Karlheinz Essl

The Chances of Chance

Some Remarks on Artistic Practices based on Chance and Collaboration

Keynote for the 7th Conference of the European Research Network Sociology of the Arts:

Sep 6th, 2012
University of Music and Performing Arts in Vienna


In this keynote, I will analyse my own creative process as a composer. Instead of postulating a theory I take the freedom to look back on my artistic development. Starting as a classically trained composer in the 1980ies, a radical change occurred as I got involved with computer technology. This altered my approach to musical composition and brought me in contact to scientific theories such as chaos research, networks and algorithms. This also influenced my working method as a composer: Before, I was mainly writing instrumental scores in splendid isolation, trapped in a self-imposed ivory tower. But then I realised the necessity for exchanging my ideas and artistic research with others in order to learn and to broaden my horizon.

The rise of the Internet in the early 1990ies enabled me to get in contact with a world-wide community of composers who use computers for artistic purposes. At this time, the Net was not yet commercialised, but rather mainly populated by individuals who were eager to share their knowledge and personal achievements. While working on my realtime composition Lexikon-Sonate for computer-controlled piano I started to develop an open source software library for algorithmic composition called RTC-lib. Instead of a score, the infinite Lexikon-Sonate was distributed as a computer program on the Internet, and is currently running on thousands of computers all over the world, generating music that never ever repeats itself.

This all has changed my life as a composer from a lonely hermit to a person who is embedded in a constantly changing global network. This also brought me into contact with improvisation which has in turn required the development of my own electronic instruments for live performances. Furthermore, I have learned about the advantage of chance which acts as a splendid source for innovations and new artistic expressions.

Within my presentation, I will also play two performances of works that are based on self-developed computer programs utilising random operations and user interaction. This dialectic of order and chaos results in a paradoxical situation which enables me to improvise with myself, bridging the gap between composition and improvisation.


Handbook Of Research On Creativity, ed. by Kerry Thomas and Janet Chan, Edward Elgar Publishing (Cheltenham 2013), p. 297-307. - ISBN: 978 0 85793 980 7


At a congress about Artistic Practices, I will speak about artistic practices. I am emphasizing the word "practices" as I am an artist and not a theorist. What I present today is not a theory about my artistic pratice which is mainly situated in the field of musical composition. Rather, I want to share some insights into my creative process which is strongly influenced by my preoccupation with chance and the collaboration with other individuals. Such challenges forced me to open myself to powers that I cannot entirely control. They have become important sources of inspiration and changed the course of my development from being an „ivory tower“ composer into being an artist who has finally learned how to interact and cooperate with others in a creative way. Furthermore, this transformation process has also changed my understanding of artistic creation.

In my keynote, I will investigate the role of chance and collaboration in selected artistic projects, demonstrating it with two performances. Furthermore, I will relate certain practices with cooking as a comprehensive metaphor for a specific artistic approach that reconciles life and art. This approach is indebted not at least to the fascinating cosmos of an artist whose 100th birthday was celebrated yesterday: John Cage.


What is chance? There are many answers to this question, using different terms. Complex situations that we can't understand are often considered as unpredictable even though they are not random at all. Unrelated events that happen at the same time are described as coincidences; they might result in lucky strikes but also in catastrophes. In modern physics, Newton's mechanistic world view has been replaced by probability theory which supplies a much better understanding of complexity. Information theory uses the term entropy as a measurement of order vs. chaos. This development has definitely had an impact on our modern conception of reality. The understanding of our environment is no longer thought of being just a simple deduction from a static object, but rather as a reconstruction formed by the perception of the individual observer.

Chance can become a strong motor for innovation as it opens new and unknown possibilities. The discovery of Penicillin happened by chance as serendipity when a bacteria culture was contaminated by a fungus. However, it needed an alert person like Alexander Fleming who drew the right conclusion. Chance might open a door, but it also requires someone to walk through it.

