Following the acquisition of an Erard fortepiano in 1803, Beethoven was inspired to write this sonata, one of the finest among his 32. The composer had known for about two years that he was losing his hearing, but he was far from complete deafness. The crisper tones of the new instrument were much more appealing to him than his old Walter piano. This sonata, dedicated to the composer’s patron and friend Count Ferdinand von Waldstein, came on the scene as a great challenge for pianists. The first movement, marked Allegro con brio, begins with a rhythmic, driving, obsessive theme that creates an enormous sonic space and a veritable energy field between the hammering chords in the left hand and the right hand’s completion of the phrase, several octaves higher. Reiterated, starting from a slightly lower register, the theme seems less energetic, but the effect is deceptive. While the energy level remains high, additional ideas are developed, and the second subject is introduced as each of these ideas strives to dominate the composition’s discourse. This second subject, in E major, introduces a moment of tranquillity, but calm quickly dissipates, moving toward a brilliant, triumphant finish with the underlying rhythmic intensity of the main theme. The development section begins with a darker cast to the main theme, which then goes off into a new direction. The previous materials become interlaced and developed, and this process generates considerable tension. In the reprise that follows, Beethoven ingeniously avoids a mere restatement by expanding on the phrase at the end of the main theme’s first reappearance.