Composer and conductor Leonard Bernstein, shown here conducting the New York Philharmonic orchestra in 1963, was a legend in American music. Letters to and from Bernstein have been compiled into The Leonard Bernstein Letters, a new book edited by Nigel Simeone. Express Newspapers/Getty Images hide caption

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Leonard Bernstein's Age of Anxiety symphony is as unconventional as its creator. Courtesy of Library of Congress hide caption

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Leonard Bernstein leads the London Symphony Orchestra. He called Stravinsky's famously savage Rite of Spring "extremely tuneful and dancy, rhythmically seductive, beguiling." Ian Showell/Getty Images hide caption

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