Soon after World War II, young composers from Europe like Karlheinz Stockhausen, Luigi Nono and Pierre Boulez took a radical step. By proclaiming a "tabula rasa" (Stockhausen 1953), they tried to get rid of any musical tradition which had become suspicious due to the cultural destruction of the Nazis. The attempt to construct music scientifically by a completely determined control of its "parameters" paradoxically created results that appeared not ordered, but random. In this situation, John Cage appeared at the Darmstadt Summer Courses with his own concept of chance (Cage 1961): Although his piano work Music of Changes (1951) was composed with chance operations drawn from the Chinese oracle book I Ching, it sounded similar to those pieces composed by his Serial colleagues which employed deterministic methods. This had an enormous impact: it demonstrated that order and chance are no longer hostile antagonists; but rather, they can be regarded as complimentary relations that form a gradual transition between determinacy and indeterminacy. In this way, random and order can be viewed as extreme positions of the same thing, resolving the contradictions between them.

This fostered the understanding that chance does not only relate to chaos, but that it could also be utilised for creating order (Koenig 1965). Interesting enough, this concept was later adopted in system theory like Ilya Prigogine's influential Order out of Chaos (Prigogine 1984).

When this book came out in the 1980s, I was studying composition in Vienna, eager to absorb new theories and broaden my horizons. Studying the music and writings of the aforementioned Serial composers and John Cage I became more and more interested in non-traditional concepts of musical composition. From this time on I started to use computers to develop software for musical composition, combining deterministic and non-deterministic strategies.

The use of chance operation doesn't liberate the composer from his artistic responsibility. It should be used with care and never become a belief system or a substitution for meaning. Yet, chance has provided an amazing supply for inspiration and innovation in my work as it builds a bridge between concepts of the natural sciences and artistic ideas. In my own understanding, art reflects and transforms processes at the foundation of everything living.


When I was working on my musicological thesis about the compositional thinking of Anton Webern (Essl 1991), I first came across this concept. Webern was referring to the idea of Goethe's primordial plant which he related to his own compositional practice.

The primordial plant does not exist in nature. It is an abstract model that Goethe conceived while visiting the botanic gardens in Palermo. In a letter to his friend Johann Gottfried Herder he wrote:

„The primordial plant would be the most wonderful creation of the world, for which nature itself should envy me. With this model and the key that it contains, one could invent an infinite number of plants, ones that despite their imaginary existence could possibly be real, thus which are not solely literary and painterly shadows and illusions, but which possess an inner truth and necessity. This same principle would be applicable to every other aspect of life as well.“ (Goethe 1787)

In Goethe’s primordial plant, the variations of its structural components (like branches, stems, leaves, flowers, roots) create an endless variety of plants, even some that do not exist in nature. Like Webern, I understood that this principle could also be fruitful for musical composition. Drawing an analogy to biology and Darwin's theory of evolution: the development of species is governed by mutations which are mostly caused by chance. And this is also the case in my music, as I will show later on.

These ideas radically changed my compositional thinking. In contrast to the fixed works that I had been composing so far I discovered a fascinating alternative: by transforming a compositional idea into a more generalized abstract model I could use this "formula" for obtaining an infinite number of structural variants of the same piece. In so doing, the traditional concept of a deterministic and untouchable work (an „opus magnum et perfectum“) is transformed into a fluid and open process which can by expressed by an algorithm.

The 'Algorithmic Revolution' (Weibel 2005) in the arts started in the 1950s. It has drastically changed not only the way in which art is produced, but also the function and self-conception of its creators. With the help of algorithms, the composer is no longer a demiurge who controls every tiny detail of a composition through the power of his imagination. By utilising algorithmic methods such as automatisms, random operations, rule-based systems and autopoietic strategies, some artistic decisions are partly delegated to an external instance. This might be regarded as a weakness of the subjective autonomy. On the other hand, it enables one to gain new dimensions that expand investigation beyond a limited personal horizon. From this basis, algorithms can also be regarded as a powerful means to extend our experience – they might even develop into something that may be conceived as an 'inspiration machine'. (Essl 2007)

When I undertook this crucial change 20 years ago I was working at IRCAM in Paris, a research center for computer music which was founded by Pierre Boulez. While composing a piece commissioned by this institution I came in contact with a new programming language called Max (Puckette 1988), conceived for the creation and manipulation of realtime processes such as sound and music.

In order to experiment with the idea of Goethe’s primordial plant, I developed software modules for algorithmic composition called Realtime Composition Library for Max (Essl 1992b). Using this software, I created a series of so-called structure generators (Essl 1996) that can automatically compose a broad palette of piano music. The parameters of these generators were mostly controlled by specially designed random operators in order to achieve a never-ending and never-repeating stream of notes. These „notes“ (or better: playing instructions which define the key strokes on the piano keyboard) were played in realtime on a computerized player piano – without the need of a pianist.


My experiments took place in the silence and darkness of IRCAM’s underground studios. Sometimes I was visited by Isabel Mundry – a composer friend of mine – with whom I discussed my findings. But most of the time I was working alone in splendid isolation – a common practice for me so far.

At this time, in 1993, the World-Wide Web as we know it today began to emerge. Thanks to this development it became easy to connect with other researchers and composers all over the globe who worked on similar or related ideas. How wonderful to discuss and share my findings, and to get an immediate response! Finally, I decided to uploaded my Realtime Composition software as an open-source package so that others could use and modify it. This brought me in contact with highly interesting people who were using my software and helped me to improve it. Our communication was based on e-mails and mailing lists – and in this way, a network of dedicated people soon emerged.

By coincidence, at this time I was contacted by a group of media artists and researchers called „Libraries of the Mind“. They were implementing Andreas Okopenko's Lexikon-Roman – the first hypertext ever written in literature – in the form of an electronic book which could be read on a computer.

The original novel published in 1970 (Okopenko 1970) consists of several hundred small chapters. By reference arrows (as in an encyclopedia) the readers could make their own investigations through the multiple nested web structure of the text. Instead of presenting a sequential text with a linear reading direction, Okopenko provided a structure of possibilities, which challenges the readers to become creators of an individual version of his novel. Okopenko, who was also part of this group, demanded the inclusion of additional media like illustrations, photos, and music into the electronic version. And I was asked to compose the music for it.

After reading the book I realized that the suggested procedure to compose "jingles" for each keyword would be counterproductive. This music cannot merely consists of snippets which are replayed whenever a certain chapter has been selected. Unlike a picture or a text, music is always related to time. It takes place within a given period of time, whereas beholding a picture or reading a text is not subordinated to a certain time span. One can meditate over a text for a long time, or quickly read over it. So it became clear that the music for this piece should reflect the reading behavior of the reader: if she spends a long time on a chapter, the music should stay in the same "mood" or character, whereas zapping between the textural links would result in quicker changes of the music. The ideal solution, however, would be a pianist who improvises on a piano, altering his playing whenever a new keyword was chosen. As this was practically impossible to achieve, I decided to simulate the pianist by a computer program which acts simultaneously as a composer and an interpreter.

The result was a work-in-progress for computer-controlled piano called Lexikon-Sonate (Essl 2000): a composition which is not represented by musical notation but by a computer program that composes and performs the piece – or, better: an excerpt of a virtually infinite composition – in real time. It is currently still distributed on the Web as freeware and is living on thousands of computers around the globe, serving as an inexhaustible source of musical surprises.

Now I would like to show you a short demonstration of my piece. Originally, it only existed as a hermetic computer program which only reacted to the changes of keywords. Later on, I opened the closed structure of the software in order to access its underlying algorithms by external devices such as MIDI controllers, pedals or keystrokes on the computer. This has transformed the piece into an instrument which allows me to perform and improvise the Lexikon-Sonate without even touching a single key on the piano. By listening to the generated music and immediately reacting to it, a powerful interaction with the computer takes place.

Lexikon-Sonate (1992 ff.) performed by the composer on a Yamaha Disklavier
12 Jul 12 2016, NIME Conference 2016 (Brisbane, Australia)


As a composer, I was mainly concerned with writing scores which required an interpretation by musicians. Lexikon-Sonate does not need musicians at all, as its software realises the composition and the performing part by itself. Still, I am highly interested in collaborations with others. In order to foster this interest, I had to leave my „throne“ as a composer who tends to control everything and utilize instrumentalists for his own purposes. Instead of commanding musicians in what to play I began designing my own electronic instrument m@ze°2 (1998 ff.) which I use in solo performances and free improvisations with others. It is based on a computer program written in MaxMSP and consists of a variety of structure generators which are not generating piano music, but electronic sounds. This instrument is controlled by external devices such as MIDI controllers, pedals and a web cam and allows the creation of electronic music on the fly.

