Die Kunst einer Fuge is dedicated in its entirety to Theodor W. Adorno. Although Zacher, in a personal correspondence, indicates that he was particularly fascinated by Adorno's Einleitung in die Musiksoziologie ['Introduction to the Sociology of Music'], I will mainly refer to a different volume of collected essays.
 Adorno's volume, Prismen [Prisms], which includes the essay, 'Bach gegen seine Liebhaber verteidigt' ['Bach Defended Against His Devotees'], was first published in 1955. It reacts against an image of Bach that musicologists had built during the 1950's, namely that of a brilliant, but traditional (anachronistic, restorative) composer of church music. 'In him, it is said, there is once again the revelation - in the middle of the Century of Enlightenment - of the time-honoured bounds of tradition, of the spirit of medieval polyphony, of the theologically vaulted cosmos' (Adorno, 1981, p.135). Caught up by an inappropriate nostalgia for the church composer, music historians have turned him into a neutral, innocuous cultural monument. Adorno presents a totally different Bach. For him, Bach is a composer whose music rebelled against the church and broke through the narrow confines of the theological horizon. Rather than traditional, his music may be called modern, full of chromaticism and dissonances, mind-broadening compositional inventions, and new musical techniques (for example, the well-tempered system, a model of rationalization and subjective control in the Enlightenment). It is already announcing the change to the harmonic-functional music of the Viennese classics, Haydn, Mozart, and Beethoven. His music reflects 'the emancipation of the subject to objectivity in a coherent whole of which subjectivity itself was the origin' (Adorno, 1981, p.142). For Adorno, the advancement of history is marked by the subject that liberates itself from every objective order. He looks at Arnold Schönberg's free atonal music as a (temporary) end point. Bach is at the onset of these developments; as such, his shadow (his specter?) is cast before him.
 According to Adorno, the image of Bach as a reactionary and conservative composer has its parallel in certain ideas on the interpretive praxis (of Bach's works) that prevailed during the greater part of the 20th century. Every performance should be as authentic as possible; interpreters should faithfully approach the composition as it must have sounded in Bach's day. Differentiation is puritanically suspect. Subjective and anachronistic interventions must be avoided. 'At times one can hardly avoid the suspicion that the sole concern of today's Bach devotees is to see that no inauthentic dynamics, modifications of tempo, oversized choirs and orchestras creep in; they seem to wait with potential fury lest any more humane impulse become audible in the rendition' (Adorno, 1981, p.142-3). This all takes place under the guise of 'objectivity'. Adorno believes the fallacy of these purists (in Einleitung in die Musiksoziologiee he calls them Ressentiment-Hörer, 'resentment listeners') is that they equate objectivity with the historic first rendition. Adorno's first objection to this is that Bach was fairly flexible towards varying performances of his works. Like other composers of his time, Bach in large measure abandoned sound to taste, to subjective impulses. His second objection is that it is not at all clear whether a first performance or (an attempt at) a reconstruction of it would do justice to the intrinsic substance of his music. Adorno suggests that as Bach left the choice of instruments for his most mature instrumental works open (The Musical Offering and The Art of Fugue), he may have done so because he sensed a contradiction between his musical ideas and the sounds that were available in his time. Perhaps, Bach waited for sounds that would fit them.
 Adorno continues to speak about the relationships between the work, the score and the interpretation of the music. Music defines itself through the tension between the essense of the composition (the work) and its sensuous appearance (the interpretation). The object of interpretation is precisely this: to identify a work with its sensuous appearance. Yet, this can only be done by means of subjective labor and reflection. (Is the meaning of a text inherently implicit or concealed within the text itself, or is it the act of reading that produces meaning?) On this account, the demand for objectivity made by music historians becomes impossible. 'Objectivity is not left over after the subject is subtracted' (Adorno, 1981, p.144). So much for the relationship between work and interpretation. But Adorno immediately brings in a third component, the score: 'The musical score is never identical with the work; devotion to the text means the constant effort to grasp that which it hides' (Adorno, 1981, p.144). 'The intrinsic essence of Bach's music' (Adorno's words) is not equal to the score. It is concealed in the score and can only be recognized through intensive study of the score.
