Movement 1: Allegro

D major, 4/4 time. An innocent anacrusis descends into the heart. The parallel thirds are warm, and the phrase ending (m. 4) is like a rolling, bell-like laughter. Following the 8-bar main theme, a cheerful, conversational 8-bar transition leads to the secondary theme in A major (from m. 17). The first bar begins in a canonic style, then transitions into brilliant, piano concerto-like passages. At the end of the transition (from m. 37), a masterfully devised variation of the main theme, shadowed in A minor and intertwined with the secondary theme, appears, captivating the audience. The development section (from m. 50) begins in A major and unfolds virtuosic passages with dizzying modulations. In the recapitulation (from m. 73), the main theme is shortened, leading directly into the secondary theme without a transition; however, the seemingly omitted transition unexpectedly reappears after a concerto-like passage (from m. 95). Even in a recapitulation close to the standard form, a clever device is employed.