Symphony No. 40 in G minor, KV. 550 was written by Wolfgang Amadeus Mozart in 1788. The two are the only extant minor key symphonies Mozart wrote. Nikolaus Harnoncourt conjectured that Mozart composed the three symphonies as a unified work, pointing, among other things, to the fact that the Symphony No. 40, as the middle work, has no introduction (unlike No. 39) and does not have a finale of the scale of No. 41's.
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