Leonard Bernstein would have turned 100 this August. As many centenary reflections have shown, it is hard to tell the story of this Great American Conductor-Composer without lapsing into the heroic style, turning his outsized personality into the key for unlocking his music.

Certainly the narrative sweep of his career is irresistible—the transformation of this son of Ukrainian Jewish beauty supply wholesalers into the darling of classical music, the last superstar in a musical culture that was turning from Beethoven to the Beatles. Bernstein held on to that audience; he commanded its attention. Even when he was not conducting he was a performer, the impresario for his own achievements. Already in 1939, when he submitted his senior honors thesis at Harvard, his examiner wrote, “I thoroughly disapprove of Mr. Bernstein’s arrogant attitude and of the air of superiority assumed by him.” This sense of self-assurance could be off-putting, but it was also part of his charm.

It is hard to tell the story of this Great American Conductor-Composer without lapsing into the heroic style, turning his outsized personality into the key for unlocking his music.

Whenever Bernstein appeared on public television, my father would pause from his work and issue a playful cry—“Lenny boy!”—and then sit down to listen. Like Bernstein, my father was from a poor family of immigrants. A wunderkind, he went on to be a biochemist, a pioneer in plant genetics. For him Bernstein was an obvious symbol for what a child from his world could accomplish. But I also detected an irony in that cry. My father, I think, could never quite get over the sense that Bernstein was too much of a ham, took himself too seriously, when after all he was just a schnook, a yid. His recordings, however, were abundant in our family’s collection, and they proved to be a source of consolation when our family suffered a terrible loss.

Neither of my parents had the benefits of a musical education. But as children we were all trained in the Suzuki method, one kid after another trying to be the next Jascha Heifetz. Both of my sisters were wonderful—far better than me—and all through my childhood I could hear them practicing. Sometimes at night I would go to sleep listening to Nancy in her room next door as she worked her way through a Bach partita, its phrases accompanying my dreams. I am not afraid to say my father felt a special fondness for Nancy as the child who most resembled him: quiet, patient, studious. Born with minor disabilities, she spent long stretches of the day in bed, with two piles of books—on one side were the books she had finished, on the other side the ones she intended to read. Nearly every week she would return large stacks to the library, and check out more.

Even when Bernstein was not conducting he was a performer, the impresario for his own achievements.

And then, when I was in high school, my sister died. To be more precise: she committed suicide. Even today it is not something I mention easily. Nancy was nineteen, endowed with the same uncanny intelligence as my father, on a full scholarship at Stanford and already pursuing scientific research. Her death was inexplicable, and it nearly destroyed my parents. Especially in the first year they were consumed by grief. My mother switched on lights, as if the darkness could be extinguished. My father grew silent, withdrawn. I can still recall his blank, devastated face.

All through that year, I was still trying to be a teenager, but my efforts were feeble. The concerns of my friends made little sense to me, and I retreated, nearly dropping out of school. I immersed myself in music, the only thing that still held meaning. After a brief rebellious phase with the guitar, I switched to the piano and stuck to it. I sought out a private teacher in composition, a joyful, brilliant, young man with a mellifluous Armenian name and an erudition that seemed boundless. Seated at the piano by his side I tried to learn what I could of music theory, plotting Bach chorales, learning to compose little fugues. The math was often beyond me: the voices would get tangled, forbidden parallel fifths kept sneaking in. I was not terribly good at it, but it was a private joy, and I started to imagine myself as a composer in Bernstein’s image.

In 1943, when he was only twenty five, Bernstein was asked at the last minute to fill in for the ailing Bruno Walter as conductor for the New York Philharmonic at Carnegie Hall. It was hailed not only as a debut but as an apotheosis, the arrival of a genius. In 1945 he was appointed music director of the New York City Symphony Orchestra, and in 1957, he completed his singular masterpiece, West Side Story. Written in collaboration with the lyricist Stephen Sondheim and the choreographer Jerome Robbins, it is a mixed-genre work of musical theater that stands out like the Statue of Liberty—a love song to the American dream and the one work by Bernstein that everyone knows even if they say they have never heard of Bernstein.

My father could never quite get over the sense that Bernstein took himself too seriously, when after all he was just a schnook, a yid.

The plot of the star-crossed lovers is lifted from Shakespeare, though in early drafts Robbins had reimagined the tragedy as a contest of ethnicities: Juliet as Jewish, Romeo as an Italian Catholic. In its finished version, however, the feud between the Montagues and the Capulets was transposed into a racially charged battle between two urban gangs, the Anglo Jets and the Puerto Rican Sharks. Bernstein’s score was a feat of genius; like many Americans of my generation, I can still sing it by heart. “Mar-i-a . . . ,” with its rising tritone that resolves into a fifth, was the shape of hope, especially for an adolescent desperate to fall in love. My own childhood had been ripped from me, but I took comfort in the tune. Later in my career when I lived briefly in New York, the new subway cars would sing out those same three notes, a rising seventh, resolving down a half step: “There’s a . . . place for us . . .  a time and place for us . . . ”

In 1958, fresh from that success, Bernstein became music director of the Philharmonic, where he remained until 1969, always testing convention and eager to introduce new music to the staid repertoire. His Young People’s Concerts were broadcast by CBS with lectures on topics from “What is a Melody?” and “What is Sonata Form?” to “Who is Gustav Mahler?”—efforts that enhanced his star value but also earned him the stigma of the middlebrow.

