Movement 1: Andante con moto – Allegro vivace
Movement 2: Andante con moto quasi allegretto
Movement 3: Minuetto: Grazioso
Movement 4: Allegro molto
Germane to the work as a whole is the chord of the diminished seventh (three minor thirds on top of each other). This is the most famously ambiguous chord in music — someone called it the Clapham Junction of music because you can go almost anywhere from it. It pervades the strange searching introduction, where it receives cryptically exhaustive treatment. Beethoven was dismissive of its too frequent use — by Weber, for instance — but here he explores in it mysteries undreamed of by any other composer. It gives way to the very bright C major Allegro — but in that, too, we find the diminished seventh has a role. Notice the successive entries of the instruments at the recapitulation, on successive notes of the chord. The development has at its heart a magnificent repudiation of this chromaticism, the first two notes of the movement transformed into a mighty song of mountain air. But far from dispelling the mystery, it heightens it.
The A minor second movement is unique in Beethoven, who wrote nothing else like it. Like the introduction to the Quartet, it has a fixation, but on themes as well as harmony. In rhythm it is also obsessive and there is a fateful fascination about it. The design is also unusual, a sonata form with reversed recapitulation, making a point of the polar opposition of the tritone A and E flat (the diminished seventh consists of two overlapping tritones!).
After this the C major Minuet is a period of repose, a soothing influence, switching on normal light. It is beautifully composed, concealing the skill of its smooth counterpoint. The Trio is more lively and homophonic, in the key of F.
A link leads straight into the tumultuous finale, beginning with the fieriest fugato Beethoven had yet conceived. Defiance and energy are shot through the music from start to finish, in what is to date the greatest of Beethoven's finales. If you listen acutely you will hear an anticipation of Egmont in it (the coda of the Overture).
from notes by Robert Simpson © 1991