He is among the most enduringly popular of classical composers, and his influence on subsequent Western art music is profound; Beethoven composed his own early works in the shadow of Mozart, and Joseph Haydn wrote that "posterity will not see such a talent again in 100 years. The necessity to keep composing was all the more tortuous because of his suffering. Bona nox ("Good night") K. Czech is the language spoken in the Czech Republic.