A piano sonata approximately 40 minutes in length, which pursues an unprecedented way for the piano to resonate.

The inspiration for this sonata came in November 1988. In May of the same year, after presenting "Symphonic Ballad" at the 14th Min-On Contemporary Composers Festival, I was overcome by a sense of emptiness, rendering me unable to settle on even a single note. Amidst this, my grandfather, who had been like a father to me, passed away. While keeping an all-night vigil by candlelight, numerous piano melodies and sounds surged from within me, compelling me to resolve to compose this sonata. I spent over two years organizing the vast collection of sketches I had accumulated, completing the third and fourth movements in 1991 while the first and second movements remained unorganized. After being left untouched for 15 years, I undertook the revision and organization of the first and second movements starting in the winter of 2006. However, in the end, it was merely a process of consolidating the material while preserving the energy and sensibility of that time.

The work consists of four movements: The first movement progresses from the presentation of numerous themes and the conflict of various pianistic elements towards a scream. The second movement begins with a slow-movement-like theme but, after encountering the same wall as the first movement and becoming disordered, is purified with a sense of nostalgia. In the third movement, numerous themes introduced previously are revisited within a single climax, ultimately leading back to the opening motif of the first movement. This then leads to the final movement, a toccata that once again actively confronts intentions and overwhelms everything. The final movement reaches its peak with the melody sung at the end of the second movement, concluding thereafter with a solitary coda.

This sonata is one of the most important works supporting me today, being both lengthy and extremely challenging. After a long period of approximately 18 and a half years from its conception, it was premiered by Mamiko Tomari in April 2007, leading to the present recording. The performance seems to express an unparalleled unique pianism not found in existing piano works, and my own heartfelt "song".