According to Rose Subotnik, these thoughts strongly evoke the deconstructive formulation of a text that is 'not identical with itself' (cf. Subotnik, p.226). Subotnik refers to a passage in Derrida's text, 'Différance', in which Derrida states that a 'signified concept is never present in and of itself, in a sufficient presence that would refer only to itself' (Margins, p.11. cf. Subotnik, p.233). Derrida comes to this conclusion after further elaboration on De Saussure's explorations of the differential character of the sign. The identity of the sign depends upon its differing from other signs; it depends on a network of oppositions through which each sign is distinguished and related to other signs. In this sense, a sign derives its meaning from what it is not; its meaning is never present within itself. Unlike Subotnik, I believe that this is something other than what Adorno tries to say. He is far removed from the idea that a note adopts meaning in relation to other notes. The passage appears more to reveal a kind of hermeneutics, a plea to track down latent and obscured meanings ('the effort to grasp that which it hides'). Deconstruction is expressly not after meanings that lay concealed behind or deeply within the text; rather, it directs its attention to what lies on the surface of the text itself (its materiality).
Can Adorno's work be related to deconstruction? It will be very difficult, if not impossible, to reconcile Adorno's insistent attention to 'the composition's essence' and the problamizing of fixed centers and essences in deconstruction. A deconstructive reading of Adorno's statement, 'the musical score is never identical with the work', seems only possible when we overlook what Adorno means by 'the work': the intrinsic essence of music. What then - i.e., when we overlook - could 'never identical' imply? First, a deficit of the score: a score never succeeds in fully expressing what it wants to present. It is precisely the score itself that disallows an immediate presence. This can still be in agreeance with Adorno's ideas. Second, a surplus: a score cannot be reduced to an original presence or intention. (Zacher's readings of Bach occupy the space between Bach's intentions and the score, between what Bach commands and cannot command in (his) musical language.) What is written bears a certain autonomy beyond the author; it is not dependent on his intentions. A score always means more: the opportunity to come to an exhaustive and closed formalization, valuation or meaning must be ruled out. Here, we seem to abandon Adorno's advocated meaning of the phrase. Third, the question could be asked as to what exactly 'the work' is. What is 'the intrinsic essence of music'? Is there one single essence? Is the essence immutable or is it historically evolving? Can we ever grasp it since the only way to eventually grasp it is precisely through a score or through everchanging performances? Can it only be grasped through that which it conceals (the score as precondition for the work)? Can the essence even be the différance - that which makes possible the presentation of the being-present, without ever being presented as such, that which is never offered to the present (cf. Margins, p.6)? Or am I bringing Adorno into a context here in which perhaps he feels ill at ease? How deconstruction is at work in the philosophy of Adorno needs further elaboration.
 Adorno regards true interpretation as an x-ray of the work. 'Its task is to illuminate in the sensuous phenomenon the totality of all characteristics and interrelations which have been recognized through intensive study of the score' (Adorno, 1981, p.144). The claim puts a great deal (perhaps an impractible amount of pressure) on the interpreter or performer. To demand that the totality of all characteristics and interrelations be heard is, at best, to ask for an ideal situation. Is it possible to determine the boundary of this totality? Will not every interpretation, every specific reading of a text, every 'Entbergung' unavoidably leave much unaddressed, concealed? Every interpretation adds new meaning to the text. This seems an infinite process. By playing 'Contrapunctus I' ten times in succession, Zacher admits to the fact that one interpretation can never reflect all the possibilities that Bach's score and ideas offer. Each version opens a new listening perspective.
