Information and Exformation in Music

In James Gleick's recent book on Information The Information: A History, a Theory, a Flood, he gives us a exhaustive overview of the meaning of Information. But once one has all the information on Information, ultimately what matters is the essence of information that is useful and relevant, sometimes referred to as exformation.

Exformation is a term coined by author Tor Nørretranders in his 1998 book 'The User Illusion', and defined as explicitly discarded information. It is all the extraneous details that are removed to achieve an elegant result--one in which is easy to understand and use. It is everything cut to the chase.

An example of exformation in music is the solo sax player on the corner, improvising over chord changes that are implied by the solo. Harmony is the vertical orientation of scales or melodies being played without accompaniment. What we hear temporally defines the harmonic context, regardless of whether a chord is being played. Skilled improvisers know how to divine harmony from melody by distilling the essence of chords through playing 'landmark' pitches--those most important to outline the harmony.

Counterpoint is also all about exformation: two or more melodies suggesting a vertical orientation, a bass voice in context with a soprano voice.

Two note chords can represent more complex harmonies by leaving most of the notes out. Typically a bass note will define a chord, but it isn't always necessary because it is implied by the other notes around it in the melody.

Here is an example of some of the chords that are implied by two notes, C and E-flat or D-sharp: