Transparency. Does that make sense to anybody? (Crowd cheers) Transparency. (Donald Trump to David Letterman in the Late Show, October 2012.)

There might have been a hundred thousand human beings in Capitol Square, or twice that many. The individuals, like the particles of atomic physics, could not be counted, nor their positions ascertained, nor their behavior predicted. And yet, as a mass, that enormous mass did what it had been expected to do by the organizers of the strike: it gathered, marched in order, sang, filled Capitol Square and all the streets around, stood in its numberlessness restless yet patient in the bright noon listening to the speakers, whose single voices, erratically amplified, clapped and echoed off the sunlit facades of the Senate and the Directorate, rattled and hissed over the continuous, soft, vast murmur of the crowd itself. (Ursula Le Guin, The Dispossessed, 1974.)

You have the right to be obscure, especially to yourself. (Edouard Glissant, Philosophie de la Relation, 2009.)

The problem encompassed by determinacy and indeterminacy is a permanent one in music, both for composition and also for performance. Two performances of the same work are never exactly the same. They hover around what we may consider an ideal mean of performance, dependent upon errors and the style of the performer. This is understandable. 

[Is this the end of the West as we know it?
It’s the end of the West as we know it.] (Anne Applebaum in The Washington Post, March 2016 ; Carl Bildt in The Washington Post, November 2016.)

Determinacy constitutes a very important and deep question, especially when considered against a background of physics and computer science. We know that since the time of Copernicus and Kepler the movements of the planets and other celestial bodies have been geometrically defined. With Newton, gravitational theory seemed to be so accurate that repetitions of planetary motion could be foreseen and predicted until the end of time. 

This is like saying that you have a score, you memorise it, and then all you have to do is play it. Theories about the movements of the planets, however, make an abstraction of the influences of other celestial bodies – even remote galaxies – as a result of which the predicted movements are not exactly in conformity with theory. Actually the movements in the far future cannot be foreseen with accuracy – the seemingly predictable movements are in fact unpredictable. 

The whole field of science dealing with such phenomena is today known as ‘chaos’, and the laws which govern the variations of behaviour are caused by ‘strange attractors’, a term used in contemporary physics.

[I am pride. The proud root of all evil.
I am Superbia, the first of the seven capital sins. I am always the first.
The tree of wickedness grows out of me. My six daughters are its forbidden fruit: 
gluttony - indolence - avarice - wrath - envy - lust. 
But see for yourself how Luciphera Superbia, her coach, drawn by the six minor sins, 
drives in triumph to her wedding with the world, accompanied by her retinue and by Blasphemia, her maid] (Text excerpt from Superbia by Ulrike Ottinger, 1986.)

In performing a score or something from memory we come across surprisingly similar problems. We never hear the same performance. 

This fact perhaps makes the performing of traditional music interesting, because each time the skilled performer brings with him something unforeseen and interesting aesthetically. It is also a matter of interest to see how the problem of the unforeseeable – of surprise – was anticipated at the compositional level; how determinism was treated during the writing of a piece and to what extent it constituted an integral part of the composition. (…)

[The sun's coming out.
Your son's coming out.] (Kate Bush, Cloudbusting, 1985. Soundtrack of Burger und Ther by Mark Ther. )

A composer working in the domain of rhythmic music faces this problem of expectancy in rhythm. Through the history of the development of rhythm there has been a tendency for increasing complexity based on the degree of unexpectedness of what might follow any musical event; therefore this is an approach based upon a non-deterministic way of thinking. (Iannis Xenakis, Determinacy and indeterminacy, Organised Sound, 1996)

The scattered disc is still not understood well. Astronomers believe that it was created when objects in the Kuiper belt were "scattered" by the gravity of the outer planets, mainly Neptune. Unlike most objects in the Solar System, which move in a round and flat path, scattered disc objects go every which way. (“Scattered Disc”, Simple English Wikipedia.)

Commisaire d'exposition : Barbara Sirieix 

Artistes : Ericka Beckman, Laetitia Badaut Haussmann, Anetta Mona Chisa & Lucia Tkáčová, Pauline Curnier Jardin, Feminist Land Art Retreat, Ulrike Ottinger, Richard Sides, Jay Tan, Mark Ther, Julien Tiberi, Lenka Vítková, Angharad Williams