A composer who chose silence

In the years after World War II, the composer Karl Amadeus Hartmann was more famous for what he didn't do than for what he did. For 12 years, he had led his exterior life in Nazi Germany, but his interior life was elsewhere. He was an exemplar of what came to be called "inner emigration."

Since Hartmann's death in 1963, the reputation of his music has slowly but steadily grown, and several composers and prominent performers from later generations have advocated for it -- just as Hartmann worked tirelessly to promote the music of others.

Ingo Metzmacher, the Boston Symphony Orchestra's guest conductor this week, has been a prime mover in the current revival of interest in Hartmann. Back in the 1990s, Metzmacher became the first conductor to record the complete cycle; his set is still available on three EMI CDs. His BSO program is the American premiere of Hartmann's Fourth Symphony.

Hartmann, alone among composers who remained in Germany during World War II, escaped the taint of association with the Nazis. Paul Hindemith, Kurt Weill, and others had fled the country, so Hartmann could easily have seized the opportunity to advance his own position, but he chose not to. He played no role in the cultural politics of the time, and he silenced himself -- none of his music was performed in Germany. Other composers, such as Carl Orff and Richard Strauss, were more accommodating.

In practical terms, Hartmann was able to get away with this because his wife was well-to-do, so he didn't have to make his living from music; he was also still a young and relatively obscure figure (in 1933, when the Nazis came to power, he was only 28).

More importantly, Hartmann chose his path out of principle. "No artist," he wrote, "unless wishing himself to be written off to nihilism, can sidetrack his commitment to humanity."

During the Nazi years, Hartmann did continue to write music, a lot of it, including an antiwar opera, "Simplicius Simplicissimus," and various works he later revised into the first six of his symphonies. His works, like the far more public music of Shostakovich written in the same period, were a painful diary of life in a terrible time, underpinned by profound belief in humanity.

Some of Hartmann's music was deliberately provocative and could have gotten him into deep trouble if anyone had actually heard it. Even before 1933, he was using themes from Jewish music, jazz rhythms and harmonies, and political hymns and protest songs from other eras and countries.

When war came, Hartmann enclosed his manuscripts in a zinc casing and buried them in the mountains. In 1945, Hartmann saw the forcible death march of 20,000 Jewish prisoners out of Dachau. He composed his Second Piano Sonata, one of his most powerful works, as a musical witness to what he had seen.

After the war, Hartmann became a much-honored figure and played a prominent role in rebuilding the musical life of Munich. Boston-based pianist Veronica Jochum vividly remembers Hartmann because of his association with her father, conductor Eugen Jochum, who led the world premiere of the composer's Sixth Symphony. She recalls him as a dignified but warm-hearted figure who liked to drink and talk music until late in the night.

Among Hartmann's postwar achievements was the creation of the prestigious Musica Viva series of new-music concerts in Munich. They were designed to expose musicians and the public to all the developments they had missed because of ideology and war.

The composer did not use the series to advance his own music. In fact, his music wasn't played a lot anywhere. He was profoundly dissatisfied with his prewar works and refused permission to perform them. After the war he spent most of his compositional time revising the pieces he had written during the conflict. No one is entirely sure why he did this, although as he grew older, and his musical goals, and his techniques for reaching them, became more advanced, he naturally wanted to improve his own work. Also he may have found the music as it stood too painful to contemplate.

Behind and within Hartmann's music you can hear such diverse figures as Bach, Bruckner, Mahler, Schoenberg, Berg, and Webern. But the voice is Hartmann's own, harrowingly intense and predominantly tragic in expression.

The Fourth Symphony is one of Hartmann's revised works. It was originally written for soprano and strings in 1938. The first two movements were instrumental, and the third brought in the soprano, who was to sing a setting of a Chinese poem. In the revision the soprano and text disappear.

The 35-minute piece is in three progressively shorter movements -- half the symphony is the first slow movement, which begins with 22 measures of the first and second violins unfurling an endless, searching melody in unison. The second movement is fast, a scherzo, with strong and brutal elements alternating with more capricious ones. The last movement, about half the length of the first, is slow again, and finally comes to rest on a series of repeated unison pizzicatos on middle C.

The symphony was the dominant orchestral genre of the 19th century. In the 20th century not many major composers focused on it the way Beethoven, Schumann, Brahms, Bruckner, and Mahler did. Sibelius and Shostakovich are by common consent the dominant symphonists of the 20th century. That view is unlikely to change, but the Metzmacher recordings offer an argument for the lasting value of Hartmann's contribution. Jochum says, "At least up until now, Hartmann was the last symphonic composer, in the traditional sense."

Ingo Metzmacher conducts the Boston Symphony Orchestra in the Fourth Symphony by Karl Amadeus Hartmann and Mozart's "Gran Partita" Thursday-Saturday evenings in Symphony Hall. Tickets $27-$105. 617-266-1200, www.bso.org. Metzmacher will also participate in a discussion of Hartmann's work led by music historian Frankpeter Messmer at the Goethe Institute Tuesday at 6:30 p.m.