 'The entire richness of the musical texture ... must be placed in prominence by the performance instead of being sacrificed to a rigid, immobile monotony, the spurious semblance of unity that ignores the multiplicity it should embody and surmount' (Adorno, 1981, p.145). Bach's compositions can only come out well when the performers are capable of a clear rendition of the multi-layered structure and the complex voicings. Adorno sees the realization of this in the adaptations, transcriptions and instrumentations of Webern and Schönberg. ('What a composition once meant can only be communicated again in a composition; the arranging composer is then the true interpreter of the classic work, his most faithful 'medium', and his instrument of analysis', Hans Rudolf Zeller writes (Metzger, 1980, p.90). Accurate analysis and a new design at the same time; a space between tradition and innovation.) Unsuspected aspects of the work can be revealed in precisely these adaptations; this is how the work is paid tribute. 'Justice is done Bach not through musicological usurpation but solely through the most advanced composition which in turn converges with the level of Bach's continually unfolding work ... his heritage has passed on to composition, which is loyal to him in being disloyal; it calls his music by name in producing it anew' (Adorno, 1981, p.146). Thus ends Adorno's essay. Ends? It actually seems more to appeal to a new opening. It calls for action, creativity. Bach's work is not a finished product, nor is it the conclusion of a creative process; on the contrary, it is an impulse for creativity.
Let's look at that fascinating parenthese, 'loyal to him in being disloyal'. Adorno does not ask us to forget about history (Bach). Nor does he ask us to revise Bach's work by adding or deleting notes. That is not what disloyalty is about. Conversely, loyalty is not about representing his work as authentically as possible either. That would mean to betray the work in which Bach expressed himself because it is open to various interpretations by definition. Music is not a transparent or formal system that banishes ambiguity to be a pure expression of the composer's intentions. To pay tribute to Bach's work means to read his works while bearing in mind the musical accomplishment of our own time. Bach's musical ideas still have power of expression because they were capable of developing; that is to say, they have receded from him in a certain sense. It is precisely by exposing perspectives of his work that Bach could not expose, that we remain loyal to his musical heritage. And disloyal at the same time. Loyalty and disloyalty are interrelated.
Is this Adorno? Or is it my 'Derridean reading' of him? 'Inheritance is never a given, it is always a task', Derrida writes in Specters of Marx. This probably more refers to a position one takes than to the work that such a position presupposes, prefigures, or calls for. The fact that we are heirs does not mean that we own or receive Bach or Bach's work. In order for this inheritance to become meaningful to us, we need to find out what it still holds for us in our current time. Inheritance asks for an active participation and for a necessary transformation. 'This inheritance must be reaffirmed by transforming it as radically as will be necessary. Such a reaffirmation would be both faithful to something that resonates in Bach's [Derrida writes Marx's] appeal ... and in conformity with the concept of inheritance in general' (Specters, p.54). First, it is implicit in the spirit of Bach's work that it can be transformed. Second, interpreting Bach automatically means transforming, selecting, filtering: iterability unavoidably leads to transformation. But this is paraphrasing Derrida. What about Adorno? Could we say that aesthetical arguments led him to ideas that bear some resemblance to Derrida's?
 It should be clear by now why Zacher dedicated Die Kunst einer Fuge to Adorno. Like Adorno's essay, Zacher's project reacts (explicitly or not) against the wave of historization that prescribed the exegesis of Bach's oeuvre throughout the 1950's and 1960's. (Undoubtedly, both entertain a political component next to the aesthetic argument. Adorno makes a connection between notions on performing old music and reactionist ideology. Zacher opposes his conservative colleagues that scorn him. cf. Of the Critics .) Like Adorno, Zacher turns against the idea that an authentic performance praxis would adequately correspond with the inherent sense or meaning of a work. Both refrain from objectifying the past as past. Both can only see justice done to the past through a contemporary actualization. In Zacher's work, this is expressed in a number of different versions in which 'Contrapunctus I' adopts many kinds of musical ideas from fairly recent past.
There is, however, also a difference. Adorno's thinking is still about interpretations, about ways to make contemporary sense of an older text. Zacher does not really seem to practice interpretation (cf. Of Interpretation) . It is not (only) the appropriation of past art into a new context. Bach's text opens perspectives to Zacher from which counter-readings become not just possible, but plausible. His project deconstructs 'Contrapunctus I'. When deconstruction is practiced, it establishes the place(s) of difference already inscribed in the text. Die Kunst einer Fuge reveals unnoticed aspects in the conventional readings of 'Contrapunctus I'. It may give rise to a range of shiftings and replacements that are, in principle, inconclusive. Due to the various changes of perspective, destructive and constructive aspects are at work at the same time. I would call the nine versions after 'Quatuor' encounters or invitations, rather than interpretations.