Composer David Diamond recalls playing the Sonata for violin and piano with the composer in Copland's New York loft at the time of the work's composition. Diamond said, ''I advised him to use harmonies in the last movement.'' The Sonata is in the usual three movements, the last two to be played without pause. Following the premiere in 1944 for which Copland was the pianist, Virgil Thomson called the Sonata ''one of its author's most satisfying pieces. It has a quality at once of calm elevation and of buoyancy that is characteristic of Copland and irresistibly touching.'' - Vivian Perlis