The reputation was not wholly unfair. With his centenary, Bernstein’s legacy as a composer is again the subject not only for praise but also for criticism. Performances such as Mass, the cosmic, genre-mixing spectacle from 1971, have been panned as an overblown mess; today it seems as fashionable as a leisure suit worn with sandals and beads. If I had been honest with myself as a teenager, I might have admitted that Bernstein’s contributions to “serious” music also didn’t speak to me. His symphonic works, such as Jeremiah (1942) and Kaddish (1963), seemed overpacked, laborious. And if there was a blind spot in his broad vision, it was the austere wing of musical modernism represented by the Second Viennese School. Along with Berg’s Violin Concerto and works by Aaron Copland, he conducted and recorded pieces by Elliott Carter, Milton Babbitt, Luciano Berio, and Roger Sessions. But he remained more or less faithful to tonality, and he could never fully overcome his sense that serial composers in Schoenberg’s camp had violated music’s eternal laws. It was a prejudice, perhaps, but it’s one that is still common.

Bernstein was an avatar of global consciousness, a man who embraced everything and obeyed few conventions.

Still, as I nourished fantasies about becoming a composer, it was the exuberant spirit from Bernstein that spoke to my own eclecticism. He excelled in mixed idioms of ballet and musical theater, in works such as Fancy Free (1944) and Candide (1956). And other performances, such as Serenade, a 1954 work for solo violin, string orchestra, harp, and percussion inspired by Plato’s Symposium, deserve to be heard again. (The Boston Symphony Orchestra performed the piece this September.) The violin’s opening phrases have an expansive tonality and lyricism that affirm the composer’s bond with Mahler: its first few bars are about as close as you can get to the first bars of the Adagio from Mahler’s fragmentary Tenth Symphony without inviting the charge of plagiarism. Then there is Chichester Psalms, the 1965 choral work for countertenor (or boy treble) and orchestra that Bernstein composed in 1965. Boisterous, almost hyperactive in its pacing, it is a headlong rush into sacred spheres. The biblical text is sung in Hebrew (“Make a joyful noise unto the Lord all ye lands”) but has an ecumenical feel that made it a favorite in Anglican services. In 1973 it was even performed at the Vatican before Pope Paul VI, who expressed gratitude to the composer: “Behold,” he said, “an American who has come to give music lessons to us of the old Europe.”

Bernstein was an avatar of global consciousness, a man who embraced everything and obeyed few conventions. At the time I knew nothing about his homosexuality, and I would hardly have cared; I had already grasped the crucial lesson that music is not a transcript of the soul. Untethered from identity, it speaks to all identities, bursting the boundaries of nation and tribe. Even today Bernstein is disliked by purists. In mid-twentieth-century America and long before multiculturalism had become the norm, he was the apostle of pastiche, an artist who took the greatest joy in crossing borders—between high and low, between sacred and profane, between romanticism and kitsch. He was music’s public intellectual, putting his charisma to work and serving as an evangelist to the masses, not only for music but for political causes, for peace and human rights.

By the end of high school, I spent long afternoons at the piano in my sister’s old room, the only place in my parent’s house where the piano would fit. For hours I would practice or improvise, inventing moody chords and melodies that had me half convinced that someday I might become a serious composer. Sometimes for no reason I would collapse into tears, not so much from trauma as from anger that my big sister had left me alone to cope with her death. I was caught by a paradox: Why didn’t she stay at least to help me with this pain?

I listened to a recording of Mahler’s Second Symphony, the “Resurrection,” again and again, not really grasping its religious language but sensing that the music might be a balm for my pain.

In spare moments between homework and applications for college, I tried to educate myself in music history, and I discovered the text of Bernstein’s The Unanswered Question (1976), originally his Norton Lectures at Harvard. Bernstein was a gifted teacher, his enthusiasm igniting my own. He explained how Debussy had stretched tonality, but why tonality could only be stretched so far before it broke and the human ear rebelled. At the time I did not fully realize that Bernstein was making a conservative’s argument, a defense of tradition. Mahler remained for him the summit of the canon, and he worked tirelessly to elevate Mahler to his rightful place in the concert-hall repertoire. I listened to a recording of Mahler’s Second Symphony, the “Resurrection,” again and again, not really grasping its religious language but sensing that the music might be a balm for my pain.

By the early eighties, Bernstein was an old man—still handsome, but with a visible paunch. Those massive ears and that nose were not quite congruent with the black tuxedo he wore for televised performances. I remember watching a broadcast of the Beethoven symphonies with the Vienna Philharmonic on public television. Bernstein was stuffed into his tuxedo—it looked uncomfortable—and the camera showed his face in close-up, the sweat and the ardor in every gesture. In the slow movement of the Seventh he grew ecstatic. It was his signature emotion, his trademark as a conductor. My father, still torn by grief, wandered into the room to see who was on the television, and called out happily, “Lenny boy!”