“Shifting Echoes” is the title of this thesis. This title not only expresses the connections among the three selected works, but also symbolizes their responses to the past and their inspirations for the future within an ever-changing musical language. Spanning the Baroque, Classical, and Romantic periods, these works differ in style yet form a kind of resonance and transformation in their structures, emotions, and musical narratives—as if time and musical language intertwine, refract, and ripple into layers of echo.

Among these three works, Johann Sebastian Bach’s (1685–1750) "Italian Concerto in F Major" is the earliest voice. His composition represents the pinnacle of Baroque keyboard music, fusing polyphonic texture with the characteristics of the concerto style. The works of Beethoven and Schumann may be regarded as echoes and recreations of Bach’s legacy. Ludwig van Beethoven’s (1770–1827) Piano Sonata No. 18 in E-flat Major, “The Hunt,” Op. 31, No. 3, though belonging to the Classical period, demonstrates a multilayered structure reminiscent of Bach through its conversational thematic development, motivic transformations, and interplay of humor and lyricism. His music moves fluidly between order and freedom, inheriting Bach’s rigor while pushing it toward a more dramatic expression.

Robert Schumann’s (1810–1856) "Piano Sonata No. 2 in G Minor, Op. 22" further develops this multilayered structure. Through extreme contrasts, poetic language, and imaginative transformations, he merges Bach’s contrapuntal thinking with Beethoven’s structural logic to create a personal musical language characteristic of the Romantic era. Deeply influenced by Bach, Schumann frequently incorporates fugue, imitation, and motivic development into his piano works, giving his music an “echo-like” quality—responding to the musical heritage of his predecessors while also propelling music in new directions.

Although these three pieces share certain compositional legacies—such as approaches to modulation and harmonic progression—their use of musical language differs, revealing how musical style continually transforms and evolves throughout history. "Bach’s Italian Concerto in F Major, BWV 971" employs a precise and balanced musical language. His melodic lines are clear, his contrapuntal technique meticulous, and he shapes a concerto-like sense of layering through contrasts in dynamics. This is a music of rationality and order, built upon strict harmony and structure. Beethoven’s "Piano Sonata No. 18" adds dramatic variety to this sense of order. While his themes remain clear, they are more expressive and humorous, often taking unexpected turns that heighten the music’s expressivity. Schumann’s "Piano Sonata No. 2" fully enters the Romantic realm of personal musical language. His music is unpredictable—shifting in an instant from intensity to lyricism, or from dreamlike delicacy to fervent motivic development. His music resembles continuously transforming echoes: at times resonating with profound poetic depth, at other times bursting with unrestrained emotion and virtuosic energy.

“Shifting Echoes” also reflects the listening experience these works evoke. Bach’s lucid counterpoint, Beethoven’s rhythmic vitality, and Schumann’s dreamlike colors create ever-changing resonances on both structural and emotional levels. Whether performing or listening, one seems to perceive a dialogue across eras—a journey from rational architecture to emotional fluidity, ultimately merging into a deeply personal inner resonance.