(musTh 212) Lecture Notes: Chance Music

Chance music runs contrary to the prevailing 20th-century tendency towards greater and greater control over musical materials.

There are many words that are mostly interchangeable to refer to chance: indeterminacy, aleatory, and improvisation are the most used. I will mostly used indeterminacy.

There are three ways that music can be indeterminant:

• Indeterminacy with regards to composition
• Indeterminacy with regards to performance
• Indeterminacy with regards to both composition and performance

Indeterminacy can be applied to any musical element: tempo, instrumentation, number of performers, pitch, rhythm, articulation, timbre, texture, etc.

Indeterminacy with Regards to Performance

Indeterminacy with regards to performance can affect large-scale form or local events and musical gestures. Large-scale formal indeterminacy usually involves the ability to play individual sections in a changeable order. This is sometimes called mobile form. Using indeterminacy to create local events and gestures usually involves the use of graphic notation, or other purposefully ambiguous and non-standard notational systems.

John Cage

John Cage is the composer most associated with chance music. For him, chance was a deeply philosophical issue, based largely on two beliefs:

• All sounds are musical. There is no musical difference between the sound coming from a piano and the sound of a truck driving by on the street.
• Zen. Chance was a way for Cage to try to remove his ego from the composition process.

In the context of all sounds being musical, one important element for Cage was to define, ahead of a performance, the length of time that the performance would last. You could say that he needed to frame, or define the time span for his composition as separate from the musical sounds going on all the time.

Also important to Cage is the relationship between sound and silence. Although Cage didn’t believe in absolute silence (there really isn’t such a thing), he did still use the term to relate to inactivity. Sound and silence are like yin and yang to him. One needs the other to exist, and together they form balance.