Bartók once said that a simple folk melody can accommodate more complicated harmony. And here is a case in point. This descending Dorian tune repeats itself while the text changes, but the piano accompaniment changes quite bit along with the text, from consonance at the beginning to something more dissonant. I learned a great deal from performing this song many years ago.
Twenty Hungarian Folksongs 1. Tomlocben (Jail) by Béla Bartók