FOR MY AESTHETICS, THERE ARE VERY RELEVANT INFLUENCES. 
Artists present their paintings (observed on a flea-market in Ann Arbor, Michigan), that were painted or constructed multidimensionally: people are situated in front of their surroundings, dependent on, but in a way also dominating, the scene. The ambivalence of being involved and, on the other hand controlling, the situation - there are similar aspects in my work. I also compose multilayered pieces that can be perceived in various ways - emotionally or cognitively. My music can be interpreted in different directions. That is the reason why composers such as Gesualdo, Purcell, C.P.E. Bach, Schubert, the later Liszt, Skryabin, Satie, Cage, and Nono, the Russian film pioneer Eisenstein with his dynamic montage-technique, the painters Hiëronymus Bosch, Lichtenstein, Rauschenberg, and Warhol, and poets or philosophers like Shakespeare, Balzac, W. Blake, Mayakovsky, Eco, and Foucault became very important for my way of composing music.
[In: "Angefügt, nahtlos, ans Heute." (1991)]

FLUXUS
Fluxus, with its happenings, actions and descriptions of these, was quite an important movement for me. Nitsch from Vienna, for example, took a bath in the blood of ritually murdered animals. Or musical performances by John Cage (theater pieces, etc.) and Giuseppe Chiari, who wrote very reduced music, which I played in organ concerts for several years. It was not their anti-bourgeois attitude I was most interested in. It was more their way of making bizarre things, combined with a kind of positive provocation. 
[In: '... rote Fäden ...' Conversation with Johannes Bultmann (1994)]

MUSIC OF THE PAST
Music from the past centuries has always been a part of my life. I have never been interested in pop songs. My first experiences were with ancient music and that is the reason why I have a special interest in the music of J.S. Bach or Schubert. In the run of my musical studies, I began to interpret music history in the way of dialectic materialism. For me, the history of music consists not only of a number of works existing in different centuries being analyzed in a more anecdotal way (in this way music is taught in school or even in university). I was more interested in contextualizing musical works with their social and historical contexts, finding philosophical expressions in musical works in order to explore "guidelines" of music history. Guidelines that develop in secret, and then enter the mainstream, like the development of certain forms of autonomous instrumental music. Or connected with the upcoming bourgeoisie - the beginning of major-minor tonality. It's which differentiation evolved analogous to functional separation within music and the development of virtuosity. 
[In: '... rote Fäden ...' Gespräch mit Johannes Bultmann (1994)]

CROSS-CONNECTIONS
The use of interdisciplinary techniques is important for many of my works, for example, the structure of my work Wirbelsäulenflöte is based on the operaKing Arthur by Purcell. Schubert's first song Gute Nacht in his Winterreise is used in ... fürs Vaterland, as an expression of times of political and social oppression, and times marked by the danger of war. Apart from these two examples, I incorporated Liszt's pure thirds in my acronym Den Müllfahrern von San Francisco in order to disconnect them from their strange religious and social meaning in Liszt's œuvre. In the '70s, I became acquainted with Satie, and from that time on, I have often used aspects of his - and Cage's - aesthetics to emphasize my ideas. All of these references to other composers are used in certain compositional projects and are dependent on my personal situation - which means the direct present.
[In: '... rote Fäden ...' Conversation with Johannes Bultmann (1994)] 

LUIGI NONO/EDGAR VARÈSE
Nono's composing techniques - montages, hints, citations from past composers or poets, the dialectic between compositional liberty and severity, the flexibility of fracture - all of these points do not have a worn-out effect, although they are all influenced by Nono's classical education or his old (Venetian) origins. Nono's ideas are often based upon Greek mythology and on dealing with fundamental questions, and are influenced by foreign cultures as well. He shows that there are other conditions in the world besides a rich European culture, and that it is not enough to develop new ideas with radical thoughts or fashion-like techniques only concerned with the surface of phenomena. It is more important to attack fixed social structures - structures that determine our thoughts and actions in a way that makes us think that not being authentic is the most normal thing in the world. Nono and Varèse - who called sound son organisé - thought sounds were like organisms, and they used space to separate interpreters from each other in the concert hall. At the same time, Nono would create new sound dimensions by electronic procedures. Although Varèse put his emphasis on separated, independent layers of sounds, these created very distinguished relations with each other. Nono worked more integrally; he dealt with the material in the tradition of the Second Viennese School and thereby, he creates an historical aura. Apart from many stylistic differences, there is one fundamental aspect Nono and Varèse have in common… maybe led by rational thought, I was very attracted by their clear constructions combined with an openness of form. 
[In: ...yes, No-no... (1997)]

JOHN CAGE
John Cage's approach pushes towards fantasy and tries to attack antiquated traditions in music. Musicians/interpreters should develop their own responsibilities in order to test anarchical mechanisms in conceptions of arrangements of his experiments (H.K. Metzger). The composer's influence is minimized in order to reach a maximum of freedom on the interpreter's side. Doubts are thus advisable. In his late works, Cage retracted his "intention-less" approach and went back to his harmonic ways of composing from the '40s. If this is admitted, his procedure has to be accepted. The mark "espressivo" that Cage used in his 103 for orchestra is meant as advice to the interpreters; they should be responsible for their sounds. Whether this implies a greater freedom than the meaning of espressivo in traditional chamber music is hard to tell. Well, this is a little step towards freedom in music that does not question the whole system. In many compositions and concepts, Cage dealt with the meaning of now, with the most famous example being 4'33". Here, he confirmed the First World tendency of settling down, where everyone can stay home, being surrounded by his own music. Listening to music is as useless as composing music. In a way, Cage confesses himself to an epoch characterized by Paul Virilio as an epoch of "simulation". Shocking effects once provoking pieces were reduced; Cage did not deal with musical material in a progressive way any longer. In a way, dreams or utopias became stunted, but that does not mean that the aesthetic of the '50s onwards does not offer opportunities to use flexibility and openness in meaningful ways. 
[In: Nicht Traum. Traum: (1999)]