The use of chance in music written during the last ten years has been much discussed. Expressions like ‘indeterminate music’, ‘aleatoric processes’ are thrown about with little attempt at definition. The situation badly needs clarifying: at least two distinct ideas which involve chance have been used.

Firstly, chance operations have been used to compose—e.g. in John Cage’s ‘Music of Changes’ for piano. Secondly, after a piece has been written down, some aspects of performance are left unspecified—e.g. Boulez’ 3rd piano sonata; Stockhausen’s Piano piece XI. (Thirdly, in some of Cage’s music, both these things happen.)

To understand why Cage uses chance operations to compose, one needs to know what he believes about things in general. His book Silence, a collection of lectures and essays, includes a number of observations about sound, music and the world, Zen philosophy and stories, and personal anecdotes told in a style which recalls Gertrude Stein. From all this emerges a picture of a philosophy of non-involvement which is at least consistent in a bizarre way.

He is fond of the son of mental juggling with paradox which can be extracted from discussion of chance, accident and their role in the world: phrases which have the superficial appearance of being significant and thought-provoking, such as ‘Chance is a leap out of one’s own reach’, occur often. He seems to accept things as they are. He looks with a sort of wonder on things just because they exist or happen; his attitude to the world is one of perpetual, child-like amazement; he seems content to observe things, without any desire to change or influence them. Here is one of his anecdotes. He tells how, after a concert, he said to a composer whose piece he had heard:

‘“Well, I enjoyed the music, but I didn’t agree with that programme note about there being too much pain in the world.” He said “What, don’t you think there’s enough?” I said “I think there’s just the right amount.”’

This acceptance of things as they are gives a clue to his music. ‘Tones must be allowed to be tones,’ he says. He believes we should listen to sounds for what they are, and not as parts of a musical structure which serves the imagination or ideas of a composer. He wants ‘a music free from the writer’s memory and imagination’, pure sounds to be listened to as self-sufficient phenomena, not as vehicles for a musical idea. This is what leads him to use random methods of composition. He uses various devices to ensure notes are selected by chance—coin-tossing, reference to an ancient Chinese ‘Book of Changes’, filling in imperfections in the paper. Rigorous control ensures that the composer’s preference plays no part, even subconsciously.

Successions of sounds presented in this way, though they may engage the attention for a while, soon become boring. They are like things in nature, to be ‘contemplated’, not understood, since there are no relationships or structures. There is nothing for the mind to follow; one listens with the ear only. ‘Is man in control of nature or is he, as part of it, going along with it? To be perfectly honest with you, let me say I find nature far more interesting than any of man’s control of nature. This does not mean I dislike humanity. . . ’