Tatsachen in zwei Sätzen is the first piece equipped with an opus number. The reason for this is that, from this point on, the works reached a quality that met my demands. Nearly all prior scores have fallen prey to voracious destruction or have been lost. Exempt from this are some of the electroacoustic music as well as some of the sound installations I have created prior to Tatsachen in zwei Sätzen. The initial idea was to develop a polyphonic piece. In order to do so, the violinst plays on or, respectively, behind the bridge. At the same time, he slides on all four strings with the left hand, hits and depresses strings, hits and instantly mutes strings or plucks strings. Additionally, the violinst makes use of both hands in order to hit the body of the violin. Before the second movement starts, a kind of intermezzo takes place. As in the first section, the player plucks and hits the strings with the left hand. Additionally, the same hand is used to mute the strings, while the right hand dabs the strings on fingerboard positions, either with the wood or screw of the bow. The first movement, including the intermezzo, is quiet and subtle. It is opposed by the second movement, which is loud and violent. Harmonic glissandi, highest possible bow pressure, fingering between fingerboard and bridge/behind the bridge are some of the techniques that are articulated strongly. They contribute to the squeaking and whistling sound-wise character. The piece ends with a low density and diverse distribution of the articulations. They refer to all prior sections. The piece was revised once the development of a notation system for unconventional extended playing techniques had been finished. The revision was extensive, but mainly concerned with the methods of notation, not the content of the piece.