Jonathan L. Friedmann, Ph.D.
A chord played in isolation is ambiguous. It might be the tonic of one key or a degree of several others. Without additional chords on either side, it cannot establish a definite mood or meaning. Likewise, a string of chords splayed randomly into the air does not have a perceptible purpose. Without pointing in a specific direction or outlining a reasoned path, it is basically functionless. Only when chords occur in a progression do they have a discernible goal, whether establishing a key, modulating, transitioning, or reaffirming.
Not surprisingly, the chord progression is the most universally satisfying—and thus the most ubiquitous—Western harmonic tool. This owes to its fulfillment of two psychological needs: structure (beginning, middle, and end) and the resolution of tension. Logical progressions convey the order and predictability we strive for in life, but often do not achieve. It is no accident that the most common progressions are also the most comforting, such as I-V-vi-IV and “Pachelbel’s Progression” (I-V-vi-iii-IV-I-IV-V).
In contrast, a single chord, no matter the type, has no analogue in actual life. Unlike the chain of cause and effect that drives every natural process, the isolated chord has no antecedents or consequences. It is irrelevant to our interconnected world. As John Muir famously wrote: “When we try to pick out anything by itself, we find it hitched to everything else in the Universe.” A chord without a “hitch” is un-relatable.
An unsystematic succession of chords falls between progression and isolation. Although there is movement from one chord to the next, it lacks the gratifying impact of anticipation, pattern recognition, and closure. This sort of harmonic series hits perhaps too close to home: it resembles the aimless meandering of existence. Instead of affirming a desire for order, it holds a mirror to life’s frequent chaos and seeming randomness. It is relatable in a negative way.
To put it simply, an isolated chord is unreal: it is alien to any physical or psychological process. A chord succession is real: it reflects the unpredictable nature of existence. A chord progression is ideal: it embodies the direction and design we seek.
Visit Jonathan’s website to keep up on his latest endeavors, browse his book and article archives, and listen to sample compositions.