From Wikipedia, the free encyclopedia: Franz Schubert‘s Symphony No. 8 in B minor (sometimes renumbered as Symphony No. 7, in accordance with the Neue Schubert-Ausgabe), commonly known as the”Unfinished Symphony” (German: Unvollendete), D.759, was started in 1822 but left with only two movements known to be complete, even though Schubert would live for another six years. A scherzo, nearly completed in piano score but with only two pages orchestrated, also survives. It has long been theorized that Schubert may have sketched a finale which instead became the big B minor entr’acte from his incidental music to Rosamunde, but all the evidence for this is circumstantial. One possible reason for Schubert’s leaving the symphony incomplete is the predominance of the same meter (three-in-a-bar). The first movement is in 3/4, the second in 3/8 and the third (an incomplete scherzo) also in 3/4. Three consecutive movements in basically the same meter rarely occur in symphonies, sonatas or chamber works of the great Viennese composers.Haydn’s Farewell Symphony has been cited as a notable exception; but its finale, though ending with a 3/4 Andante in which all the instruments drop out one by one leaving two duetting solo violinists ending the work in F-sharp major, starts with an orthodox sonata-allegro in the tonic F-sharp minor in common (i.e., duple) time transitioning after the recapitulation to the unorthodox extended slow 3/4 “Farewell” coda in modified sonata form.
Schubert’s Eighth is sometimes called the first Romantic symphony due to its emphasis on expressive melody, vivid harmony and creative combinations of orchestral tone color despite the architecturally imposing Classical sonata-form structures of its two completed movements highlighted by the dramatically climactic development section of the first movement based solely on its quietly sinister opening theme.
To this day, musicologists still disagree as to why Schubert failed to complete the symphony; or even whether he did fail to complete it. Some have speculated that he stopped working on it in the middle of the scherzo in the fall of 1822 because it was associated in his mind with the initial outbreak of syphilis, or simply that he was distracted by the inspiration for his Wanderer Fantasy for solo piano which occupied his time and energy immediately afterward; or perhaps a combination of both factors.