7,[1] in accordance with the revised Deutsch catalogue and the Neue Schubert-Ausgabe[2]), commonly known as the Unfinished Symphony (German: Unvollendete), is a musical composition that Schubert started in 1822 but left with only two movements—though he lived for another six years.

It has been theorized by some musicologists, including Brian Newbould, that Schubert may have sketched a finale that instead became the big B minor entr'acte from his incidental music to Rosamunde, but all evidence for this is circumstantial.

Furthermore, its orchestration is not solely tailored for functionality, but specific combinations of instrumental timbre that are prophetic of the later Romantic movement, with wide vertical spacing occurring for example at the beginning of the development.

Some have speculated that he stopped work in the middle of the scherzo in the fall of 1822 because he associated it with his initial outbreak of syphilis—or that he was distracted by the inspiration for his Wanderer Fantasy for solo piano, which occupied his time and energy immediately afterward.

He felt obliged to dedicate a symphony to them in return, and sent his friend Anselm Hüttenbrenner, a leading member of the Society, an orchestral score he had written in 1822 consisting of the two completed movements of the Unfinished plus at least the first two pages of the start of a scherzo.

[5] A fourth movement finale in the home key (B minor) would have been the norm for any symphony written at that time, but there is no direct evidence that Schubert ever started work on it.

The second subject begins with a celebrated lyrical melody in that key, stated first by the cellos and then by the violins (sometimes drolly sung to Sigmund Spaeth's words as "This is ... the sym-phoneee ... that Schubert wrote but never fin-ished") to a gentle syncopated accompaniment.

This is interrupted by a dramatic closing group alternating heavy tutti sforzandi interspersed with pauses and developmental variants of the G major melody, ending the exposition.

In these measures, Schubert holds a tonic B pedal in the second bassoon and first horn under the dominant F♯ chord, that evokes the end of the development in Beethoven's Eroica Symphony.

Unusually for sonata form, the development section begins with a quiet restatement of the opening melody in the subdominant (E minor), a tonality usually reserved for near the end of a sonata form movement somewhere in the recapitulation or coda, and rises to a prolonged climax in the same key, starting with a dramatic variant of the opening melody in prominent trombones over a full orchestra.

... And when, after this nostalgic cantilena in the minor, there followed the contrasting G major theme of the violoncellos, a charming song of almost Ländler-like intimacy, every heart rejoiced, as if, after a long separation, the composer himself were among us in person.

A few odd hints here and there of complaint or irritation are interwoven ... their effect is that of musical thunder clouds .... As if loath to leave his own gentle song, the composer puts off too long the end ....The tonal beauty ... is fascinating.

The pianist Frank Merrick won the "English Zone" of the competition; his scherzo and finale were later performed and recorded (on Columbia), but are long out of print.

More recently, British musicologists Gerald Abraham and Brian Newbould have also offered completions of the symphony (scherzo and finale) using Schubert's scherzo sketch and the extended B minor entr'acte from his incidental music to the play Rosamunde Schubert wrote a few months later, long suspected by some musicologists as originally intended as the Unfinished's finale.

Due to his unusual use of material from Schubert keyboard works in the finale, Safronov's completion has been subject to criticism varying from definitely positive[11] to ambivalent[10][12] and negative.

[citation needed] In January 2019, Chinese technology company Huawei used artificial intelligence to create hypothetical melodies for the third and fourth movements, based on which Lucas Cantor then arranged an orchestral score.

[15] Goetz Richter writes, for instance: "The completed movements are trivial and achieve ultimately a loose and inauthentic family resemblance to Schubert".