Conceptual Art, 1834?

Though I didn't think of it at the time, encountering these odd neumes (silences? or long tones of unmeasured duration?) in Robert Schumann's Carnaval marked my introduction to conceptual music. All of Carnaval is a puzzle: a pianist could spend hours reading the score for its story, trying to figure out the secret code of musical motifs, the who's who in each piece, the extra-musical program buried in the thicket of notes and counterpoint. Schumann offers more than technical finger-busting in this concert piece; here, the music begins to involve other theatrical elements and refer beyond itself. With Carnaval, as with many of Schumann's other miniatures-linked-in-a-large-form compositions, the extra-musical elements do not alter one's ability to enjoy the music as pure music. I like that Schumann walks that fine line, joining an aspect of concrete purity with imaginative, conceptual fancy without eschewing one for the other. Is it not remarkable that this predates the Dadists, John Cage, et al?