The sonata is conceived on a symphonic scale, with a four movement structure that could be viewed from two different perspectives. On one hand, the narrative flows in one direction - we go from the light of the grand opening movement and the impish Scherzo into the deepest darkness of the slow third movement, gradually re-emerging from it in the connecting Largo, and fully triumphing in the final fugue, which is our goal and aim. On the other, the Hammerklavier's form shows an exquisitely measured symmetry of proportions - both outer movements are eleven to twelve minutes long; going inward from the edges, we find the Scherzo and Largo at three minutes each; finally, at the centre, we reach the slow movement - which, at closer examination, exhibits the same five-part symmetry itself! The heart of this central movement, and thus the heart of the sonata, is the passage at 23:30, one of Beethoven's most powerful personal musical utterances. Both views co-exist, supporting the vast musical tapestry, and helping unite the movements into one cohesive, albeit very complex, whole.
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