Formerly, the term 'cassation' was hardly used in music except in the 18th century, with the fairly vague meaning of 'divertimento' - its etymology is much debated. The cassation is often given as a farewell serenade or a piece meant to end a moment of music - in that case, it perhaps comes from the Italian word cassazione. But some would have it that it also derives from the German expression gassatimgehen, with a meaning of a nocturnal loyers' stroll (from the word Gasse: path, alleyway). The word, and the ensuing genre, thereby combine dedication, the notion of sending (the serenade aspect) as well as the idea of evening walk, a surprise offered to cronies of the moment or a solemn occasion. In Cassation, equipment for nudity - a 'serenade kit' - is equivalent to paraphernalia for adapting to the darkness. The musicians of the trio most often play 'quasi chitarra' (with or without plectrum and most often con legno), using the bow only for the final minutes of music. The piano part seems to be work in progress (even though the music continues). The clarinet often makes this reparation gesture, chasing away with a blank breath impurities that might compromise the melody - even though the melody, lying in wait, is in fact a long time coming. A haptic crossing, in which the advance is most often made in a groping manner. In this serenade-toccata where verification by touch is simultaneous with the throw, I wanted to evoke tactile vivacity as the supreme art of perception as Diderot described it in Mélanie de Salignac (the most beautiful 'blind woman of the Enlightenment') in his Addition à la Lettre aux aveugles. Auditory, non-surtitled Braille. The instrumental gesture, resting on its own voids, reconstructs an energy by seeking its balance through speed, or in the imprint of a sound revoked by the gesture itself - what Simon Hantaï called 'qualifying mutilation'. However, this breathless race must, beyond the show jumping, preserve the nature of its original genre, the divertimento, even if it verges here, often furioso, on the serenade-pursuit by scratches, iterations, obliterations, and a return of the Gesture that will seek the consequence in its reverse. No reminiscence here, but what might be called the referent will have a refitting (a preliminary title of the work was Wrack - 'wreck' in German). However, it so happens that certain elements of the material of Cassation cross the lovely chord-theme written by Wagner at the time of Tristan then revised in Palermo thirty years later. It is a fragment of a few bars, the last music to be written down by him, a motionless serenade offered to Cosima in the winter of 1882 (and used by Visconti during the closing credits of his film Ludwig).Gérard Pesson,translated by John Tyler Tuttle