I find it fascinating that many of the greatest composers of the 19 th century—composers such as Berlioz, Schumann, Chopin, Mendelssohn, Wagner, Brahms, Dvorák, and Tchaikovsky—knew one another, and in many cases had very friendly personal and musical relationships. Schumann, for example, wrote his piano quintet for his wife, Clara, a great piano virtuoso …and Clara played the first public performance of the piece.