A few years ago, the comedy-rock band Axis of Awesome pointed out a great truth — that every pop song ever written uses the same four chords in the same order.
The fact that it’s not really true makes it no less impressive. I mean, every single song!
Enjoy a couple minutes of this, then we’ll talk.
So maybe it’s not every song, but it is a helluva lot of songs using the exact same progression somewhere in it. The video puts them all in E major, which makes the progression
E – B – c# – A
Putting all of the songs in the same key is not cheating — it’s still the same progression, just like “Happy Birthday” is the same festering turd of a tune no matter what note you start on. Likewise, this is the same chord progression no matter what chord you start on. If you’re in C, it’s C-G-a-F. If you’re in A, it’s A-E-f#-D. But it all boils down to this:
I – V – vi – IV
So why are songwriters addicted to I-V-vi-IV? Because for a basic progression, it’s actually pretty effective. Not a thing of genius, just a really solid workhorse. It’s been robbed of its sparkle by overuse, but it’s worth taking apart to see why it has become such a go-to.
It starts with I, the tonic, because most of the music you’ve heard, like most of the stories you’ve heard, starts at home. The question is where we go next. That’s easy:
As I said in The Hidden Grammar of Music, the most common place for any chord to go is up or down a fifth, and the tonic chord is no exception. In this progression, the I chord goes to the chord it is most closely related to, the dominant, the neon arrow: V.
Now the obvious thing for V to do is spring right back to I. Happens all the time:
The aforementioned “Happy Birthday” does exactly that. But a good chord progression (like a good sentence, story, meal, relationship) should include a little of the unexpected. Since we just did an obvious thing (I-V), we should do something less obvious next. So instead of going back to I, we go to
Remember the deceptive cadence I introduced in the post about Cohen’s Hallelujah? That’s the idea. Instead of going home to I as it was born to do, V can go to vi, the relative minor. It’s interesting — a wee bit of shadow falls across the progression. And as the Hidden Grammar post pointed out,
Only one chord to go. But which one? We could repeat I, V, or vi, but that’d be boring. We want something new to round out the phrase. There are four other chords in the key. Which would be the most satisfying?
Here’s a thought: Each of the chords we’ve heard so far is made up of three pitches from the seven-note scale. When you rack up the pitches in those chords, we’ve heard six of the seven pitches:
You don’t know it, but your ear is thirsty for that missing fourth note. In the key of E, that’s an A. The chord built on that pitch is A major, or (ta-da!)…
All together, then:
As a bonus, when you repeat the progression, IV goes back home to I in a very satisfying and common progression called the plagal or “Amen” cadence.
None of this makes the I-V-vi-IV progression inevitable, but it does make it sensible as a recurring thing, like subject-verb-adjective-object in written language.
Nutshell: If you start in the most common starting place, make the most common harmonic move, follow it with something just a little different, then fill in the one remaining gap in the scale, you get the most common pop progression on Earth.