„The editor of this selection from Chopin’s Pianoforte Studies has, however, no such intention; on the contrary. he wishes to make some of them, which owing to their difficulty have hitherto remained unpopularised, more accessible, particularly to the amateur, by pointing out the way to their correct study. And thus, on the basis of the technical facility to be acquired through these pieces, to enable even the non-professional to enjoy a more intimate acquaintance with those works of the classical romanticist, which, though representing the best and most undying side of his genius, have found till now but a small, though daily increasing circle of admirers; for the “Ladies’-Chopin”, which for forty years has blossomed in the pale and sickly rays of dilettantism; the “talented, languishing, Polish youth” to whom the most modest place on the Parnassus of musical literature was denied by the amateurish criticism of German professors, is as little the genuine entire Chopin, as is the Beethoven of “Adelaide” and the “Moonlight Sonata”, the god of Symphony. Truly a span of time must yet elapse before the matured and manly Chopin, the author of the two Sonatas, the 3rd and 4th Scherzos, the 4th Ballade, the Polonaise in F# minor, the later Mazurkas and Nocturnes etc., will be completely and generally appreciated at his full worth. At the same time much may be done by preparing and clearing the way; and one of the best means towards this end is sifting the material, and replacing favourite and unimportant works, by those less known though more important.“
— Hans von Bülow
Preface to Instructive ausgabe. Kalvier-Etuden von Fr. Chopin, 1880.