There is a revealing sardonic comment by Leopold Godowsky on a well-known statement of Paderewski, who once boasted, "When I don't practice for one d… - Charles Rosen

The relation of tonic to dominant is the foundation of Western triadic tonality. The attempt of the early nineteenth century to substitute third or mediant relationships for the classical dominant amounted to a frontal attack on the principles of tonality, and it eventually contributed to the ruin of triadic tonality. This ruin was accomplished from within the system, however, as mediant relationships were essential to tonality as conceived in the eighteenth century.

It is not, however, the unfamiliarity or strangeness of a work or of a composer's manner that is a bar to understanding, but rather the disappearance of the familiar, the ongoing disappointment of the expectations and hopes fostered by the musical tradition in which we have grown up.

The mazurka provided him with a repertoire of motifs, rhythms, and sonorities outside the main Italian, French, and German traditions of European music: he used it to create a series of works within this tradition which are absolutely personal—marginal works which challenge the center.
They are the most eccentric and original of Chopin's works. We shall never know exactly what and how much Chopin took directly from the popular folk tradition and how much he invented, but it does not matter: his originality is revealed as much in what he selected as in what he imagined. The folk dances gave him the possibility of exploring new harmonies, of exploiting the emotional effect of obsessive repetition, and of developing a new form of rubato.