My music must be an artistic reproduction of human speech in all its finest shades. That is, the sounds of human speech, as the external manifestations of thought and feeling must, without exaggeration or violence, become true, accurate music.

Letter to Lyudmila Shestakova, July 30, 1868; Jay Leyda and Sergei Bertensson The Musorgsky Reader (1947) p. 113.