On Friday evening, in the Great Concert Hall of Hamburg's stunning new Elbphilharmonie, Presidents Donald Trump and Vladimir Putin, Chancellor Angela Merkel, Turkish President Recep Tayyip Erdogan and 16 other world leaders, along with 2,000 other invited guests, will take a break from speechmaking, grandstanding and diplomatic language - actually, from any spoken words at all - to listen to a famous work of music as American conductor Kent Nagano raises his baton to lead the Hamburg State Philharmonic Orchestra.

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Lasting roughly 70 minutes, Ludwig van Beethoven's Ninth Symphony, Opus 125 is a work about which much has been said and written. Back in 1901, French composer Claude Debussy noted, "The Ninth Symphony has been shrouded in a fog of noble words and decorative statements. It's the masterpiece about which more nonsense has been spread than any other. One can be amazed that it hasn't long since been buried under the mountain of writings issued forth by it."

One reason for that "mountain of writings" is that this symphony incorporates a vocalized text in the final movement.

"Of all the works in the mainstream repertory of Western music, the Ninth Symphony seems the most like a construction of mirrors, reflecting and refracting the values, hopes and fears of those who seek to understand and explain it," musicologist Nicholas Cook once observed. In 1999, Esteban Buch wrote a book titled "Beethoven's Ninth - A Political History" on the many uses and abuses, understandings and misunderstandings of the work.

Triumph for a deaf Beethoven

Backtrack to Vienna, May 7, 1824. After the world premiere of the symphony, a violinist in the orchestra by the name of Joseph Michael Böhm observed: "Beethoven conducted, wildly beating hands and feet as though he wanted to play all the instruments and sing the chorus all by himself. But we musicians had been instructed to follow Durpot, the actual conductor."

Oblivious to the fact that the work had ended, the deaf composer actually kept on conducting until one of the singers gently turned him around so that he could see the ovations.

The choral finale was a radical departure, but the work was a success. Yet some doubted not only Beethoven's hearing capacity but also his sanity. Years later, Italian opera composer Giuseppe Verdi was among the detractors, although his criticism focused on Beethoven's setting of the vocal lines.

"It will be an easy task to write as badly for voices as is done in the last movement," he wrote in 1878. Much more recently, the late conductor Gustav Leonhardt said, "That 'Ode to Joy,' talk about vulgarity! And the text! Completely puerile!"

Songmeanings.com: Ludwig Van Beethoven, Ninth Symphony, Opus 125

Everyone hears what he wants to hear

That choral finale made Beethoven's Ninth a projection surface for every kind of ideology. The poem on which it is based, Friedrich Schiller's "An die Freude" ("Ode to Joy"), had interested Beethoven since his youth. But when the chorus sang "All men shall become brothers" at the first performance, it must have rung hollow to some in the audience.

Like Beethoven, many of them had placed their hopes in the French Revolution in their youth and later in Napoleon Bonaparte, only to see the Frenchman plunge Europe into a devastating war, after which came the restoration of monarchies big and small. Beethoven even dedicated his Ninth Symphony to a king, Friedrich Wilhelm III of Prussia.

Yet it is a text which Karl Marx could describe as a "solemn mass of earthly joy" and Richard Wagner could hail as a "cry of the universal love of man." Wagner, in fact, took Beethoven's Ninth as the point of departure for his own work, and this was the only piece of music - other than his own - that had Wagner's blessing to be performed in his festival theater in Bayreuth.

The memorable piece of music is an integral part of 20th century history. Soviet leader Josef Stalin saw the Ninth as "the right music for the masses." To deliver optimism to other masses, Nazi propaganda minister Joseph Goebbels ordered it played effusively on the radio in the hopeless final months of World War II. The symphony had been performed ritually on Adolf Hitler's birthday, and prisoners at the concentration camp in Auschwitz were forced to sing the tune.

The apartheid regime in former Rhodesia (now Zimbabwe) made it the country's national anthem, and in 1988 demonstrators in Chile sang it at the ousting of dictator Augusto Pinochet.

A durable and flexible symphony

The myth and mystery of Beethoven's Ninth are such that the United Nations included the original score in the Memory of the World Register in 2001. In 1972, the European Council declared the hymn Europe's official anthem, and in 1985, it became the anthem of the European Union, expressing, even without the words, "the European values of freedom, peace and solidarity."

Did the makers of the 1990s video game Civilization II have these ideals in mind when they used the music in a less than symphonic setting? Perhaps not, but the uses of the symphony are myriad.

In the 1960s, the scherzo second movement was the theme of the NBC Nightly News in the United States, while parts of the symphony turn up in films including the Beatles' "Help!" of 1965, Stanley Kubrick's "A Clockwork Orange" of 1971 and the Bruce Willis action movie "Die Hard" of 1988. 

In the late 1980s, when a new technology - the compact disc - emerged, the companies Sony and Philips negotiated on format issues. Legend has it that they consulted Herbert von Karajan, then conductor of the Berlin Philharmonic, and that he advised that the new format should have a storage capacity adequate to contain a complete performance of Beethoven's Ninth. A recording of Karajan's predecessor Wilhelm Furtwängler was used as a reference, and the format thus set at 73 minutes.

In 1918, the German workers' movement began performing the work on New Year's Eve, a tradition that continued in the Nazi era - and after the war, in both East and West Germany. Today there are hundreds of performances on New Year's Eve in cities big and small - and not only in Germany. In Japan alone there are scores.

After the breach of the Berlin Wall in 1989, American conductor Leonard Bernstein hurried to Berlin to conduct a performance of Beethoven's Ninth at the Brandenburg Gate, changing one word in the final chorus to mark the milestone. In a gesture that offended purists but enthused the masses, instead of "Freude schöne Götterfunken" ("joy, divine sparks"), it was now "Freiheit schöne Götterfunken," replacing "joy" with "freedom."

And those words

"Be embraced millions, this kiss of the whole world" sounds unambiguous enough in a text setting that includes references to wine, nature, a loving God, celebration and joy. It's a text with religious overtones, heroism and bacchanalia and culminates in the declaration "all men shall become brothers."

Yet even here, the club of mankind excludes some: namely, those who choose not to join in: "Yea, if any hold in keeping / Only one heart all his own / Let him join us, or else weeping / Steal from out our midst, unknown." It is a moment of doubt amidst all the affirmation, and Beethoven sets this part of the text to a sudden reduction of volume in the sound texture.

Inclusive - and in a certain sense, exclusive - would seem to be the thrust of Beethoven's Ninth. Whether the message is picked up on, slept through or misunderstood by those in attendance at the Elbphilharmonie on Friday may be reflected in the results of the summit - or maybe not. Here, too, music is a law unto itself.