User interface of m@ze°2

User interface of the m@ze°2 realtime composition environment (1999-2012)
© 2012 by Karlheinz Essl

Free improvisation combines the aspects of chance and collaboration, but also of collective composition and interpretation. The idea of music that emerges in realtime (like Lexikon-Sonate) is now transformed into a dialogue between equal partners where nobody knows in advance exactly what's going to happen (Essl & Hauser 2004). The music which is created collectively is the result of a complex communication process which happens strictly "in time". Although nothing is planned in advance, the audible result will not appear arbitrary if the improvisers are able to connect with each other by sacrificing their ego in favor of a common sound world that they are creating together, in the moment.

OUT OF THE BLUE: Agnes Heginger (voice), Karlheinz Essl (electronics)
Free improvisation on a poem by August Walla
24 Jun 2012, Art/Brut Center Gugging

Many years of improvisations with splendid soloists and ensembles have left traces on my compositional approach. Thanks to these experiences I have been able to open myself to the uncontrollable and to accept the unknown. Chance became an intimate friend of mine.

In 2008, I started a composition project called Sequitur which embraces 14 different pieces for various solo instruments (such as flute, cello, toy piano, trombone or electric guitar) with live-electronics. The idea was to confront a musician who plays from a score with electronic sounds that are exclusively generated from the live input of the instrument. Using an algorithm based on chance operations, the result is not completely predictable. Thanks to this, each performance is different, stimulating the musician to listen carefully to the electronics and react accordingly.

Isabel Ettenauer performing Sequitur V
11 Mar 2009, Klosterneuburg, Essl Museum (A)

Alongside these 14 compositions, I developed a related environment called non Sequitur which uses a similar software for the live-electronics, but doesn't supply a notated score. Instead, I improvise the piece myself on more exotic instruments like kalimba, music box, or sound sculptures that have been designed specially for my purposes. Due to chance operations used in the software, the electronics behave like an unpredictable musical partner which I can control only to a certain extent. This creates a paradoxical situation wherein I split myself into two parts that are improvising together: one playing the instrument, and the other influencing the electronics. This creates surprising moments which tackle my inspiration as a player, and finally enable me to improvise with myself.

The instrument that I will play today was built by the Austrian sculptor Johann Feilacher for me. Once I visited him in his studio where he showed me a series of large wooden trunks which he had perforated with a chain saw. In my imagination, those raw sculptures could probably sound quite promising if they were only much smaller. Mentioning this to him, he just shrugged. Surprisingly, a few months later he was ringing at my door. In his hands he held an instrument which I later entitled Klangfeile (= sound rasp). This I will now use for my second performance.

Karlheinz Essl performing non Sequitur on a sound sculpture created by Johann Feilacher
Videostill © 2010 by Sylvia Kummer


Let me now illustrate an aspect of my artistic practices with another field of arts: cooking. When preparing a meal you can either follow a recipe or consult your memory. But in order to create something new, you might use different methods. You can go into a store and buy the best ingredients you can find. Or you can imagine unusual combinations of foods and spices. Eventually, you might get inspired by adapting exotic cuisines or by obeying the rule system of a certain diet. Maybe you would become an idea by the absence of certain ingredients. Or you accept what chance is offering you.

Recently, while composing, I became hungry. When I opened the fridge, it was nearly empty. It only contained a carrot, half a broccoli, and leftovers of radicchio. In other words: a root, a flower and leaves, in three different colors and textures. In my head I instantly began to improvise with those randomly supplied ingredients trying to imagine different ways how to process them. For cooking does not exhaust itself in combining of aliments; the preparation and processing of the raw material plays an important role. The leaves of the radicchio were separated, the carrot cut into cubes and the buds removed from the broccoli's stem. Then I decided to leave the radicchio raw and to blanch the carrot and the broccoli parts which I marinated with soy sauce. Finally, I mixed the vegetables together and seasoned them with italian dressing. Honestly, the result was really tasty!

