All The Things You Are | Analysis

The perfect 4th gained its name in the Middle Ages, having been regarded as a perfect consonance (harmonious/pleasing to the ear).

This did not last however, as during the Common Practice Period (1600-1900), it became regarded more as a dissonance that needed to be resolved, either to the major, or minor 3rd. 

Towards and after the 20th century, no longer looked upon as a dissonant interval, it became a building block of harmonic structures in its own right, from the tonal ambiguity of Debussy, to the Jazz of Bill Evans.

This video looks at various melodies that use the perfect 4th as a starting note – as well as an in-depth analysis of “All the Things You Are” which uses the perfect 4th in structural ways, both melodically and harmonically.