The sciences of music analysis and music semiotics concern themselves chiefly with these replicable formulae. This is necessarily the case, since sciences are abstract and rational; they must deal with types, rules, generalities. Occasionally, a music analyst will suggest that she has somehow approached the question of musical uniqueness through ordinary analysis. Rudolf Réti, for example, believed that his theory of motivic relation might permit him to define greatness in music, since the most convincing examples of motivic unity were found in masterpieces. But motivic relations can also be found, alas, in the most insignificant pieces. Most methods of music analysis, even those enlightened by semiotics, persist in describing the general and the universal. Croce's "imagination", which devises the irreplicable and unique features of a musical work, appears to begin at the point where all general analytical features leave off.
In spite of this, there seems to be some kind of special uniqueness about the best music, even after one has traced its topical allusions and demonstrated its Schenkerian symmetries. Somehow or other, fine music achieves its effect exactly when it passes beyond analysis; when it uses generalizable features in idiosyncratic ways. This boundary -- between what can be analyzed, and what seemingly can't -- is itself usefully traced by some of the best analysts. For example, Daniel Chua reveals the greatness of some of Beethoven's late quartets by pressing traditional analyses on them, and watching his analyses "buckle" (his evocative word) (Chua: 1995). Semiotics has played its part in marching along this boundary, too; Tarasti's narrative analysis of Chopin's Polonaise fantaisie (Tarasti: 1994, 138-154) shows that the oddest and most unconventional of works can be illuminated by an analysis that avoids preconceptions.
There is a philosophical tradition, however, which suggests that all rational attempts to approach musical (and literary) uniqueness are misguided. Alongside the faculty of reason, which has to govern scientific endeavour, there is a faculty of individual perception, which permits us to discern what is different or particular about a phenomenon, and has its roots in primeval innocence. Giambattista Vico called it "imagination".
The studies of Metaphysics and Poetry are in natural opposition one to the other; for the former purges the mind of childish prejudice and the latter immerses and drowns it in the same; the former offers resistance to the judgment of the senses, while the latter makes this its chief rule; the former debilitates, the latter strengthens, imagination... hence the thoughts of the former must necessarily be abstract, while the concepts of the latter show best when most clothed with matter (Vico, Scienza nuova, quoted by Gilbert and Kuhn: 273).
Early man, in observing nature, imagined that each event was the work of some super-being, just as their lives were affected by contingent beings in their surroundings. Incapable of abstract ideas or reason, they attributed contingency and corporeality to all observations; their thought was governed by imagination, not logic. Benedetto Croce follows Vico in associating art with the freshness of man's original naiveté.
Imaginative in essence, it shares imaginationts primal innocence. As the most elementary kind of human language, it gives form to the passions, attractions, and revulsions of youth taking the world freshly. It articulates the formless flux of raw experience (Gilbert and Kuhn: 550).