The etude is a Romantic idea. It appeared in the early nineteenth century as a new genre: a short piece in which the musical interest is derived almo… - Charles Rosen

The piano is the only keyboard instrument in which one can grandly vary the effects of the harmonics or overtones of a chord at will by balancing the sonority in different ways.

Mendelssohn was the greatest child prodigy the history of Western music has ever known. Not even Mozart or Chopin before the age of nineteen could equal the mastery that Mendelssohn already possessed when he was only sixteen. Most astonishing is the nature of Mendelssohn's precocious talent: not only a gift for lyrical melodic lines and delicate, transparent textures, but, above all, a control of large-scale structure unsurpassed by any composer of his generation.

Nevertheless, music will not acknowledge a context greater than itself—social, cultural, or biographical—to which it is conveniently subservient. To paraphrase Goethe's grandiose warning to the scientist: do not look behind the notes, they themselves are the doctrine.