Random Salad created by Karlheinz Essl

© 2012 by Karlheinz Essl

This relates to my compositional practice when I first need to examine my material – whether it is a sampled sound object, an instrument or a certain structural idea. Sometimes those ingredients just come to me – by coincidence or serendipity – and I have to evaluate them. The raw material often needs some sort of processing, a specific preparation, or certain refinements. And then, by relying on my musical intuition and my experience, I start working: maybe with a series of experiments, or by improvising. Meanwhile I constantly analyze the results which helps me to further refine my working strategies.

The cooking metaphor played an important role in my last piece for tuba and live-electronics that will be premiered in a few weeks at the Klangspuren festival in Tyrol. Two years ago I received an e-mail by a tuba player named Karlheinz Siessl who found it funny that our names are so similar: they only differ in the syllable "si". He suggested a collaboration and asked me to write a piece for his instrument. Shortly thereafter I invited him into my studio where we improvised together in order to become acquainted with each other. The result was so enjoyable and promising that I agreed to compose a piece for him.

Pondering over the piece, I suddenly found its title – Si! – which means "yes" in Italian and Spanish. By coincidence, this is also the solmization syllable for the note B, the fundamental tone of the tenor tuba I was using. With those ingredients I started the cooking process similarly as I described above where one decision inevitably leads to another. Observing the syllable "si" from various perspectives I decided to emphasize the positive message of this word. A piece of literature came into my mind where the word "yes" is used in a highly musical way: the very end of James Joyce's novel Ulysses where Molly Bloom babbles her famous soliloquy in a daydream:

and first I put my arms around him
and drew him down to me so he could feel my breasts all perfume
and his heart was going like mad
and yes I said
yes I will

I asked a former student of mine to record these lines in Italian; they secretly serve as an underlying Ariadne's thread throughout the piece. By filtering the sound of the tuba with the spectrum of the female voice (employing a technique called convolution), this instrument is now able to speak in tongues. In order to obtain the desired results it was necessary to transform the sound of the bassy tuba into a range that has more common overtones with the voice. As it was nearly impossible to achieve this with normally blown tuba sounds, I had to invent new playing techniques. So I ended up „mis-using“ the tuba as an exceptional percussion instrument which is caressed and beaten. Furthermore, I also utilise it as a brass tube to breathe and whisper into it, taking advantage of its rich resonances.

I am sure I could never have composed such a piece if I had not risen to the challenges of chance and collaboration upon being unexpectedly approached by a person whose name just sounds similar to the one that I carry.

Karlheinz Siessl (euphonium) and Karlheinz Essl (live-electronics) performing Si!
30 Nov 2015, Innsbruck


Collaboration changes the behavior of the artist to no longer assume the function of a godlike creator who controls everything solely by himself. Particularly in improvisation, the idea of shared authorship has become a powerful substitute for the outmoded concept of a genius who determines every detail of the work, alone and in splendid isolation.

Including the element of chance in the artistic process leaves traces on the artwork itself. It is no longer viewed as an autonomous and untouchable opus magnum et perfectum but as an open process which can manifest itself in a variety of appearances. This, however, changes the way art is perceived. Instead of being forced to decipher a specific message that the composer has put into his work, the listeners are invited to re-construct the artwork by their individual acts of perception (Essl 1992a). Thereby, a highly personal version of the work is invented by each listener who in turn becomes an active participant in the whole creation process.


Cage, J. (1961). ’Indeterminacy’, in: Silence: Lectures and Writings. Middletown, Connecticut: Wesleyan University Press, pp. 35–49

Essl, K. (1991) Das Synthese-Denken bei Anton Webern. Studien zum Musikdenken des späten Webern unter besonderer Berücksichtigung seiner eigenhändigen Analysen von op. 28 und op. 30. (= Wiener Veröffentlichungen zur Musikwissenschaft, vol. 24) Tutzing: Hans Schneider

Essl, K. (1992a) ’Kompositorische Konsequenzen des Radikalen Konstruktivismus’, in: Nauck, G. (ed.) positionen. Beiträge zur Neuen Musik, vol. 11 "Mind behind: Systemtheorien", Berlin-Ost: Verlag positionen, pp. 2-4

Essl, K. (1992b) Real Time Composition Library for Max. Paris: IRCAM.

