”

Her optimism is ultimately rewarded. To their great surprise, the two lovers are reunited. Candide wonders, “How can this be so? You were dead you know.” She answers, with a woman’s pragmatism“That is very true, Ah, but love will find a way,” praises Candide for having survived so cleverly, and asks him where he has been. “To and fro,” he tells her, and “I would do it all again, to find you at last.”

The play offers a parable for our time. It tells us that life is “neither good nor bad.” And it concludes with the two lovers facing the challenge of the future. Candide proposes marriage. “Let us try, before we die, to make some sense of life.” He and Cunegonde sing the play’s last song together:

We’re neither pure, nor wise, nor good
We’ll do the best we know.
We’ll build our house and chop our wood
And make our garden grow…
And make our garden grow.