Some composers have the rare gift of naivety. They don’t impress or stir us with complexity. They simply place a luminous chord here, a sad drooping phrase there, balanced with unerring rightness.

Most modern music exists outside the tonal system, and yet when I play music by the contemporary composers Kaija Saariaho or Tyshawn Sorey, the task is the same as it is with Beethoven or Schumann: to ...