Essl, K. (1996) Strukturgeneratoren. Algorithmische Musik in Echtzeit. (= Beiträge zur Elektronischen Musik, vol. 5) Graz: IEM

Essl, K. (2000) ’Lexikon-Sonate. An Interactive Realtime Composition for Computer-Controlled Piano’, in: Enders, E. and Stange-Elbe, J. (ed.) Musik im virtuellen Raum. (= Musik und Neue Technologie, vol. 3) Osnabrück: Universitätsverlag Rasch, pp. 311-328

Essl, K. and Hauser, J. (2004) ’Improvisation on Improvisation’, in: Schweiger, D. et al. (ed.) Musik-Wissenschaft an ihren Grenzen. Manfred Angerer zum 50. Geburtstag. Frankfurt am Main: Peter Lang 2004, pp. 507–516

Essl, K. (2007) ’Algorithmic Composition’, in: Collins, E. and d’Escrivan, J. (ed.) The Cambridge Companion to Electronic Music. Cambridge: Cambridge University Press, p. 107

Goethe, J. W. (1982) ’Letter to Herder: 17 May 1787’, in: Trunz, E. (ed.) Italienische Reise (= Hamburger Ausgabe, vol. 11). Munich: C. H. Beck, pp. 323–24

Koenig G. M. (1965) ’Serielle und aleatorische Verfahren in der elektronischen Musik’, in: Electronic Music Reports, vol. 4. Utrecht: Institute for Sonolgy, p. 113

Okopenko, A. (1970) Lexikon-Roman einer sentimentalen Reise zum Exporteurtreffen in Druden. Salzburg: Residenz

Prigogine, I. and Stengers, I. (1984) Order out of Chaos: Man's new dialogue with nature. New York: Bantam Books

Puckette, M. (1988) ’The Patcher’, in: Proceedings of the International Computer Music Conference. San Francisco: International Computer Music Association, pp. 420–429.

Stockhausen, K. (1953) ’Zur Situation des Metiers (Klangkomposition)’, in: Schnebel, D. (ed.) Texte zur elektronischen und instrumentalen Musik, vol. I. Cologne: Du Mont, p. 48

Weibel, P. (2005) ’Die Algorithmische Revolution. Zur Geschichte der interaktiven Kunst’, in: Weibel, P. (ed.), Die Algorithmische Revolution. Karlsruhe: ZKM, pp. 1–5


Karlheinz Essl (Wien), der zweite Hauptredner, ist Komponist und bot eine anschauliche und zugleich reflexive Präsentation seiner künst­lerischen Entwicklung und Kompositionspraxis. Ausgehend von einer Auseinandersetzung mit den Werken von Anton von Webern, der die Offenheit von kompositorischen Prozessen hervorhob, sowie von John Cage, der eine experimentelle Arbeitsweise entwickelte und ein erweitertes Verständnis von Musik schuf, begann Essl in den frühen 1990er­ Jahren neue technologische Möglichkeiten für die Tongenerierung zu nutzen. Dabei gewann der Zufall als künstlerisches Gestaltungselement an Bedeutung und das veränderte in der Folge seine kompositorische Arbeitsweise. Anstatt die musikalische Komposition in einem Notationssystem festzuhalten, entstand eine performative Form des Komponierens, die ihm einen neuen Freiheitsraum eröffnete. Diese Differenz verglich er mit dem Kochen nach einem vorgegebenen Rezept und dem spontanen Kochen, das auf erfahrungsbasierten Kenntnissen über Kochmaterialien, Gewürzen, Kochtechniken u. a. möglich wird. Wenn also die musikalische Komposition innerhalb gewisser Rahmen offen und unvorhersehbar bleibt – man denke auch an die Aleatorik –, dann kann der Kompositionsakt keine absolute Kontrolle über die musi­kalische Aufführung anstreben. Sowohl die Kompositionsarbeit als auch die Aufführung nehmen eine fluide Praxisform an.

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